Rokinon/Samyang 135mm discussion

[uneven compass]

He's already in

Always looking for new cult members

[wicked beacon]

I'm one of you guys. x)

[bold acorn]

What's a dovetail

[thorny jetty]

I need to whoop your ass

The metal plate that mounts dovetail rings or a optical tube onto a mounthead

[bold acorn]

What's a dovetail ring

[bold acorn]

Like an attachment rail?

[civic mirage]

You mean tube/OTA rings?

[thorny jetty]

Yee thems

[thorny jetty]

Basically yeah

Dan my boy from another server don't worry lol

[bold acorn]

yup

[verbal quail]

Are there any flatteners/reducers for the roki 135? (silly question I know)

I'm nitpicking, but if there's a way to fix this glare I'm all ears.

[pallid flower]

You could try to clone stamp it out of existence in PI

[verbal quail]

Would closing up the aperture help? That was shot on F4. 60" iso200

[patent dove]

closing the aperture kind of defeats the purpose of the roki imo

even f4, id try shooting af f2.8

[patent dove]

could be caused by internal reflections, easiest source to test will be the dew shield

[wary jay]

They are flares from the stars themselfs so it wouldn't help.

[verbal quail]

https://cdn.discordapp.com/attachments/1166418542120411237/1203591307667177472/image.png?ex=65d1a6c1&is=65bf31c1&hm=95fe684b04314112232de265e0b19e7df86ceff8ee7e1f34a019e72220678aa8&

They're hardly noticeable either way

[wary jay]

Yes, they are much better than mine.

[fallow stirrup]

Let’s go brand new Lamborghini the cop via

[cosmic marlin]

First non cursed squid nebula I’ve seen

[gleaming flare]

what about jimmys

[cosmic marlin]

Haven’t seen it

[verbal quail]

Why is it normally cursed?

[cosmic marlin]

squid is basiclly painted in, in most images

[patent dove]

found it #247347265226801153 message

[dusky coral]

Should I get it

[uneven compass]

Yes

[uneven compass]

Very excited to do it this summer, likely will be my main project

[thorny jetty]

I'm very excited for the dragon in Sadr

[uneven compass]

Tried it over the summer with my lenhance, kinda mixed results ngl

[thorny jetty]

Looks good

I'm gonna do a big mosaic of it

[slow tinsel]

another lil guy from the roki

[crimson goblet]

First light with my rokinon 50mm (yes I'm an impostor)/224mc, only 1 hour under the smoke of the chemney and quick process in ps only but I'm pretty happy

[slow tinsel]

i love this little crop using @lone tendon 's composition

[lone tendon]

Nice

[slow tinsel]

the resolution is just a bit dead cuz 50x crop

[crimson goblet]

Shot through cheminey smoke and I had to deal with strange strong patterns on most of the frames so it's by no means a great shot but the idea is there

[cunning escarp]

couldn't you just move 10 feet

[verbal quail]

Just wanted to push exposure time to the limits.
Stock Canon T6 (1300d)
Roki 135 (duh)
Ioptron Skyguider Pro
ZWO 120mm cam & 30mm guidescope
13 x 300s lights
12 x 300s darks
iso 100
6 day moon

[verbal quail]

https://cdn.discordapp.com/attachments/1034560628129546310/1208080081982066688/image.png?ex=65e1fb40&is=65cf8640&hm=caa956adedf4c886a671ace61125dc75d257f685795ab0ba0892a2204d5f5c46&

Much better processing

[uneven compass]

Looking good!

I highly recommend you get a whole lot more data, and you really don't need darks either

[wary jay]

NGC 7822 (the question mark nebula) is such a nice fit for this lens! I know the processing I've done is bad, but the starless version shows better the extent of the nebula. 60mins with the Samyang 135mm @f/2 and an unmodified Olympus E-PL5. Bortle 3-4 sky.

[verbal quail]

Oh I will. I wasn't even intending to take any photos that night and just wanted to set up my guide camera. Got the thing up so fast I had an hour to kill.

[nimble stone]

roki :))))

[thorny jetty]

Imposter

Anyways, 30hr ± 1hr data of m81 stacking

[verbal quail]

What stop do you guys use? I've been using f/4

[nimble stone]

f/4 is overkill

2.8 is what i use and find it to be the best

[distant dune]

Is this some sort of upgraded version?

I mean at that f ratio it's basically a small telescope, right?

(I calculated that the minimum aperture for that f ratio is 75mm)

[distant dune]

Oh my god I watched some lens reviews say that the image quality is insane.

When I get a full frame camera I'm definetly buying this

[patent dove]

yeah it has auto focus, I think they make it for Sony only

[nimble stone]

meaning it is useless

af is not needed for ap and an extra like 2 mm of aperture is not gonna help

[patent dove]

autofocus is not useless for AP as long as it’s used with AP software

[gleaming flare]

most camera lenses dont support af control from pcs

im pretty sure some canon cameras and lenses actually support AF though

[patent dove]

yeah, the sigma 135mm would probably be better than that upgraded roki too

yeah I guess sony AF is finicky with AP software

canon works well though

[grave marten]

There is a NINA plugin for canon AF
https://github.com/rennmaus-coder/Camera-Lens-AF

[gleaming flare]

Yeah ik thats what im talking about

[chilly ingot]

yeah theres a nina plugin with using a canon dslr + af lens

praying jesus that someone would stock some astromechanics controllers 🙏

the lens focus motors are super accurate and fast for a vcurve

[thorny jetty]

I love 2!!!

[verbal quail]

I heard 2 can be hard to focus

And that stars bloat more on 2

Is that true?

[thorny jetty]

Yeah I take my stars at F/8

Might start doing 30s instead of 120s for stars too

[verbal quail]

You take stars and nebulosity separately?

[thorny jetty]

Yeah

Just to rid myself of that chromatic abberation

[verbal quail]

What size / brand of filters fit the 135? Regular camera filters, like diffusion.

[thorny jetty]

77mm on the rokinon website

https://rokinon.com/products/135mm-f2-0-full-frame-telephoto

Lists it at 600 so idk

[wicked beacon]

Guys is this measurement right?

[short charm]

I'd have to check myself after unpacking things, but there's also stls of the mask available online already
https://www.thingiverse.com/thing:2168672

This is what I printed and used for a while

[wicked beacon]

Thats for the lens hood right?

[short charm]

Yup

[wicked beacon]

Printing!

[grave marten]

Rock'n On 135 gone mono.

[uneven compass]

@grave marten

Wanna join a cult?

What cam is that?

[grave marten]

294mc-pro

err mm

[uneven compass]

Hmm

Not sure if that will work actually

[grave marten]

I am sure

[uneven compass]

Do you know your pixel scale?

Nah I mean for the cult lmao

[grave marten]

3.6 bin1

[uneven compass]

That's probably fine, we can always down/upsample. There's a group of us with rokis who work on big collaborative projects (our next one should be out soon!) If you're interested in joining, lmk and I can send you the link

[grave marten]

its fine, i mean, people shoot on DSLR with fatter pixels so...

[uneven compass]

Yeah, my only concern is how well it will it will combine with other data (our images are based around the 533/571). Nothing wrong with big pixels at all.

Once again just lmk, I'm sure we can make it work

[grave marten]

my original plan was a for a dual 135/IMX571 OSC since I have a pair. (ignore the 585 dust covers) one with Ha/OIII the other Sii/Hb. But just havent had the time or the skies to dink with it.

[nimble stone]

you can do the math on resample fwiw

and match the resolutions

[uneven compass]

Mhm, I'm assuming downsampling would work. My only concern is that it could decrease the overall sharpness but I doubt it would be significant if that happened at all.

[hazy copper]

Most our targets are big and faint. Not very sharp. If he Bin2d it would be ok enough. Bin 1 should be slightly sharper.

