Ritchey–Chrétien enjoyers thread

[digital nexus]

well without it i cant use my reducer

so

[harsh matrix]

Right...

[digital nexus]

Didn’t we have this discussion already

I literally can’t attach my focuser without either the tilt plate, or one of the m90 extensions. And if I use my 25mm m90 extension, it’s too much and I can’t reach focus

[harsh matrix]

Yes

I remember

[harsh matrix]

What if you rack the focuser out to where it would reach focus without the tilt adapter and put the focuser on then?

[digital nexus]

it doesn’t reach focus at all

It was really close with the 25mm extension but it racked all the way in

[harsh matrix]

Craaaaaaaap

[digital nexus]

Yea

[harsh matrix]

https://www.esa.int/Science_Exploration/Space_Science/Hubble_shows_baby_galaxy_is_not_so_young_after_all

@frosty shard

[slate falcon]

guyysss do i get IC10 with the HeII filterr

[harsh matrix]

I doubt you will get anything

[slate falcon]

soo you saying i shoud

[slate falcon]

do you know anything about how you do this?

to get a slice of an image

[harsh matrix]

No

[tight lodge]

Long slit spectroscopy?

[slate falcon]

yea

i wanna try it at some point

i dont know how easy it would be though

[tight lodge]

It's fun and painful at the same time. Imagine stopping your f5 scope down to f20

[slate falcon]

have you done anything with it?

[tight lodge]

Well, not really. The slit can be tricky to calculate. And the difraction grating is also gonna cost you a big bag of chicken bones😅

[slate falcon]

[tight lodge]

1,2,3 or 4?

I need quick answer!

[harsh matrix]

yo momma

im feeling 2 atm

[slate falcon]

4!!!

[tight lodge]

Bruh💀

[tight lodge]

I'm thinking 1 or 2 as well

[tight lodge]

How many lines/mm?

[slate falcon]

honestly dont know

[slate falcon]

look how it has 2 reflections, idk how i can angle it

[tight lodge]

Should I get 5h L and 3h or RGB or straight 8h of L?

[desert locust]

all lum]

[harsh matrix]

Do you have multiple clear nights lined up?

[tight lodge]

Nope

Just this one

[harsh matrix]

Id set up 2 parts to your imaging sequence, do like 10 or 20 loops of RGB, and then have it swap to lum for the remainder of the night.

[tight lodge]

Thats kinda how I set it up

[harsh matrix]

Yeah do that

At the very least you get some color with lum instead of being left with an incomplete dataset.

[tight lodge]

Monochrome images can be complete datasets.

[slate falcon]

THIS

[tight lodge]

@candid flame show the guys how a mono image can be a complete image

[slate falcon]

i think amma shoot another northern fake target

northern lagoon time

[harsh matrix]

I know except ive had so may monochrome images lately that im sick of it.

[slate falcon]

oh wait no im doing bubble

[tight lodge]

At this moment I'm a bit desperate to image anything

[candid flame]

the latest addition :)

but it's probably a deadly sin to share that in a thread called #1326833769495269376 lmfao

[frosty shard]

REEEEEEEEEEEEEEEEEEEEEEEEEEE RASA USER GET OUT

I feel legally obligated to gatekeep sorry

[frosty shard]

I feel like we should actually have more threads for telescopes tbh, like you should be running the f/3 or faster club

[slate falcon]

i should make a flat reducer to reduce my coma corrector

make my scope f3 at the cost of a corrected field size

[frosty shard]

What scope and cam do you have again?

[slate falcon]

6" f5 noot and a 585

cc brings it down to f4.5

i can either get a 0.75x cc or do something silly with lenses

[frosty shard]

What kind of Newt? And is it a 0.9x coma corrector?

(Mainly just need to know the central obstruction size or percentage)

[slate falcon]

its the skywatcher 150p and yea its a 0.9x cc

the corrector is only meant to go to f3.5 ish though

[frosty shard]

I mainly wanted to do a comparison of everyone's rigs' pixel etendue

[slate falcon]

[desert locust]

do mine

also what does etendue mean

[frosty shard]

What's your optical train and camera?

[desert locust]

6" f/5, 2.9 752 mm

[frosty shard]

So the idea is, f/ratio isn't actually speed for a few reasons: besides the presence of a central obstruction, your rig's effective speed also depends on the size of your pixels

The correct comparison of "speed" is the product of your light collecting area with your angular pixel scale

That is etendue

It also factors in the size of your rig as well

Larger rigs will be subject to less shot noise because they collect more light simply due to their larger physical area

[slate falcon]

i need a 1 meter f2 scope

[frosty shard]

Corrected pixel etendue calculations for the rigs of frequenters here, as well as some well-known telescopes:

My and @crisp flower's RC8/IMX533M at native focal length: 5750 mm² arcsec²
@digital nexus's and @tall summit's RC6 with Apertura 0.67x reducer/IMX533M: 9617 mm² arcsec²
@desert locust's 6" f/5 Newtonian/IMX585: 10189 mm² arcsec²
@tight lodge' Sky-Watcher 130PDS/IMX585: 10480 mm² arcsec²
@slate falcon's 6" f/5 Newtonian with 0.9x coma corrector/IMX585: 12578 mm² arcsec²
Hubble Space Telescope/WFC3: 12842 mm² arcsec²
@harsh matrix's RC8 reduced to 0.65x/ATR2600M: 13611 mm² arcsec²
JWST/NIRCam: 20279 mm² arcsec²
@tall summit's new Sharpstar 13028HNT-AL/ASI585MC: 26883 mm² arcsec²
@candid flame's 11" RASA/ASI6200MM: 89291 mm² arcsec²

actually, now that I think about it, the better unit might actually be mm² rad², because you can omit a conversion factor for that