[patent dove]

this would be sick

[split willow]

does anyone have a backspacing plan for a 44/44.5mm backfocus + mono setup (roki 135 + 1600mm)? @civic mirage perhaps

[chilly ingot]

Depends on the cam. I figured one out for touptek 571

i might need some m54 shims though. Gotta get the aliexpress set

https://www.aliexpress.com/item/1005005114386430.html?spm=a2g0n.productlist.0.0.7d234e98xp3UiA&browser_id=9c9b20b3f22f425baad7de558b23b6d3&aff_trace_key=773d1c75cf6b435784b94e7315bb65d0-1692167832195-03072-UneMJZVf&aff_platform=msite&m_page_id=xbphlwauyycavjai18dcb52e3eb876f3ae01c44a69&gclid=&pdp_npi=4%40dis!EUR!3.00!3.00!!!3.17!3.17!%402101c5a417085132235043901e9ae7!12000031707273043!sea!FI!4564986712!&algo_pvid=486ddeec-02d2-470f-ad66-a3d31a0e84cd&_universallink=1&m_page_id=xbphlwauyycavjai18dcb52e3eb876f3ae01c44a69

These are amazing got lens backfocus shimming

They sell a set of 9 in T2, m48 or m54

[split willow]

Well, I archived it once before but I cant really remember the setup…

[chilly ingot]

For the smaller housing zwo cams with the removable 11mm t2 piece there is a setup

And the bigger cams have a different one

[grave marten]

#1059854397301063740 message

[thorny jetty]

HDR sesh has started on M81

Next we going for Ha after these HDR lights

[hazy copper]

How do you blow out the core at 135mm enough to warrant hdr?

[thorny jetty]

F/2 120s gain 220

[hazy copper]

Show linear

[thorny jetty]

I don't have any access ti my subs, I'm imaging right now

https://drive.google.com/drive/folders/1L32kyIruokiNzhOR3XKyvzMspG7R4vqQ

This has both of my stacks

[hazy copper]

Can’t you just turn off autostretch in nina

[thorny jetty]

Yeah

Oh my hdr subs?

[hazy copper]

Your normal subs

[thorny jetty]

Don't have access to them right now sorryz

[hazy copper]

Ight

[thorny jetty]

Will ping you to a screenshot

[hazy copper]

Show hdr then maybe

[thorny jetty]

Debayering?

[hazy copper]

How long are hdr subs

[hazy copper]

Yeah just linear rgb

[thorny jetty]

Nooo the snap can't be saved in chat

I gotcha in the morning

[hazy copper]

Bet

[thorny jetty]

HDR subs are f/5.6, 220 gain 500x15s

Good star data too imo

[hazy copper]

I doubt you need to hdr given your settings. Bright stars might be blown but I don’t think galaxy is

[uneven compass]

I concur with lmc. You're probably using an intense stretch to bring out the ifn, thus clipping the galaxies

[thorny jetty]

Probably yeah

[uneven compass]

Best way to avoid this is with masks or an hdr script

[thorny jetty]

Rockingflyer said it was tricky too

I think this is with no processes in GHS

Spcc (maybe?) Dbe and starnet were used though

[chilly ingot]

[thorny jetty]

Nooooo

[thorny jetty]

https://drive.google.com/drive/folders/1L32kyIruokiNzhOR3XKyvzMspG7R4vqQ

[wicked beacon]

Can someone tell me it this look ready? Will I have focus problems?

[uneven compass]

Looks good to me

You will need to play around with it a bit

[wicked beacon]

How about Backfocus?

[crimson goblet]

What's your lens's mount?

I didn't had enough backfocus with my Sony E rokinon but simply putting an UV/IR cut (which is nice to have for these lenses anyway) fixed it

[wicked beacon]

Mine is canon EF

I also have a uv/ir filter threaded on it

[solid raptor]

What did you adapt it with?

[crimson goblet]

A 3d printed adapter

Works pretty well for a cheap pla thing

But I'll print another one that has an M42 thread, right now the filter is floating around between the ccamera and the lens

[solid raptor]

Schrödinger's filter

[wary jay]

40 minutes of Heart and Soul Nebula with the 135mm Samyang with an unmodified Olympus E-PL5. Even the Maffei galaxies are visible to the left of the Heart Nebula. Edited with DSS and SIRIL with starnet++.

[summer kernel]

Info? This is amazing

[grave marten]

🔭 Rokinon 135mm
📷 ASI294MC-Pro
🔴/🔵 Antlia ALP-T Ha/Oiii Duoband
⏱️ 3.8h

[nimble stone]

you 10000000% should get some bb data on this. this is some really deep ha data

[grave marten]

if the #cloudocalypse ever ends...

[nimble stone]

fair point lmao

[uneven compass]

I might get a break in it tomorrow

Aside from that, next week so far looms promising

[wary jay]

Comet Pons-Brooks yesterday with the Samyang. 16.5 minutes in total from a Bortle 4 location.

[chilly ingot]

Is this full fov of the 135mm or cropped?

How big sensor?

[wary jay]

It is a M4/3 censor. I have the celestial coordinates grid to get a better idea of the size of the comet and its size.

[chilly ingot]

Yeah i was planning to use a 300mm lens and 1” sensor so i might need to swap the optic

135 or 200mm i guess

[wary jay]

With that focal length you will get a nice view of the coma and brightest portion of the tail.

Still a nice frame

[wary jay]

Look how it looks with a framing close to your set up #1160693147521777715 message

[chilly ingot]

Yeah ill do some measuring as i assemble my OTA tonight

Faster 200mm f2.8 lens is tempting

[solid raptor]

Sup fellas I got me a pretty cheap idas nbz but it comes with a rasa di filter holder. Now that does work with the roki but to take broadband data I always have to diasassemble the entire image train and readjust backfocus and thats a pain in the bum.

I was wondering if any of you knew a way to remount the idas nbz (diameter: 49 mm, thickness: 2,5mm) into a standard mount so I can use it in a filter drawer with a uv/ir cut?

I couldnt find a mount that holds 49mm filters as of yet, but I thought that y'all know better

[wary jay]

Isn't idas nbz a 2" filter?

[solid raptor]

https://www.firstlightoptics.com/idas-filters/idas-nbz-uhs-di-filter-rasa8-filter-drawer-set.html

I have this, got it rather cheap used

[wary jay]

It mentions that the filter drawer has M42 connections.

[crimson goblet]

Just curious, for how much did you get it? I'm thinking of buying one as well but can't pay the full price

[solid raptor]

I think I got it for 300+ €. It was unused so I think that was a decent deal

[solid raptor]

Yes it does, maybe read my first message again

[wary jay]

Can't you use the filter drawer without a filter in it?

You can't change filters?

[solid raptor]

I'd have to have a camera with an inbuilt uv/ir cut filter and would have to tape the gap and readjust back focus by about 1mm

[chilly ingot]

If i remember right. The filter glass in this wont fit a 2” filter cell frame

if you buy a blank cell to make it 2”

Thinl they are using the 50 - 52mm filter stock for these or something

[solid raptor]

Yeah the TS ones definitely don't fit

[solid raptor]

And the 49mm will fit? I'll take another look

[chilly ingot]

Do you need a nbz in particular? I have one ill part ways with

im swapping from osc to mono.

[solid raptor]

I need a high speed one for the roki

What do you have in particular?

[chilly ingot]

i got the f2 and slower version

[solid raptor]

Also an nbz or?

[chilly ingot]

yeah

[solid raptor]

Shot you a pm

[chilly ingot]

i think now they make a UHS version for like f1.4 lenses and a nbz EX for other OTA’s

[solid raptor]

Lads is there any narrowband target that is more or less bright we can image around this time of the year in northern skies?