[candid flame]

is arcsec² well defined as a unit of solid angle in general?

i thought we needed steradians for that

[frosty shard]

Yeah, we use it as part of surface brightness

[candid flame]

but i mean 0.5" x 2" != 1" x 1"

[desert locust]

what about my future 8" f/3.7 with a 585

[candid flame]

ofc it is mathematically, but in terms of the solid angle that would equate to

and ofc it basically is true for small angles like an arcsec, but technically

[frosty shard]

Btw, if anyone wants to calculate it, the formula for etendue is
π * (r_primary_mm)^2 - (r_CO_mm)^2) * (RAD_TO_ARCSEC / 1000 * pixel_pitch_um / focal_length_mm)^2
with RAD_TO_ARCSEC = 206.26480624709637

[frosty shard]

What's the CO?

[desert locust]

co?

[slate falcon]

fentral obfruxtuon

[desert locust]

oh, obsruction

[frosty shard]

central obstruction size (either linear, area, %linear, or %area works)

[desert locust]

73mm

or 36%

[frosty shard]

17873 mm² arcsec²

[slate falcon]

what would mine be if i had the 294c sensor?

4.63um pixels

[frosty shard]

You can square any angular unit, it's just that steradians have the nice property of corresponding with the proportionality constant 4π in the surface area of a sphere

I guess you could derive a more sensible solid angle unit from the spherical circle with a radius of 1 arcsecond

[frosty shard]

32063 mm² arcsec²

[desert locust]

what about mine?

[candid flame]

hmm, maybe my intuition is just off

[frosty shard]

Sorry @desert locust pinged the wrong person:
17873 mm² arcsec²

[candid flame]

anyways why pixel-etendue and not full sensor etendue lol

[slate falcon]

thats not bad tbh

[desert locust]

is lower or higher better

[frosty shard]

That's also a useful measure, but if you're thinking in terms of "speed", pixel etendue is what you want to compare, since that doesn't depend on sensor size

Sensor etendue tells you more about how much total information you gather at once

[desert locust]

and one more, what if it was f/3 with the same obstruction

[slate falcon]

is it oer pickle?

[versed roost]

no, two patches with the same angle^2 size dont necessarily have the same solid angle

[candid flame]

i mean i would argue that's what actually matters for a nice image, but that might be a longer discussion lol

[slate falcon]

https://youtu.be/k7ocAzSFJLU

!!!

i think they made the mininoot usable

[frosty shard]

Higher is better, and the comparison is linear, so just divide the pixel etendues of two rigs to get a sense of their speeds

[frosty shard]

27187 mm² arcsec²

[slate falcon]

it has an R&P focuser???

[candid flame]

wait a minute i just realized this is just pixel area divided by effective F ratio

[slate falcon]

jesus

[candid flame]

now it makes sense for smol brain lmfao

[frosty shard]

Would this invalidate how I'm calculating pixel etendue?

[desert locust]

gyatt damn

[versed roost]

i dont think so because the FOVs here are pretty small, they are approximately the same

[candid flame]

wait this is exactly what i was saying

maybe i'm not smol brain after all idk

[desert locust]

is this a bad sensor amp glow aside https://player-one-astronomy.com/product/artemis-m-pro-imx492-usb3-0-mono-cooled-camera/

[frosty shard]

I'm trying to wrap my head around the correct approach to this, even if the corrections are practically nothing

[candid flame]

now that i think about it, i think it depends on how you measure your angles

[desert locust]

assuming bin2

[candid flame]

because euler angles are not the way to measure the side lengths of the "square"

[frosty shard]

I think it will also depend on how the celestial sphere is projected onto a flat plane. For a pinhole camera it'll be a gnomonic/rectilinear projection

[candid flame]

yeah it somehow makes the focal length not constant across the frame, or however you want to think about it

[slate falcon]

after the change my image sharpness has gone up so much

lets appreciate how silly my rig looks

[frosty shard]

the calculation I'm doing is strictly on-axis

[candid flame]

yeah so you also don't have to worry about projections

[frosty shard]

there will be some falloff due to this effect, but I think vignetting and aberrations will be far more significant

[candid flame]

anyways... full sensor etendue

[slate falcon]

browi can you cook an onion with your scope?

caramelise them

make caramelised onions

[candid flame]

maybe if i point it at the sun

surely nothing bad would happen

[slate falcon]

nothing bad ever happens!