[chilly ingot]

heart & soul and maybe elephants trunk

depends what time are you imaging. Cygnus area is rising past midnight to decent height

[solid raptor]

Yeah northern targets are in a light dome but I might give em a shot

[nimble stone]

alpha camelopardalis if north enough

[summer kernel]

Jellyfish Nebula for a few hours after sunset

[solid raptor]

Thanks for the suggestions

Also I would like to direct your attention to this
https://discord.com/channels/794642864218439681/1222596367705444442

Roki users get a discount 😀

[small scaffold]

guys I'm planning on getting a roki 135 and the nikon z50 with an adapter, will the adapter cause problems? I'm in need of serious help plz

a simple adapter like this should work right?

https://amzn.in/d/bSjjivl

[verbal quail]

Any recommendations for an adapter to hook up my astrocam? It uses M48 not M42

[solid raptor]

If your lens has a canon mount I'd recommend this https://www.firstlightoptics.com/adapters/astro-essentials-samyang-lens-to-m48-adapter.html

If not, then a 3d printed version from thinkable creations https://www.etsy.com/de/listing/1550779704/m42-adapter-fur-color-astronomie-kameras?click_key=a67d5267cbd7722ebd0c1e45c19627d0f4089786%3A1550779704&click_sum=8c10393f&ref=shop_home_active_6&pro=1&sts=1

Or you get a fitting adapter according to your lens mount, from ZWO for example

[cunning escarp]

o.pò

[verbal quail]

Any way to attach this without needing to take the canon mount off the lens?

[solid raptor]

As I said, search zwo canon eos adapters on google, you'll find a lot

Some have an integrated filter drawer

[chilly ingot]

Welcome @old goblet

[old goblet]

Thank you 🫡

[small scaffold]

just got my samyang

here are some images i took with it

moon the milkyway core is 2 sec exposures

and the leo triplet is 16 minutes at b6

[slow tinsel]

i love roki

(this is a crop from my rho image btw)

[cosmic marlin]

👀

[thorny jetty]

I’m excited for summerrrr

[cosmic marlin]

weird seasons and basically tis already Rho season

[slow tinsel]

yeah has been for a while

but nows when you can start getting full night runs on it

(in 'straya)

[pine beacon]

Southern Hemisphere is cheating

[smoky salmon]

turn the earth upside down

[slow tinsel]

our galaxy selection is dogshit tho

[pine beacon]

Yeah, kind of

[cunning escarp]

yall get 2 naked eye galaxies wth yall talking bout

+better milky way core

[slow tinsel]

tf u mean

which

milkyway ??

and if u mean centaurus A, its not visible to the naked eye unless you have EXCEPTIONAL vision and are in a bortle 1

oh wait im a dumbass

magellanics oops

[cunning escarp]

these things?

[slow tinsel]

i revoke my previous statements mb

[cunning escarp]

i guess they're dwarf galaxies but thats besides the point

[slow tinsel]

😅

[chilly ingot]

47 Tuc

so cool

[slow tinsel]

47 tuc is indeed a cool glob

[cunning escarp]

damn southerners with their several easy naked eye globs

[chilly ingot]

what was the other big glob in the south

or was it even the biggest

[slow tinsel]

omega cen

i meant to reply to @chilly ingot btw

[chilly ingot]

oh ye that big ol thing

[slow tinsel]

omega cen is kinda elliptical lookin so its easy to distinguish

i might shoot tonight if weather good

and if im not aurora chasing still

nvm the wsa enlil updated and doesnt look like anythings coming this way

[cosmic marlin]

G3 moment

[slow tinsel]

tonight??

or last night

ik last night was strong

[cosmic marlin]

4am iirc

[slow tinsel]

yeah

did u see it

[cosmic marlin]

sadly no

[slow tinsel]

i slept thru :(

[small scaffold]

#turntheworldupsidedown

[small scaffold]

you need space night vision 💀 exceptional eyrs won't do it

[civic mirage]

Don't you have sculptor?

Love that galaxy

Not naked eye though of course

[slow tinsel]

this your photo?

looks epic

[civic mirage]

It is

Older one though with the z61

And 1600mm

[sage pivot]

It’s been clear nonstop lately!

[grave marten]

Im planning to goto Pyramid Tuesday night (new moon)

[old goblet]

first finished image with 135 f2 || @chilly ingot ||

[sage pivot]

I am unfortunately ill right now, otherwise I would’ve been up there for the past week with my aunt

[grave marten]

Well hopefully you feel better soon. If you do, reach out at we can meet up for a shoot. Friday and Saturday looking decent cloud/seeing wise but have a touch of moon.

[sage pivot]

I’m almost done with my 100 hour SVX first light

[grave marten]

Hell yeah. ping me when you share the final

[sage pivot]

Should get to finishing the data acquisition this week. I’m gonna use my 1on1 with Ryan for the processing I think

[solid raptor]

Now I know why I've been clouded out for a month, that fella is stealing our clear skies

Tbh idc during galaxy season as long as we get cs in summer

[sage pivot]

Reno baby 270+ average clear days

Just horrible seeing always : )

[solid raptor]

Zamm

[solid raptor]

Partners in crime

[sage pivot]

He’s like 20 minutes north of me

[solid raptor]

So much green honestly hurts my eyes

[grave marten]

yeah the seeing has been trash lately

[sage pivot]

I can’t really say I ever remember having good seeing here ngl

Lots of hours watching saturn look ringless through my dob

And Jupiter looking like a brown ball with no details

[solid raptor]

Why's the seeing so trash?

Oh wow. Guess it's time to feast

I mean adjust my backfocus for another few hours

[grave marten]

Finally got around to it and mounted the EAF.

[grave marten]

Roki deployed out at the dark site.

[grave marten]

initial pass on roki data

[grave marten]

Feeling better? Putting together another run out to Pyramid tonight. Might be able to catch aurora as well!

[sage pivot]

I’m going to Oakland in a few hours 😞 I’m not even be able to image for this weekends clear nights. Even though they’re the first forecasted good seeing since I’ve had my SVX

[grave marten]

RIP

Other than a growing moon, we got a nice lineup forecast

[sage pivot]

I’m seriously so upset

It’s for my parents’ engagement party which is cool in concept but in reality I’m just going to be in the house alone all weekend 😭

Have not had a night of good seeing with my SVX yet. HFR the first night I got it was in the high 2s, HFR lately has been in the high 3s. Last night it jumped around from 2.8-3.9 with round focused stars

I actually had one night where it was low 2s, and the FWHM for that night was all in the 1s

[grave marten]

thats gotta be frustrating, to have your crown jewel ota, and decent conditions...and still not be able to get in a session.

[sage pivot]

To go do some shit I don’t wanna do 😭 yea I’m bummed. I can’t bring up the idea of staying home though it’ll just cause issues

[grave marten]

It just went off

[sage pivot]

AHHHH FREAK MANNN

I WISH I WAS HOME

GOD DAMMIT

Are you at pyramid?

[sage pivot]

Could you see with your naked eyes?

If you say yes I’m

I’m already so angry that I’m not home

[grave marten]

100%

[sage pivot]

I am bawling

[sage pivot]

Are you in Reno or at pyramid

[grave marten]

Pyramid

[sage pivot]

That makes me less sad

[sage pivot]

Might hit pyramid tomorrow if it’s clear

[grave marten]

Was out there tonight... Wwaaay to busy. 1000s of people.

[sage pivot]

Damn bro

Maybe I’m not gonna bring my full rig

[grave marten]

Impossible to image with all of the passing headlamps and tail lights.

I returned home

[sage pivot]

Were there lights going on at least?

[grave marten]

No

[sage pivot]

Damn

[grave marten]

Last night was the night

[sage pivot]

Did you try going further north or east even

If I wasn’t in Oakland bro

Fck

[thorny jetty]

If this is the thinkables mount, what are your eaf settings?

[grave marten]

step size, default 50. really about the only thing I set was to 'reverse'. No problems with the routine.

[thorny jetty]

Okay

[thorny jetty]

What’s the default measurement (hyperbolic, trendlines, parabolic)

[verbal quail]

Oh yeah, it's all coming together

[verbal quail]

*Fixed the back focus after Lux pointed it out

[small scaffold]

don't trust the 3d printed rings btw

mine broke

I was lucky to catch it

I think i printed the same model with 80% fill, mine was a remix of this model

[hazy copper]

I have these exact same rings. They will never break. The lens will break before they do.

I do however have a metal dovetail

[small scaffold]

can you tell me how you attached them, also send me the files for the prints?

[hazy copper]

I got a aluminium block and milled down angles on the edges. Drilled and tapped a hole for the bolts to go in to.

[small scaffold]

Nice

[hazy copper]

Model is the open Astro tracker ring set. Somewhere online.

[small scaffold]

o

[verbal quail]

What stop do all of you use? Will f2 bloat my stars?

[short charm]

Don't use cheap PLA to hold your $100's of equipment

[gleaming flare]

3d printed parts are really strong idk how it managed to break

[hazy copper]

I use 2. A little more bloat than tighter F ratios but it’s certainly manageable. I like the speed.

[small scaffold]

very, f2.8 will work

[thorny jetty]

Yay rokiiii

[short charm]

If the stuff is tuned, then yes. But also I had a CF filament that would bond to anything but to itself, so sometimes you just get some crappy stuff

[gleaming flare]

I thoroughly beat the shit out of all of my 3d printed parts before using them

They have all survived

[gleaming flare]

makes sense

[slow tinsel]

juice

what filter

[grave marten]

Love this area with the Rock'n On 135

[solid raptor]

Is this part of a bigger project?

[grave marten]

nope, just picked an area to run on.

[small scaffold]

what filter?

also modified camera or astrocam???

[solid raptor]

Ah nice. What were you imaging?

[grave marten]

just wanted to capture a vast swath of Ha

Punchy and crunchy. Need more than 4hr

[thorny jetty]

The Chinese l-extreme the sv220

[thorny jetty]

^

I need to run it at f/5.6

[solid raptor]

Quite some Oiii already, even the soal bubble is kinda visible

[solid raptor]

Optolong is Chinese as well

I hope I'll be able to get data on Westerhout 63 this summer, also already visible on your image but I think you have pretty good skies no?

[thorny jetty]

This one is more Chinese

They probably got a kid to make mine

[solid raptor]

https://tenor.com/view/social-credit-social-credit-score-credit-score-score-china-gif-23125701

[grave marten]

My Backyard is a B4-B5

[solid raptor]

Nice. How much integration time do you aim at?

[solid raptor]

Ah and is that an IMX571?

[chilly ingot]

Widefield cygnys so cool with narrowband

[thorny jetty]

Mine is unusually higher than the average American since I high-ball Chinese sellers on their online markets

[grave marten]

Yeah

[small scaffold]

I'm gonna try north america with a stock dslr today, hopeso i get good data

b2 and sround 3 hours

[wary jay]

Does anyone have a weird greenish cast with the Samyang 135mm or is it just me?

Especially with photometric color calibration in SIRIL

[bold acorn]

Why would it be the lens causing that?

Does the glass appear to be green or something?

[wary jay]

It isn't the camera, as when another lens or telescope are used the colors are OK.

[hazy copper]

Likely OSC things. There might be slight CA affecting photometric CC.

[grave marten]

moar data, better balance

[solid raptor]

How much are you at?

[grave marten]

~9 hour

[solid raptor]

How much do you want in total?

[grave marten]

Not sure, Ill probably double it this week (~18h) and see what it looks likes.

this is just fast stacking in DSS, and real simple workflow. Im sure Im leaving lots on the table here.

[grave marten]

The OIII is really picking up now ~12h

[bold acorn]

Ooh

[bold acorn]

I liked it better with this balance of h alpha to oiii

[verbal quail]

What kind of exposure times am I looking at for North America nebula in a Bortle 4?

[bold acorn]

1 hour in total will suffice for a decent image

at f6.3 and a non modified camera i was able to pick up allot at 1 hour

[hazy copper]

As much as possible, I aim for ~15-30 hours as a baseline where im happy. Bortle 3.

[chilly ingot]

well. at f2.8 and narrowband couple hours makes an image but it kinda sucks

would need to multiply that few times

[bold acorn]

bro whoever reacted to my message i said DECENT not great holy crap

like 1 hour at f2 wont give you a terrible image for gods sake

[old goblet]

very much depends lol

[bold acorn]

well anywhere but a city

[old goblet]

depends on the object as well, if houre going for dust like the stuff around iris then 1h is just not gonna be good

[bold acorn]

north american nebula...

[old goblet]

wont be terrible but still noisy

[bold acorn]

hence "decent"

(credits to Luke Aren) 27 minutes at f2.2 with the roki no calibration frames bortal 2

i would call that a decent image

[uneven compass]

Do you know if it was taken with a modified cam?

[summer kernel]

it has to be

that much ha

[small scaffold]

how are u guys running it at f2.2 and f2.4? i can only use it at f2 and f2.8 or higher

[old goblet]

the aperture ring clicks into place between the f2.8 and f2 location, guessing thats where f2.2 or f2.4 is located

[gleaming flare]

Step down rings

Not using the aperture ring

[leaden pumice]

Which ZWO cameras do you guys recommend with this lens?

[slow tinsel]

@hazy copper uses 533mc i think and hes an absolute champ with it

[leaden pumice]

Thank you!

[slow tinsel]

however 533mc is a very small square sensor, so it probably doesnt use all the image circle

also the square aspect puts some people off

but that also means you can use it wide open at f/2 and have tight stars throughout the frame

but you'd best ask him, because i use the lens with a dslr

[hazy copper]

The sensor size sucks, but it is nice having good stars

depends on your budget

Can get a touptek 571 if your roki is nice.

[solid raptor]

I have a question lads.

https://astrob.in/maaf07/0/ This is an image of the molecular clud around lambda ori

40 mins of int with a roki, 2600mc pro and an l-extreme

This is 5-6 hours in winter with a 533, idas nbz and roki as well. I know the stars and colours etc are trash but it was a test shot. But how is it that I have those dark spots everywhere and so little signal compared to him?

I have over 5 times more int (I also accidentally deleted half of my data hut that wouldn't have helped too much I think)

Also, on my phone it looks a lot more saturated than on my laptop so sorry about that

[hazy copper]

dark spots could be your background extraction.
his image is also lower contrast

[solid raptor]

Well I didn't get it much better and neither the graxpert AI. Also I suspect I had my filter in with the wrong side facing fordwards

I've heard conflicting things wether that affects the signal or not

[hazy copper]

Having an image full of nebula makes the extraction and model generation pretty much impossible.

[solid raptor]

Ah I see

[verbal quail]

Does anyone use a Skyguider pro with their roki? How long of subs can yout ake? I don't want to have to bust out the EQ-G every time I want to do widefield.

[grave marten]

I've ran the Rock'n On 135 on the swsa2i. 3m subs no problem.

[verbal quail]

Looks very similar to the SGP

[grave marten]

indeed

[verbal quail]

Could probably handle this just fine then

[hazy copper]

Manual target finding is terrible.

[solid raptor]

I mean @civic mirage made 5 min exposures with a small apo so you should be fine

[civic mirage]

Good way to get used to the sky + if you get a proper fine adjustment dec plate for sgp it's much less aggravating to center targets (I suffered with the original dec swivel plate).

Also makes you appreciate finally getting goto much, much more.

[civic mirage]

Yea your good with the sgp

My payload was slightly above it's capacity

Still ran like a champ

[hazy copper]

That is true. However I hated getting up at 1 am to do a meridian flip or find a new target.

[civic mirage]

Oh definitely, that was my no. 1 issue.

At times I let it go through the night if the target was low to the east or a little before zenith to the west. I got it shut down early enough before it ran into the tripod. But risky of course.

[verbal quail]

Unfortunately SGP doesn't have setting circles

[solid raptor]

Has anyone here used 3d printed diffraction spike masks?

[small scaffold]

facts

[grave marten]

to mute spikes in newtonian imagry? Yup. Used em on my 8" Worked pretty.

[solid raptor]

Actually to emulate spikes on the roki

Hows your Cygnus Image coming along btw?