[frosty shard]

I think you can just multiply the pixel etendue by your pixel count

[candid flame]

oh yeah ofc

[slate falcon]

my etendue is now 0

[frosty shard]

Which gets you 6.643212863670641e12 mm² arcsec², but I think that says it's time to pick new units

[slate falcon]

i accidentally unpluged my cam

[frosty shard]

512594 mm² deg²

[candid flame]

6.6km²arcsec²

km in the unit is somehow actually hilarious

[frosty shard]

Meanwhile I'm at a measly 9502 mm² deg²

[candid flame]

rasa vs RC moment

[tight lodge]

I can't believe you forgot about me

Absolutely devastated

[frosty shard]

I mean you're also working with a full frame sensor and I'm working with an IMX533

[candid flame]

yeah that's true, but partly because the rasa has such a large image circle

[frosty shard]

Wait oops. What's your rig specs again (everything in your image train)? I assume you're still on a 585

[frosty shard]

In theory I could go up to full frame with a flattener

[desert locust]

meet in the middle with an f/3.7 newt

[tight lodge]

5" reflector, 650mm focal length and yes, IMX585

[frosty shard]

Got a coma corrector in there?

And what's your CO size or %

[tight lodge]

It's a newtonian... yes I do 😅

[frosty shard]

is the focal length 650 with the corrector in? (and if not, what's the scale factor?)

[tight lodge]

26% linear, 8% by area

[desert locust]

I lowk have to get the highspeed filters because f/3.7 is too much bandpass shift

[candid flame]

huh

[desert locust]

also I might go f/3

[candid flame]

26%² = 6.76%

[frosty shard]

@tight lodge you've been added

[tight lodge]

Plus the mirror mask?

[frosty shard]

I assume you're masking the outer regions of the primary? How much of it?

[tight lodge]

Idk, I usually add an extra to the values. Even if that results in a number that is worse than the actual one

[tight lodge]

Uuuh, 650mm that's what ASTAP gives me😅

[frosty shard]

If you're masking 1.5 mm of radius then that would drop you down to 9968 mm² arcsec²

But there's more factors at play I haven't included, like transmission

also note that pixel etendue doesn't incorporate anything about resolution either

[slate falcon]

@candid flame have you shot N-Lagoon?

this guy

[candid flame]

nop

[slate falcon]

awh :c

do you plan on ever?

[candid flame]

maybe the entire area

[slate falcon]

[desert locust]

I think I shot that

[slate falcon]

[desert locust]

it was when I was untracked and the data was bad so I threw it out

[slate falcon]

yk its bad when some of my best photos are still my untracked ones

[frosty flicker]

🥀

[slate falcon]

i am gaining again thogh

sadr :3

[desert locust]

my best photo is my trapezium and i think we know why

[slate falcon]

trapezium?

[desert locust]

its gonna be a while before I surpass that

[slate falcon]

show

it

[slate falcon]

ohh

yk its bad when thats your best 😭

[desert locust]

vro

[slate falcon]

(simplicity of the target not the quality)

(and overshotness of the target)

its kinda overdone

[slate falcon]

paint you need to get a 3d image of the dumbell nebula

doing the guessing

[desert locust]

I gotta get cocoon data tho

[slate falcon]

truee

i love the cocoon because of how stupid it looks

[desert locust]

I have a dillema with my filters

[slate falcon]

all of them all at once

[desert locust]

when I go mono i need to buy non highspeed filters because f/5, but when I get my 8" i need to get highspeed because f/3.7 which is annoying

[slate falcon]

hear me out, get wide filters like 6.5nm

[desert locust]

but I really want 3nm

[slate falcon]

honestly just wait

or get the filters but dont use them

until you get the scope

[desert locust]

but then I cant shoot nb

[slate falcon]

paint wadaya think of this thing

this image apparently has an arrow in it

[desert locust]

cool but idk what that is

[slate falcon]

northern triffid

[desert locust]

cool

[slate falcon]

i like the blue streaks in it

do you like the blue streaks

(in the nebula not the walking noise!!!!)

[slate falcon]

are you gunna shoot all the abbel pne's

i honestly feel like i should

because it could be fun

[desert locust]

nah, but I could help you if you want, would be a cool project

some of the dimmer ones would be very hard tho

[slate falcon]

i dont know when i will start

[slate falcon]

and the smaller ones

[desert locust]

weve already shot 2

[slate falcon]

because they the stupid lemon looking things

[desert locust]

3

abell 81, 13, whatever the lemon one is

[slate falcon]

whats 81?

[slate falcon]

that lil guy!!!

[desert locust]

52 is cool

so is 78

[slate falcon]

61 looks like 39 but dead

i will make a chart that i can put all my abells into

maybe just pne's in general

the question is

1.4 hours of HeII vs 30 mins of Ha

who will have the better snr

(most likely Ha)

ITS NOT EVEN CLOSE

[stiff mason]

What brand and please do no say ZWO

[harsh matrix]

585MC Pro is a ZWO name so it is ZWO

[stiff mason]

But nowhere near the same pixel per arcsecond

[stiff mason]

Ik i was double checking cause sometimes people say that but they actually mean another camera

[harsh matrix]

https://tenor.com/view/hehe-gif-1840159130613519810

[waxen mountain]

That looks really good

What did you use for the flats ?

and you fixed the light leaks on your decoupler when i rembemer correctly ?

[crisp flower]

Just ordered some screws to replace the Locking- and collimation screws of the primary to i can collimate it properly

[waxen mountain]

Here 2h on the Wal Galaxy

[crisp flower]

Looking gooood

Better than Mine atm

Im gonna restart this one once i have the primary recollimated tho

[waxen mountain]

Seeing wasn't good?

[waxen mountain]

Thanks

[crisp flower]

Nah collimation was the problem

Or rather is

[waxen mountain]

Yeee A little bit off

[crisp flower]

Mine has blurx applied to it Looks better than it wouldve

[waxen mountain]

I only used wavelets transformation

[crisp flower]

Niiice

[waxen mountain]

and 200% Bilinear Resampling

No Drizzel

[waxen mountain]

Nice setup

what did you use to add the mini pc/router to the radgoll

[digital nexus]

3m velcro

i bought a big roll of it

[waxen mountain]

Oh

[digital nexus]

you need to take off the polar scope adapter thing

but it was easy

[waxen mountain]

I installed my PC like this

[digital nexus]

ohh you used the screw from the polar adapter thing

i didnt have anything like that so i just used velcro

its stable enough and will come off if i need to move it'

[waxen mountain]

Yeee

works quite well

If I have a 3D printer then I might print a platform to put things better there

I like this position for the pc on the mount

[tight lodge]

I need more data

[waxen mountain]

Wow Looking good

[haughty steppe]

Yeah, the little beelink adapter is nice

[frosty shard]

How much do you have?

[tight lodge]

5h of luminance and less than 2 of RGB😭

[harsh matrix]

This is my main worry.

[harsh matrix]

does there appear to be walking noise?

i think there's a little bit just barely seeping in now

i either need to dither every exposure or dither by more pixels

the weird thing is i see it worst on the right side, and not so much on the left side

when i shoot more lum, i can probably eradicate that by adding some better dithered data

i think there is

[harsh matrix]

unless it's IFN, which is unlikely

[harsh matrix]

yeah

i big dummy

thought i could get away with dithering every 2 3 minute subs but i cant

or i need to push the thing way farther when i make it dither

[waxen mountain]

Maybe both

[harsh matrix]

im thinking both

i wont be using the edges of the frame anyway

[waxen mountain]

Here 46 minutes on m63

[slate falcon]

i see it streaking

[waxen mountain]

Yeee

[harsh matrix]

yeah

[waxen mountain]

But I also edited it

[harsh matrix]

i can fix it with some more data, dithered a lot better

also it was pretty windy that night so it's possibly whatever dithering was done wasn't done well, like the mount was being pushed back to where it was before the dither

it was bad enough that i tossed a good 20 or so subs

[digital nexus]

has anyone used an OCAL before

[harsh matrix]

no but ive collimated using my guide cam and all sky lens

[digital nexus]

huh thats possible?

[harsh matrix]

it works just as well and it is far cheaper

yes

my quattro has perfect collimation from me doing that

[digital nexus]

elaborate... i happen to have both of those things

[harsh matrix]

[digital nexus]

with an RC tho?

[harsh matrix]

it may or may not work with the RC

[waxen mountain]

I have

[harsh matrix]

generally everyone advises against collimating with OCAL or all sky lens on RC's because the primary and focuer are attached

[digital nexus]

you are the first and only person ive heard say that

[harsh matrix]

also the center spot on the secondary marks the mechanical center and not the optical center

[waxen mountain]

is probably the best solution if you don't want to or can't use stars

[harsh matrix]

so most likely you will not achieve good collimation doing that

[digital nexus]

then how tf am i supposed to align my focuser

[harsh matrix]

I say this because everyone who tries to bench collimate these things can't get it good enough to be usable so they all give up and sell the scope

[digital nexus]

people in my club use the OCAL just fine

sounds like a skill issue

[harsh matrix]

you dont lol

as long as the focuser isnt way out it wont matter much

[waxen mountain]

The primary is fixed on my CCT 🙏

[digital nexus]

well i cant use stars so im using the ocal

[harsh matrix]

for RC's?

[digital nexus]

yes

[harsh matrix]

i can understand it being a skill issue with a noot

[harsh matrix]

have they shown any of their results to you?

[digital nexus]

no but i know 2 people who use them for RCs

[slate falcon]

guyysss left or right

i figured out how to brighten certain areas :3

i also got a bit of the reflections off the dark neb bc continuum

[desert locust]

more int

[slate falcon]

bleh

[slate falcon]

i really should pump loads of int into it so i can get the hot af ifrared glow from the dark nebula

[desert locust]

or try some cool galaxy

[slate falcon]

the glow is so hawt

[desert locust]

I also know something else thats hot

[slate falcon]

galactic nuclei?

[desert locust]

nah, me

[slate falcon]

fales

[desert locust]

whale+hockey stick galaxy is hot too

might image that

[slate falcon]

oh yea btw i already have the dark structure but not enough into to bring it out yummy

[slate falcon]

!!

[desert locust]

its a cool galaxy group

[slate falcon]

is

[desert locust]

fov with starizona

[frosty shard]

I know the RC copypasta is about laser collimators, but it seems like the OCAL is going to suffer from the same problem - too dependent on mechanical properties of the scope to be reliable

[digital nexus]

the ocal isnt a laser

[frosty shard]

Yes. But it depends on mechanical alignment

[digital nexus]

I’m terrible with the star Collimation

I make an adjustment, the star jumps a billion light years away. And I can’t manually slew since it’s a harmonic.

It’ll take me an hour to find the star again

So frankly the OCAL is my only bet or I’m selling the rc6 for a newt

[slate falcon]

thats why you do it in a star field!!!

[digital nexus]

Then the stars are too small

[slate falcon]

do it in a bright cluster then!!!