[old goblet]

you can just put like 2 pieces of fishing line or whatever string in a cross shape in front of the lens and itll work

[solid raptor]

It probably will yeah, but having something like a bahtinov mask that you can just put on it is easier and more consistent I'd say. I have access to a 3d printer, just was curious if others tried it before

[old goblet]

people definitely have, just not sure how many do it with the roki, i know a person here who 3d printed a spike mask for a larger frac, lemme link some of the images

#1205890009526181919 message

[grave marten]

Took a break. I've pulled about 40 hours total. Needs to be sifted through with subframe selector. I think the last processing was at 100x300s of selected frames.

[uneven heart]

U need more o3, i know that because i made the same mistake

Is this osc, well that would explain the horrendous noise

[solid raptor]

So this is only about 8 hours? Keen to see the final image

[verbal quail]

You can mask those out?!

[solid raptor]

I was referring to a physical 3D printed mask you put in front of a refractor to get Newtonian spikes

[verbal quail]

Oh, I thought you meant it in this way for some reason

[thorny jetty]

8lb black braid tied w/ clinch knots

You can get 100yd/m of 8lb braid for like 10 bucks

[small scaffold]

what targets can I shoot with a stock mirrorless and the roki apart from the standard ones?

this is a video i took from the roki at b9

at f2

[bold acorn]

"If your roki is nice" is this phrase talking about like their quality control? I'm a little confused

[hazy copper]

yup, most will be ok, the biggest issue is mounting it without tilt issues and the correct backfocus.

[uneven heart]

Tons, but u said ur in b9 lmfao

So basically none

Cause b9 is ass

[small scaffold]

i can get to b4

[uneven heart]

Then ur in for a great time with a roki i think

[small scaffold]

the video was shot at b9

[small scaffold]

what targets tho

i did rho and bodes

[uneven heart]

Try stuff around cygnus

Or stuff near milkyway core

Idk where ur from so it depends

If u shot bodes prob europe or usa?

[small scaffold]

nah

india

[solid raptor]

I'd say it's a bit better now, stars are shit and denoised af but it was more of a test shot

[slow tinsel]

way better

[thorny jetty]

@open swift nerd this dude

[solid raptor]

Haha thanks but I haven't posted a single image in deep space pics, only WIPs

[thorny jetty]

Well you need you a red name

I’m gonna harass Nick

[solid raptor]

You seem to do that a lot xD

[thorny jetty]

OH YEAH NUCK

I gotta talk to him about monochrome bullshit

[grave marten]

Speaking of monochrome bullshit... Will it djent?

[thorny jetty]

I wish I gave my roki back and got a new one

[solid raptor]

Are you using normal narrowband filters or highspeed ones?

[thorny jetty]

I think the high speed ones would be baader to use than normal narrowband

[solid raptor]

They sure would be but is this a wordplay?

[thorny jetty]

Just a little

Actually how would f/2 narrowband filters compare to normal narrowband filters?

I’m guessing it’s just what you need, like I need normal narrowband filters since my roki is so shit

[solid raptor]

https://youtube.com/watch?v=RSw6vDhSrIU&si=TNqy4V1oGP4-rEGu

It's pretty evident especially with tight bandpasses

[thorny jetty]

Never really been studying about band passes

[solid raptor]

What? 🤔

[thorny jetty]

Like how the f/2 filters work

[solid raptor]

Oh they have a special coating

[cosmic marlin]

The bandpass is just slightly shifted forwards right ?

[thorny jetty]

I’ve just been looking for some to cop, but my first attempt at veil was a reality check

I might just get some cheap 1.25” mono filters with a 533 if I ever do decide to go mono

[solid raptor]

That's how I understood yeah

That's why it only works on the specified aperture ratios

[solid raptor]

On the roki?

L

[thorny jetty]

Sorry brain fart

Cheap narrowband filters

[solid raptor]

I'm just gonna leave this here, sums it all up pretty much

[thorny jetty]

Don’t know from where but yeah

[solid raptor]

Well if I'd go mono on the roki I'd prolly get either pretty wide filters or save up for highspeed ones

At least for Oiii

Mono roki is absolutely sick but idk if the highspeed filters for that would be warranted. Maybe if you get a fast main scope

[thorny jetty]

I could get a Quattro but I’m tired man

[winter herald]

I ain’t ever wasting my time doing allat collimation

[cosmic marlin]

it really isnt that bad

[thorny jetty]

I’d mess it up more than it was

[slow tinsel]

collimation is very easy with bobs knobs

i sound like an ad wtf

[winter herald]

probs isnt but im stupid

[winter herald]

i might get a newt one day but it would cost a lot coz id need a new mount too

im happy with my swsa gti and rc51 for now

[grave marten]

GTi is a solid mount

[winter herald]

fr

if i wanted a newt tho id have to get bigger

[grave marten]

I bet it would do a 5" Newt alright tho

[winter herald]

maybe , id love to get a quattro 150P ngl such a sick scope

[grave marten]

I used to run an 200PDS, was one of my all time favorite OTA tbh

[winter herald]

yeah they're great scopes but i am LOVING my rc51 atm

[grave marten]

For sure. My little Sharpstar 61 gets most of my attention these days.

[winter herald]

haha yeah . my RC51 is my baby , used to have ZS61 but wasnt a fan tbh althought i only ran it unguided and BB so idk how it could of done

[grave marten]

I had a ZS61 and kept the Sharpstar over it.

Still run a ZS81 though! It was my fist OTA, not sure I could part with it

[winter herald]

zs61 are alright but when i got guiding and filter i was already on RC51 so i didnt use zs61

[winter herald]

yeah bonding haha

[grave marten]

Id thought about an RC51, but the Sharpstar is pretty good for me, and comes in at ~270mm f/4.4 with reducer.

[winter herald]

oh nice , yeah if the sharpstar is good defo stick with that

[grave marten]

About the only thing I "want" would be a 12" f/4 newt as an upgrade to my 10" f/5

[winter herald]

12'' at F/4 is amazing ngl

[grave marten]

I run my 10" at f/3.75 and its been great but Id love a 305mm primary lol

[winter herald]

Oh nice fast little thing

[solid raptor]

"little"

[civic mirage]

Muting spikes on a newt is diabolical

[civic mirage]

They're great

[bold acorn]

Woah that's bright

[solid raptor]

Ah nice sure looks very convincing

[leaden pumice]

Question for you rokinon experts. If I get a lens for a cannon DSLR, would I be able to upgrade to ZWO ASI2600 MC later on?

[small scaffold]

yup

[leaden pumice]

Thank you!

[small scaffold]

has anyone tried elephants trunk with the roki on unmodified cam?

[slow tinsel]

that won't be good, go for broadband objects if youre unmodified

or better yet get modified or astrocam

[small scaffold]

i wanna try cygnus

what i was thinking is that I could maybe apply hubble pallete to my osc images

and spend like 2 to 3 hours at f2.2 or 2.8

with the roki

[hazy copper]

Doesn’t work that way. You need 3 channels of narrowband.

[small scaffold]

ou

[old goblet]

just keep it osc, hubble p is 🤮

[hazy copper]

broadband bestband

[chilly ingot]

Or sell S3 filter

[slow tinsel]

i hate hubble palette except for a select few targets with very distinct Sii emissions

then it looks nice

and hot take, foraxx sucks

[civic mirage]

I used to really like foraxx, but now it's just meh. If done really well and on certain targets it can be neat.

[small scaffold]

what's foraxx?

[slow tinsel]

it's a palette that's basically looks like dark orange and blue

[patent dove]

speaking of Foraxx palette... WIP, still need more data to control the Oiii splotchiness

[civic mirage]

That's sick as hell

[small scaffold]

ou

[slow tinsel]

alright fine, it OCCASIONALLY looks good

maybe ive just seen too many absolutely done-in foraxx images

[civic mirage]

Yea it has the ability to look great

[grave marten]

Last year's Crescent Nebula in foraxx inspired pallet

[patent dove]

I agree it can only look good in certain regions, just like SHO. I think it fits really well here

HOO pretty much always looks good though

[small scaffold]

how do you achieve such pallete? is it possible in ps??

[dire flicker]

yes

[small scaffold]

howso

[dire flicker]

you do narrowband?