[digital nexus]

Not to mention when I’m doing the star test the seeing is atrocious and it’s impossible to get a precise reading on Collimation

[frosty shard]

How are you adjusting the collimation screws? If you're using a screwdriver with an Allen head, I highly recommend an Allen key instead

[digital nexus]

im using a allen key

[tall summit]

with asiair at least, plate solving still works with a reasonably defocused stars, I just tell it to go back

ocal definitely should get you in a ballpark though

[crisp flower]

I am now hopefully prepared to Not lose this one in the Grass when im collimating the primary in half an hour

[digital nexus]

The plate solving I method doesn’t work great at high FLs, so combined with the defocused stars, there’s no chance

[harsh matrix]

@frosty shard

The artifact still remaining might be camera settings after all.

I'll give this a shot tonight.

Tomorrow night. 💀

The weather sucks tonight.

[harsh matrix]

@frosty shard also did the flexture test with the DSD OFP2

no dice

it's actually 1:1 between flats on the left and right side of the meridian

will try a difference between at park and at zenith next

this is a completely uniform gray image btw

i tried more contrast but there's no difference

uh oh

we have a difference

[slate falcon]

minispot

the yucky rings are kinda baad

[slate falcon]

will you ever be able to correct the rings?

[harsh matrix]

no idea

most likely not because the nature of the vignetting is mechanical and not optical

it's too aggressive and sudden

[slate falcon]

yea

have you ever thought about a model to correct it?

i could try make one

[harsh matrix]

No because I have no idea how to do something like that

If i could learn how, sure id do it in a heartbeat.

[slate falcon]

you could hand paint one

[harsh matrix]

Yeah

Has to be perfect though.

Okay big problem

https://cdn.discordapp.com/attachments/1128673711042592829/1485725131107205200/image.png?ex=69c2e8da&is=69c1975a&hm=4f8af9412adbafdbae935327026916362f7eb269ccc5d1c9dfa0c7c5ef71b66d&

Okay I need to rack everyone's brain

The parked flats differ from the right side and left side of pier flats

[slate falcon]

balck screen wuth blue line?

[harsh matrix]

Taking a difference between those results in a difference that looks like this

Taking a difference between those differences results in a completely uniform image, even with a pedestal added.

[crisp flower]

i think thats close enough

[harsh matrix]

Its a screenshot so I included the edge of the pix window by accident.

Ignore it.

[slate falcon]

aah

[slate falcon]

awh okayy

[harsh matrix]

The reason I took a difference between the differences is because if it was somebody's light causing it, the direction of the problem should have changed.

Why it cancels out perfectly makes 0 sense.

So think

Why in the hell is this possible?

[harsh matrix]

@tight lodge think

Think think think

Why

[tight lodge]

by any chance do you get any tilt from one side to the other side of the pier?

[tight lodge]

I'm thinking, maybe the whole rear end where the decoupler is attatced could flex slightly

i'm not sure how the mirror is held inside the tube

[slate falcon]

vel im trying to make one of some random screenshot you sent

issue is the bright ring

thats between 2 dark pats

[tight lodge]

Maybe, there's juuuuust a small amount of tilt. not enough to show in the light frames, but just enough to screw up the flats

[slate falcon]

beh

[harsh matrix]

https://deepspaceplace.com/gso8rcpointing.php

[harsh matrix]

Ive already suspected that which was the point of this test.

But I'm pretty sure it is showing up in the lights.

One set of flats should be enough to calibrate all of the lights if there wasnt some level of flex somewhere.

Also...

The mismatch in the center is always a left or right bias.

Never up or down.

[slate falcon]

@harsh matrix this is the best i could get with the png

[harsh matrix]

Whatever it is is definitely directional.

[slate falcon]

bwaa

[harsh matrix]

Not bad...

[tight lodge]

Can the mirror shift left and right in the cell?

[harsh matrix]

No

It can barely move as is.

[slate falcon]

yea

[harsh matrix]

Its supposed to be tight enough to have no play, but not so tight that you cant spin it.

I can spin it but it takes force.

A lot of force.

[tight lodge]

Yeah, it needs to float a bit

[harsh matrix]

The way this scope was when I got it is you couldn't move it at all.

[tight lodge]

Ok... then we exclude flop

[harsh matrix]

It was wayyyyyyyy too tight.

[slate falcon]

model looks like this

[harsh matrix]

Oooo interesting.

[slate falcon]

its missing the weird lump on the left because i accidentally deleted it

[harsh matrix]

Im going to the airport rn so when I get back home in an hour or so, do you want some raw data to experiment with?

[harsh matrix]

Yeah

It almost hurts my fingers to move.

[slate falcon]

no, this is how it looks accidentally made the subtract layer screen

[slate falcon]

ow

[harsh matrix]

How did you do that

Brushes?

[slate falcon]

a lotta stretches and a lotta gaussian blur

basically i removed the stars, clipped the whole image and then made 6 or so outlines of the gradient with a flat curve and pulling up the specific stuff i wanted

then some gaussian is applied

[tight lodge]

Then, my suspicion is something in the drawtube. Between the decoupler and camera
Do you have a dial indicator by any chance?

[slate falcon]

also this doesnt correct fully it just helps background extraction not go insane

[slate falcon]

how it looks before extraction

[slate falcon]

and then the after

[harsh matrix]

No

Maybe it is the cut off i have in the aperture of the decoupler.

It's there to catch any leaks that may get around the focuser drawtube, but i didnt use new strips of flocking material to secure it.

It's more than plausible that it could have come loose again.

[harsh matrix]

[harsh matrix]

Dang

[slate falcon]

im sure i could with tweaking

i would need a flat corrected stack though i think

[crisp flower]

How we Feeling about the Center of m94?

[harsh matrix]

@tight lodge I found a piece of flocking material, just the very corner of it, sticking off and over the very edge of the inside of the decoupler.

That was probably enough. 💀

I was able to pick the whole scope up by the focuser body and nothing moved, popped or snapped so... it's tight.

Very very tight.

The focuser CAN move laterally a small amount due to the beveled edge issue.

I was able to test it just now, but im not sure how much of an impact that will have without one more test.

[haughty steppe]

best night ever so far. Just wanna flex a lil somethin something rq. Livestack for 20x60s subs on M81. And the best guiding I have ever seen with my setup.

[frosty shard]

This is sicc I was thinking about imaging M94

[harsh matrix]

I brought the scope in to find whatever was moving, secured it in place, removed the flocking material that was in the way of the focuser, and still ended up with issues

however, the direction the rays of light come from is different every time

the neighbors had just about every light they could turn on, on

I think this may explain that

might need to repeat the test once they shut them off

[tight lodge]

Does the flat pannel move by any chance?

[harsh matrix]

no

ive tested that

had no difference between when i was putting pressure on it and when i wasnt

[tight lodge]

At this point nothing makes sense anymore 😭

[harsh matrix]

i know

this whole scope is far too sensitive to small light changes

honestly this effect looks like the same diffraction/ray scattering and reflections I saw in my subs from that airbnb i stayed at in mid december

this really could just be the neighbors lights because porchlights is what triggered what i mentioned before

these all differ significantly from last night's test too

bruhhhhhhh

[crisp flower]

I want to so badly but i cant Guide on it 🥲

[harsh matrix]

I have a theory

the flocking material actually mitigated any movement in the focuser

the second i removed that, it made the focuser move around easier

testing this right now by taking new flats now that the neighbors have all shut off their lights

[harsh matrix]

YUP

I THINK IM RIGHT

NO LIGHTS WERE SHINING ON THIS RIG

YET STILL HAVE A MISMATCH

left and right are different

zenith and park are different

that means no combination will work

this is the difference between the differences

again no lights were on out there

this should have been no problem

the accidental flocking material unironically helped

@tight lodge I found it i think, pretty darn sure

[tight lodge]

What is it?

[harsh matrix]

After repeating the same results i went out and checked the tightness of EVERYTHING.

Started man handling the camera

Put force up and down, left and right, and noticed excessive movement up and down.

Some left and right as well.

The drawtube is moving.

sounds like new focuser time

i didnt see the focuser body moving

it's possible it was

but the drawtube definitely was

now to see if i can prove it in results

the neighbor's lights were an issue

they caused an incredibly minor difference, but did not affect the central ring

both of these images are differences from the right side and left side of the pier with and without the neighbor's lights on

the only difference is some light rays from their porch lights

there's no difference in the center, my point of interest

this might be my smoking gun

at park, once again, light rays from their porch are the difference

and at zenith

moral of the story here is, the neighbors lights are a problem, they will give me bad flats with this flat panel, except that's not the primary cause of my problems here

it is the focuser moving around.

[tight lodge]

So something was moving as I suspected

[harsh matrix]

yes

as ive been confident of now too

[tight lodge]

Doesn't your focuser have some kind of tension adjustments?

[harsh matrix]

yes afaik

i dont know how well that will work

[tight lodge]

Worth a shot until you get a sturdier focuser

[harsh matrix]

im concerned about the body too

i had that piece of flocking material jammed between the decoupler and beveled edge of the body by accident which seems to have helped unironically

[frosty shard]

Finally got enough O-III data for a barely acceptable HOO image lmao

this is just stretched

[slate falcon]

[frosty shard]

HaRGBOIII preview

Man the O-III is really needed for the IRG image

[slate falcon]

blu

[frosty shard]

IHO preview

[tight lodge]

Ok... this has potential

[slate falcon]

yummy

[tight lodge]

Only if it wasn't green enough to reverse the global warming 💀

[digital nexus]

Whyyy

[quartz meadow]

those outer regions are really interesting

[tight lodge]

Astro tax

[silver ibex]

What the actual f

Literally a piece of aluminium 😭

[quartz meadow]

Another interesting target is NGC 3718. could be a interesting target for you @tight lodge

[tall summit]

I gotta say, I feel like I can collimate anything after my RC:) I was able to have a first light with f2.8 Sharpstar just after cheshire collimation

30sec sub with crap guiding

little tweaking on the actual star should bring it home

[tight lodge]

Smol but interesting

[quartz meadow]

You ideally wanna get like over 5hrs minimum to get those 2 arms

[tight lodge]

Brother, by the next new moon I'll be happy if I get 5h of night at all😭

[slate falcon]

same

[frosty shard]

@quartz meadow I have seen the tidal tails of NGC 3718 visually in my RC

[quartz meadow]

thats crazy

[frosty shard]

I was absolutely not expecting them to be visible but they are

[quartz meadow]

also that galaxy group down there is pretty neat

[slate falcon]

do you think my 6 incher will make them visible

or too smoll?

[quartz meadow]

visual?