[patent dove]

@civic mirage inspired, lol, not a proper process, just the OHH combo

[civic mirage]

Dayum, that's actually insane looking.

[grave marten]

guessing a mosaic? how many panels?

[thorny jetty]

🐉

[patent dove]

3 panels, up to 2h20m each

(5nm dualband filter)

[grave marten]

sic

[grave marten]

Rho from B1

[elfin nimbus]

anyone have tips for settings in Nina for the EAF with the Roki/Samyang 135?

[small scaffold]

what camera and mount? also exposure time?

[grave marten]

AM5, Imx571, 100x120s

[small scaffold]

3 houes

very nive

nice*

[verbal quail]

What kind of integration time am I looking at for Rho Oph in a bortle 4

[hazy copper]

21.5 hours here. I would say it’s workable at 15.

Heck probably workable at 10 if you have a clean sky.

Most of this data was shot at 60-90 degrees altitude

[verbal quail]

Thing only rises to 22 degrees here

[hazy copper]

They I would say 20 hours with a dark horizon

[verbal quail]

What cam?

[slow tinsel]

thats beautiful

is that the same set i processed?

[verbal quail]

You pinged me instead of LMC 🙂

[slow tinsel]

oh shit mb

yeah dw about it

i just cant rmb the integration of the one i processed

[hazy copper]

533mc

[civic mirage]

That's delightful, only thing id do is watch that darkest area of the dust. Looks slightly clipped. But you may not be finished with it idk lmao.

[hazy copper]

I guess I need to mask that then. It’s unavoidable if you want the real background to be acceptable brightness.
This was a half edit too.

Well, finished edit but I wasn’t happy with it.

[civic mirage]

Yea I feel like the contrast will still be good, that area is darker than the background anyway.

[patent dove]

you could try applying an stf to a preview of the dark part and then applying that stf to the whole image to preserve it

[small scaffold]

hey, if anyone else has shot the rho opphuchi with roki on a apsc sensor, lmk, I wanna try merging other people's data with mine to see how it turns out

[small scaffold]

why not f2.2?

[hazy copper]

It’s not noticeable in sharpness gain, noticeable in snr drop.

[slow tinsel]

shot it full frame, but my signal is very clean, with good contrast from bortle 2. detail is good too here's a crop

[elfin nimbus]

I only have 20 minutes of data on rho, I'm waiting a little further into the season for it to get higher where I am

This is what I had so far, full frame at f/4 in bortle 4 sky

[leaden pumice]

Do you guys have any recommendations for a IR cut (ha pass) filter?

[grave marten]

Was kinda bummed. Go out of state to B1 skies for star party with one of the main goals to run on Rho for a few hours...and I get high clouds.

Image still turned out decent... But I know was sub optimal

[old goblet]

the hell is mpeg

[slow tinsel]

mustyahh picture eg

[bold acorn]

Woah epic, why is crescent pure blue though

[thorny jetty]

He likes the color blue

[grave marten]

Think it's just lost in translation at this image scale and resolution. Make no mistake, there is plenty of O3 signal in the region, but when we crop in, we see a more familer distribution.

[elfin nimbus]

does anyone know of a bahtinov mask for this that works down to f/4? The one I use works fine at f/2.8 but the middle spike disappears at f/4

[chilly ingot]

If you focus at f2 or 2.8 the lens should still be in focus when you click it down

Or just take a longer exposure or find a brighter star for that f4

[elfin nimbus]

Oh interesting I didn't think focus would hold the same

[bold acorn]

Looks cool

[chilly ingot]

its has been that since the film days. Focus wide open, stop down for the picture

but astro stuff usually needs some special attenion or double checking

thinking that you are focusing precicely at infinity and dont need to be somewhere in the middle of some other distance's depth of field

[thorny jetty]

Focus will actually be better

Than if you baht’ed at f/4

[elfin nimbus]

Don't get too many clear nights so I experimented with adding data from an 85% moon session with a previous no moon session. GraXpert totally cannot handle the moon gradient and leaves a weird artifact. The result is interesting, the galaxies in the image look a lot better with the extra data but a lot of fainter stars are drowned out making the overall result worse

[small scaffold]

@hazy copper u use roki at f2 right?

does it just bloat the stars or the nebula too?

coz if it's just thr stars then some blurx should do it right, it's good at f2 for max light gathering

[slow tinsel]

if stars are bloated then so will everything in the frame, the lens doesnt choose what is gonna have aberrations

[slow tinsel]

its obviously more visually apparent in stars, since they are just points of light

[small scaffold]

ou

[small scaffold]

ahh

okay

[uneven compass]

Its a trade off. You really can't know if it's the best option for you until you test your lens. I image at f2 as well and it works great for me

[small scaffold]

mine works too but the stars are weird shaped

i never tried at f2.2

ill try if that fixes the the dtars

f2.8 is sharp

[uneven compass]

You can always retake stars separately as well

[grave marten]

Interesting comparison. Rho from B1 dark site (GSSP) ~3h away (100x120s) vs Rho from B2 dark site (PYRAMID) ~45min away (80x120s). B1 Rho nekid sensor, B2 Rho additional UV/IR. Cant say for sure if both were shot at same f/ratio. I feel B2 was shot faster, just due to ca in the stars.

I would also note, B1 did have high thin cloud obstruction

[fallow stirrup]

Pyramid has a better dbe

[elfin nimbus]

First testing on Andromeda from up North in Michigan at around Bortle 2.5

~42 minutes total integration so far

[thorny jetty]

Bloated stars kill.

[slow tinsel]

aside from the obvious, this would be a much better composition if u used the same dbe points, or better yet MSGR. on the left one the antares region is VERY oversubtracted. right looks fair bit better, but if it's shot faster that makes sense

[spark wraith]

Untracked Orion nebula

-sony a3500

-samyang cine T2.2 135mm about 2600subs at 1.3 sec exposure

old photo that I tried to process couple of time and this Is my best attempt yet

[dire flicker]

Very clean

[spark wraith]

thx

[dire flicker]

quite similar to mine

[spark wraith]

you should try this it helps a lot but if you go to far it starts getting weird

lightroom

[dire flicker]

interesting. havent used that denoiser

[cunning escarp]

seems to really like faking stars

[civic mirage]

It's not the ideal way to denoise, but if that's all that's available then it can be useful. I would apply it VERY lightly tho to preserve as much detail as possible.

[wary jay]

K. Sokolovsky discovered on 29 July a nova in Vulpecula, V615 VULPECULAE, using a 135-mm-f.l. f/2.0 telephoto lens in the course of the "New Milky Way" (NMW) survey.
The nova has a magnitude of 10.

More info here: http://www.cbat.eps.harvard.edu/iau/cbet/005400/CBET005423.txt

[chilly ingot]

Leica R 180mm f3.4 APO wide open

zero CA. Superachromat lens

costs the same used as a roki brand new though

[civic mirage]

Wtf

[gusty rock]

What did you image with it ?

[chilly ingot]

a little bit of veil

[gusty rock]

How good did it come out

[chilly ingot]

@civic mirage this is from the first 5min sub

[chilly ingot]

noisy and low signal. i dont have super dark skies and nights are still short in the north

[hazy copper]

What sensor

[chilly ingot]

just a 533

[old goblet]

dayumn

[chilly ingot]

dont like how this turned out

1.5hrs in nautical dark + civil dark using a 4nm dual narrowband

[civic mirage]

Yea looks about right

Just needs around 10hrs integration

[chilly ingot]

yep. my last years veil pic was with a the z61 at f4.8 and used same filter

half the speed, double the signal

@civic mirage now im wondering if i should try widefield narrowband cygnus area using a 50mm lens

[civic mirage]

Would be neat

[chilly ingot]

something like this

[civic mirage]

Ooo ye

[chilly ingot]

@civic mirage this lens still impresses me. It has no fluorite since its expands/contracts with temps too much.