[slate falcon]

bisual

[frosty shard]

It might be possible - the real constraint on seeing them is dark skies (I was in Bortle 3)

and it was directly overhead

[slate falcon]

im just below bortle 4 at zenith

[frosty shard]

It might be doable. Don't use too much power

That was last year, but I think I was using my 21 mm eyepiece, so 70x, and importantly, 2.6 mm of exit pupil

Those kinds of details do not benefit from higher magnification

You probably want to use at least 2 mm of exit pupil

[tight lodge]

Ye, he does this thing where he looks trough the telescope

[frosty shard]

You should try it sometime

[tight lodge]

Impossible

[frosty shard]

Over 1,000 people have tried it with my scope at this point

[tight lodge]

I converted my OTA into an astrograph😅

[slate falcon]

ill use my fancy flat field eyepeice

ive only used it 3 times

i gotta put it to use!!

maybe i will try the pacman nebula

[frosty shard]

Okay that one is super tricky unless you have a photographic H-beta filter (like the Baader ones)

Even a 12 nm filter does not cut it

[slate falcon]

darn :(

all i got is a uhc

its also low in like the b7 zone, i just checked

[slate falcon]

i think N-Triffid would go hard visually

[frosty shard]

You might find this to be useful: https://www.prairieastronomyclub.org/filter-performance-comparisons-for-some-common-nebulae/

I thought the northern Trifid was in it but it's not sadly

[slate falcon]

gah

its one of the suber bright targets too!!

[frosty shard]

The results may be different if you're using filters with narrower photogrpahic bandpasses btw

[slate falcon]

is a 7nm quadband too far?

has hbeta halpha oiii and sii

[frosty shard]

Which filter exactly?
I find it's better to have a bandpass that's too narrow than one too wide; despite what a lot of visual observers think the narrower O-III filters are very good despite dropping 25% of the signal

[slate falcon]

buh

amma go with a mid range quadband then

a mid range quadband would go hard as luminance data

[frosty shard]

The 7 nm filter would probably work better on tougher targets

Like the Veil when that's up

[slate falcon]

im not a visual sorta person tbh

[frosty shard]

https://tenor.com/view/jaw-drop-mask-shocked-wow-mouth-open-gif-16995665

Me when I saw the Veil Nebula in a 16" Dobsonian with a 7 nm dual narrowband

(and everyone else at the star party)

[runic violet]

Depends on your darkness of sky

ofc

[harsh matrix]

@tight lodge I tried the idea you and Benny had, tensioning the rack some more, made no difference.

I did find it was extremely loose and the focuser wanted to slip in general, but tensioning the rack still made no impact.

The drawtube moves a lot.

New focuser time.

[tight lodge]

https://tenor.com/view/wallet-gif-25866507

[tight lodge]

Isn't it an RnP focuser?

[harsh matrix]

Yes

You can still adjust the tension

[tight lodge]

I was expecting to be sturdier

[tight lodge]

@silver ibex recently got a focuser that actually might be worth every penny

Is one of em fancy EAFs from Prima Luce Labs I think

And in the future I might invest in ESATTO 2"

[harsh matrix]

Me too

Which it is if you pressure the drawtube directly

You cant make it move

But with my big and heavy imaging train?

If you use that entire thing as a lever arm, like how gravity will act on it? It moves quite a bit.

Im actually surprised there's that much room for play in there even with the linear bearing on top.

[tight lodge]

For some reason my focuser is sturdier than the tube rings in my case😂

[harsh matrix]

Oh an Esatto?

I think that would be fun and cool

It would definitely fix everything.

But.

[tight lodge]

Yep, he got the 3" for like 600$ or something

[harsh matrix]

I don't have over 700 USD to spend on one right now.

[harsh matrix]

Bro what

He stole it.

[tight lodge]

For real

[harsh matrix]

Luckily I did happen to get the extra day of work i asked for

Which was today

So I get a massive paycheck next week, and a full paycheck from last week despite having most of the week off because of PTO.

I can compensate a little, AND I can sell the rack and pinion to make some of that back.

[tight lodge]

What focuser you're going for?

[harsh matrix]

Baader Diamond Steeltrack

mostly because it has an adapter I know will work and everyone who has one says they have no give

[tight lodge]

I cross my fingers that will finally bring you back in business

[harsh matrix]

yeah

[tight lodge]

We really need you back in business. This server kinda forgot what a sharp image looks like

[harsh matrix]

@frosty shard

this upgrade aint so upgrade

for an imaging train of my bulk anyway

[harsh matrix]

baader diamond steeltrack is ordered

got some adapters too

[harsh matrix]

I believe it will be low enough profile to thread the reducer on directly

[silver ibex]

I might downgrade to the 2" though. I realised that the 2" is going to be far easier to use with the scope that I want

[harsh matrix]

i would have liked to put that money into the 3 nm Sii filter I'm missing but it is what it is

that filter wont be much of any good if i dont fix the focuser flop

[silver ibex]

That's also a good one afaik

[harsh matrix]

it sounds like the perfect focuser

lol

no light leaks

rock solid

could probably sit on your imaging train and it wont sag

[silver ibex]

Maybe the FT is better lol, just $$$

[silver ibex]

This thing has 8kg of payload btw

[harsh matrix]

only?