This sucker kept focus all night

German gigachad made his own glass mix

[gusty rock]

Joining the gang in a few days

[bold acorn]

Did u stop down

I was looking at results from my boy @thorny jetty and this lens seems absolutely terrible wide open

[chilly ingot]

No its wide open

[bold acorn]

Damn

So the roki lottery is true

[chilly ingot]

This is Leica lottery. Not a roki

Mono sub

[bold acorn]

Well his images look absolute cheeks with coma chromatic aberration and everything

[chilly ingot]

This vintage lens costs same used as a brand new roki

[bold acorn]

What the

[bold acorn]

Wait so that's not a roki?

[gusty rock]

No he said its a leica something go further back in the conversation to see its name

[chilly ingot]

Leica R 180mm f3.4 APO

form the 70s

[thorny jetty]

Don’t crack it wide open if your shit sucks

[chilly ingot]

Yep

If it sucks still. Warranty it

[bold acorn]

Oh well I didn't read and i thought it was a roki because yk this is the thread specifically for rokis

[gusty rock]

Ikr, surprised me too at first

[chilly ingot]

I just spam here some general camera lens imaging stuff

Sorry

[gusty rock]

No worries imo mate

[small scaffold]

any target suggestions for winter, dslr not modified amd apsc

except the usual orion n stuff

[gusty rock]

Ifn in general is a good option for unmoded cameras

[bold acorn]

why roki + unmodded

why not mod it

[dire flicker]

bc you cant effectively use it for daytime

and AF wont work

[hazy copper]

You can use it for daytime no problem.

Autofocus works fine if you can get the sensor at the right level

[small scaffold]

my camera is too expensive for me, and I dont want to risk modding it

thats the problem

[small scaffold]

any other targets?

[solid raptor]

Pleiades

Also I just realised that this forum was created on my birthday

[small scaffold]

will do that

[summer kernel]

I use mine all the time during the day it it works fine

[gaunt scroll]

can i get sugestions on what to shoot with my rokinon if i live near Brasov?

[gusty rock]

Cygnus région or pléiades

[elfin nimbus]

3.5 hours on Andromeda so far, definitely want more data on this

getting the color balancing anywhere near happy on this is acting very hard

[elfin nimbus]

now with 5.5 hours

[gaunt scroll]

thx for the sugestion

[gusty rock]

No problem, happy you shot what i suggested !

Im shooting polaris ifn tonight (no need for a tracker if i shoot 20s with ballhead)

Allows me to do a quick session with short time to set up and leave

[elfin nimbus]

Very noice

[gaunt scroll]

great target, I did it befor with this lens. I suggest you get at least 2.5 hours

[gusty rock]

Only could get about 1hr

[gaunt scroll]

No problem, GraXpert does wonders

[leaden pumice]

Why would you want to use F4 instead of F2? I’m curious as to why you’d want to step down from F2

[gusty rock]

Idk what you are answering to, but when its at f/2, all the defaults of the lens are revealed

[gaunt scroll]

what do you mean by "all the defaults of the lens are revealed"

[gusty rock]

I mean coma and CA may appear depending on the quality of the lens

[leaden pumice]

So based on that, I would rarely want to use f2?

[gaunt scroll]

The rokinon 135 has low aberration even at f2

[gusty rock]

Prople mostly shoot with it at f/2.8

[gusty rock]

Coma is another thing tho

[gaunt scroll]

this is a corner of one of my images. The elongates shape is from the tracker

[gusty rock]

If thats from the tracker shouldnt it be elongated on the whole image ?

Unless you are shooting polaris cause it rotates if im not forgetting anything

[leaden pumice]

Guided?

[gaunt scroll]

it is

[gaunt scroll]

no

[gusty rock]

Depends on your copy i guess

[leaden pumice]

I’ll be getting my rokinon today so I’ll be testing it tonight, well see how it goes! Thank you guys for the info!

[dire flicker]

some people also use narrowband filters where you cant shoot at a fast ratio bc youll get band sshift unless you buy a high speed filter but are sometimes more expensive than the traditional filter, hence people stop down the lens

[leaden pumice]

Ah I see, thank you so much! I noticed how some pictures are shot at f2.8 and higher and wondered why. I wanted to be ready for my first night so this has been very helpful.

[thorny jetty]

f/5.6 narrowband with the roki is amazing

[cosmic marlin]

I just use narrowband at f2.8, same as broadband cuz if I go below that it's just all noise

[crimson goblet]

Be careful tho, at high speeds most narrowband filters suffer from bandshift

You might have better snr by stopping down a little

À least on Oiii

[cosmic marlin]

ive tried all the way down to F5 and its just more noise then signal its painful

[crimson goblet]

The bandshift impact depends on your filters bandwidth so ig 2.8 might actually be the best

6 nm?

[cosmic marlin]

Think it’s either 5 or 7 can’t remember

[buoyant cliff]

First try with my Samyang 135mm + Sony A7III as I'm waiting for my 294MM Pro to arrive. Just about 2 hours of exposure. Very excited to shoot with Bin1 47mpx mode. Till now I had 533Mc pro which is definitely not good choice for this lens so I didn't even try.
My friend made me a custom M48 adapter to that lens. I removed whole Sony E mount back and replaced it with that adapter which is much shorter than original e-mount. According to my calculations I should be able to fit filter wheel there.

(tape is just for locking the aperture 😄 )

[crimson goblet]

It might be that your filters are already a bit preshifted

Idk

Some people had issues with that

[thorny jetty]

I wonder how you can make a dovetail bar for the thinkables mount

I don’t like the plastic one

[leaden pumice]

First light with the rokinon
F2.8
25S 82 minutes total
Guided

I did have issues at high exposures, I had to bring it down to 25 second exposures. Around 60 second exposures were pretty much just white, is that too long for the lens?

[small scaffold]

no, its due to the light pollution

I took 1.5 min exposures which were dark in a low light pollution site

[leaden pumice]

Ok great! I took it out again tonight and have it pointing up at C20, currently taking 60s exposures and it seems to be good!

[small scaffold]

cool

what's you're setup?

[leaden pumice]

-Sky watcher star adventurer GTI
-Rebel t7 - going to be getting a full spectrum t3i soon
-ZWO ASI120mm + apertura guider

[small scaffold]

oh very nice

I have a similar setup, with a unmodified camera and the roki

how are the subs turning our for the NaN?

[old goblet]

guessing youre in a pretty light polluted area to be getting blown out in only 60s

[small scaffold]

yeah

[leaden pumice]

NaN?

[small scaffold]

c20

north america nebula

[leaden pumice]

LOL. Good so far! I’m in bortle 4 actually so I normally get good subs at 60s

[small scaffold]

is c20 visible in single subs?

[leaden pumice]

Nope, I’m about to get 2 hours worth of data though so we’ll see how it turns out. I’ve been using Deneb to make sure I’m in the right area

[old goblet]

interesting, im in b4 as well, ive shot pleiades into the light pollution dome and got away with like 2min subs at f2.4

[small scaffold]

oh nice, you should use nina for imagong then

it'll platesolve and get to your target

[leaden pumice]

😳 maybe the camera? The lens seems to be fine, no issues with the subs or anything. I guess I’ll find out tonight whether long exposures with an unmodified dslr is a good idea or not.

[leaden pumice]

I’ve been using APT, haven’t really looked into NINA. I’ve been messing with dithering in APT, haven’t even looked into plate solving yet

[small scaffold]

oo

I prefer nina coz i dont guide, and i can dither without guiding in nina

[leaden pumice]

I went over my data from last night, the 60 second exposures are fine. They are white in the camera preview, but theyre fine when you open with Siril or other astrophotography software. Link for subs if you want to take a look: https://drive.google.com/file/d/1C7JHN0TfQOQ8QfjryB4PBRRNjEONfLEf/view?usp=sharing, https://drive.google.com/file/d/1O32hnuYfWYUGUQDJTPg2SozOJ70eEP5x/view?usp=sharing

[crimson goblet]

I've just ordered my rokinon 135

[spark wraith]

hope you win the roki lottery

[small scaffold]

anyone imaged the triangulum with the roki? is it worth it ?

[crimson goblet]

I've seen some do it and I'd say it's worth it

[crimson goblet]

Yep, finger crossed! There's a 2weeks free return for any reason anyways

[chilly ingot]

2weeks of cloud coverage

[bold acorn]

yes u can

[bold acorn]

my sensor was absolutely knocked off course and autofocus works fine

it literally moves the motor

until it focuses

I do daytime with my camera all the time after modding

sure I do have to fix the red tint in post processing

only because I'm not bothered to fix the white balance

[grave marten]

I usually shoot at f/2.8 sometimes f/4 sometimes f/2.0. Here is a collection of various targets with various camera/filters. Band shifting hasn't seem to been an issue even at f/2.0

[bold acorn]

I can see it

it's like a ring

good photos tho

[gaunt scroll]

what bortel scale are you shooting from

[gaunt scroll]

What are those, around the stars, like a halo of gas?

[grave marten]

Just Halo

[leaden pumice]

Bortle 4

[leaden pumice]

These are amazing!! I’m assuming you’re using a ZWO camera?

[grave marten]

These are using dedicated astro cameras, Ive used DSLR in the past but dedicated cams performance is much better and easier to use filters.

DSLR and 585MC

[leaden pumice]

I’ve been debating if I should get a full spectrum t3i or a dedicated Astro camera. I do like the Astro camera picture more.

[grave marten]

I think just for ease of introducing filters alone, makes the case for dedicated astro cam. The 585 makes a compelling argument with its cost/performance ratio.

[leaden pumice]

I might end up getting it, might go for the pro to help with the hot temperatures in the desert

[grave marten]

Ive paired it with many pro models from the 294 to the 071 to 2600 and the 585 non pro. All produced good results. I have yet to see a comprehensive compare between the 585 pro and non pro. I'd like to see that tho!

[chilly ingot]

well even with sony starvis sensors. when they are warm, the noise is quite big

cooling is so good honestly

[leaden pumice]

I did get the rokinon for canon DSLR, would that still work the 585?

[chilly ingot]

canon EF mount, yes. Most adaptable for astro use

[grave marten]

Does noise matter that much when you swamp it with signal?

Still would like to see the comprehensive compare between the 585 pro and non pro

[chilly ingot]

this camera is at +17.5C and only 60s exposure (imx533). It has tens of times more thermal noise than a cooled camera doing a 5min exposure

[leaden pumice]

Alright! I’ll be getting the pro in a few weeks then! Thanks for the information you guys!!

[chilly ingot]

the dark current graph tells the rest of the story. every 5C it goes up by ten times

but the data still stacks fine. with signal there is a presentable image for sure

processing takes care of the rest. just depends how picky a person is.

[grave marten]

Yeah... All fine and dandy on paper and single exposures don't tell a whole story

[chilly ingot]

but cooling for sure is a god sent for long exposure narrowband

i myself is battling to get good signal from a more polluted area. i take all the gains

found a sub with same camera doing +6.5C. Same scope, same sub length. Alot less noise.

left +17.5C, Right +6.5C

[grave marten]

Still single subs which don't do much for me 🤷. Far from a comprehensive comparison. And I'm all for cooled cams. I'm just particularly interested in the 585 pro vs non pro.

[chilly ingot]

i found extra noise really problematic when resolving fainter stuff.

fast lens, high fullwell, lowest noise possible. Let there be dust

[grave marten]

Well be proud of your discovery sure. But I'm still just looking for the 585 pro vs non pro comparison.

[chilly ingot]

well go and find it then, its all in the spec sheet to calculate thermal noise for a comparison.

the imx sensor are like everything else when they are warm. really noisy

[small scaffold]

i need all nighter targets for this sundayy, with the samyang and unmodified cam

[dire flicker]

orion

[small scaffold]

except orion and andromeda please :C

[dire flicker]

M33

[grave marten]

Heart and Soul is rising pretty early. Nice wide FoV could be nice.

[leaden pumice]

Tested dithering last night, 120 second exposures, around 3 hours total, new dithering settings.

I noticed this weird cloud over the picture before stretching (after background extraction in autostretch). I have on M31 and M45, is this normal? I messed with the background extraction settings but nothing changed it. I originally placed the red boxes in the background but after so many tries I just generated them

[civic mirage]

Literally the only reason to not get cooling is budget limitations.

[grave marten]

so they tell us...🐑

[old goblet]

you can adjust the samples it generates with left and right click, just gotta make sure none of the samples are on stars or the target itself

[civic mirage]

The difference in dark current between cooled and non-cooled cmos sensors are not gonna be very far off from each other, except maybe early cmos chips.

If your not budget limited, it makes sense to get the most out of which ever sensor your going with.

[leaden pumice]

I did try that but it was still the same. Not really sure why but I don’t think it changes the results, especially if I add more data to it. I went back and re-processed it.

[old goblet]

can change smoothing amount

[chilly ingot]

no

Using player one graphs. Doing a 300s exposure with a IMX585 at -5C or +20C has a absolute massive difference

1.137e of total noise per pixel over 300s at -5C OR 36e at +20c

you can take darks, dither and stuff. but with the randomness of thermal noise you can only mitigate it

why even have it in the first place

best feature in a camera. Cooling

[civic mirage]

Ah I kind of said that wrong, I meant the difference between various recent cmos chip's performance when cooled isn't gonna be very different. A 585 is gonna benefit from cooling around the same as a 533 or 571.

There all the same architecture in a sense... Temp is going to have very similar effects to all of them. It's mostly dependent on how good the cooling is.

But yea I totally agree

[chilly ingot]

i usually just check what temp i need to hit for narrowband

cooling too much does almost nothing after a point

just drains my battery alot

with 533 and 571 cooling to -10c ur good for almost anything around 5 - 10min subs. good for 5min subs at -5c

But at warmer ambient temps i can run the cooler at higher power since the battery lasts longer.

@civic mirage cuiv has two videos on this. One with 294's where the uncooled just didnt resolve the faint stuff. Second vid is going over camera specs and he does all the math around astrocam graphs.

[civic mirage]

I'm the winter I kinda wanna try -20 c lmao

I'm wondering if my 1600mm doing 10 min subs would see a considerable benefit.

[chilly ingot]

probably yes.

571 at -10c has same dark current as 1600 at -20

[civic mirage]

dam lol

[open swift]

I thought it was a wilder diff

Like 5c on the 533/571 equaling the dark current from 1600mm at -20c

I think it was near positive 5c , but possibly -5c

[chilly ingot]

actually ur right. there was a extra zero in the 571 graph 😂

[crimson goblet]

Bruh I've ordered a Sony A roki and I got a Sony E

[crimson goblet]

Of course its a bad copy...

At f2.8 on a 585 sensor it's already bad and it doesnt get better at f3.5 or more

I'll send it back i guess

[gleaming flare]

Have you ruled out tilt/backfocus?

Actually those stars look really bloated

I'll agree

[crimson goblet]

Backfocus is good to around 0.5mm and i'm not sure there's no tilt at all but it looks consistent across my setups (directly mounted to the sony body or to an adapter to the uranus c) so I'll check again but I think it's just a bad copy

[crimson goblet]

Tbf my process is atrocious on this one (5 mins of exposure through some clouds so not easy lol)

[solid raptor]

Shouldn't Backfocus be accurate to at max 0,1 mm?

[crimson goblet]

Yes I will try again with a more precise adjustement

Tho it shouldn't be too bad for the sony camera

And it is

[verbal quail]

Am I gonna want to track with an EQ mount for the comet, or just take untracked photos with a regular tripod

[dire flicker]

TRACK

[gusty rock]

Shot some untracked for fun, hate the small star trails

[verbal quail]

Do I need to guide or just track siderially with a decent polar alignment?

[solid raptor]

Since you wanna do relatively short exposures, tracking should suffice but guiding doesnt harm

[verbal quail]

20-30s exposures at 135mm

[solid raptor]

Won't that burn you the comet out

[verbal quail]

What exposure time should I be using at 135mm