[silver ibex]

It's a lot, I couldn't get an imaging train to be 8kg if I wanted to

[harsh matrix]

oh apertura doesnt list a payload limit on the listing for the focuser i have

red flag

that's probably why i have issues ngl

[harsh matrix]

okay that's probably true lmao

im not being fair

[harsh matrix]

okay the Diamond Steeltrack is on par

not exactly the same

but close

my imaging train is probably 5 or 6 pounds

it's not light

but not excessively heavy either

[silver ibex]

Ah yeah I can change the preload too. Can probably push it to 10kg if someone wanted to

[harsh matrix]

okay

so we'll see how this thing does

I'm excited

I don't feel bad about the purchase yet

[silver ibex]

I think mine is slightly lighter, but similar

[silver ibex]

I think it's going to be good, I've heard good things

[harsh matrix]

yeah I think it'll be good too

im going to have to start selling old gear again

😂

i do think this will fix every problem that remains

unironically

and I think that when it does, I will have a rig that I trust for the next 2+ years

I'm genuinely hyped

ngl i kind of want to wrap the RC cause i messed up the clear coat on the carbon on the upper right side of the scope 😭

[silver ibex]

I didn't really follow the entire debugging process, I just saw a wall of text from you every couple of days 😭

[harsh matrix]

it's good you didnt follow

the majority of everything i tried was immediately in the garbage

pointless

useless

a lot of effort for nothing

very nearly sold the scope until I was finally able to isolate issues, and diagnose them separately

it wasnt even until last week when i was able to separate this focuser issue from the decoupler leaking light

the focuser problem was so bad that i mixed the light leak problem in with the focuser problem even though they were not the same thing at all

I thought the tube was at fault for all of it

this experience has taught me a very valuable lesson, I learned a lot, and this is the sort of reason why I have the amount of patience that I do

[silver ibex]

So at the end it's was just a bad focuser?

You did flock a shit ton of stuff too though

[harsh matrix]

yup

[harsh matrix]

exactly

everything I did only eliminated possible causes until the only thing left to check was the focuser

not just the focuser, but the build of the focuser

the build of the focuser isn't rock solid enough, at least for the size of imaging train I am using

to add insult to injury, the focuser being an inherently GSO design means it was flawed from the start

GSO makes okay focusers

but not ones that I'd say are worth imaging with.

if you want to upgrade, do it right

[silver ibex]

Yeah, shitty focusers seem to be the manufacturers' favourite way to save money

[harsh matrix]

and shitty focusers disguised as a good focuser is the manufacturers' favorite way to make money

[silver ibex]

Pretty much, although I think that GSO RCs are fairly priced. I would love an RC but it's hard to find a medium-high end manufacturer, it's either GSO or straight up PlaneWave 😭

[harsh matrix]

yes

I think that's an issue too

I would love to fix it personally but I am not in a position to start a new company

[silver ibex]

The easiest thing would be to keep using GSO mirrors as they seem Good Enough™ and just overhaul the mechanics completely

[harsh matrix]

yup

do what the i saw on facebook did

take the mirrors out

design a completely new tube

problem solved

[silver ibex]

That does it

[silver ibex]

So other people got the same issue?

[harsh matrix]

yes

you can see it everywhere

theyre most often using the stock focuser

like Limepie in here is

@slate falcon so the entire drawtube was shifting

that means the edges of my frame were not aligning

which is probably why I have that vignetting that NEVER corrects

it might correct mostly or entirely with a new focuser.

[tight lodge]

If that's the case, then I'm in danger again

[harsh matrix]

not only in danger

but in danger of getting absolutely destroyed come summer time

because my seeing will be busted

[tight lodge]

Wait until I get my fat 10"

[slate falcon]

😭

[tidal hearth]

On the 150i??

[tight lodge]

Ye

[tidal hearth]

https://tenor.com/view/thicc-boi-he-gif-19550103

[tight lodge]

For a fact I know that the 150i I up for the task. That mofo almost bent the tube rings. A 10" is nothing for it

[tidal hearth]

https://tenor.com/view/i-see-really-now-i-know-nod-1k-gif-11865986451428314791

[silver ibex]

It's more about wind tbh

For example I know that my mount can do 12" easily, wind is a bit rough though

[tight lodge]

I learned the weather patterns. Usually I don't even bother to image if earlier that day was cloudy

[frosty shard]

Another target I should consider

[quartz meadow]

draco triplet is a great choice

[digital nexus]

@harsh matrix so i got my focuser on without the tilt plate. I just racked it out more. So it won’t be able to rack all the way in, unfortunately. Il have to be careful with my EAF

Hopeful I can reach focus

[quartz meadow]

fingers crossed

[digital nexus]

And I’m gonna collimate it with the ocal tomorrow

[tight lodge]

Any triplet but Leo triplet is a great triplet

[quartz meadow]

I mean the Hamburger is kind of interesting because of the jet tbf

[tight lodge]

How I could frame it

How I will frame it

[quartz meadow]

mosaicing would be mandatory if i get the scope i want to have

[tight lodge]

Naah, I won't mosaic it. I'd rather spend extra time on one region and do it good

I don't care about the other two galaxies

[tight lodge]

I mean, just wait until the feed in #1127675764356173885 gets filled with only Leo Triplet

You will start to hate it as well😂

[quartz meadow]

oh i have started already 😂

[haughty steppe]

Oh, you got the expensive one

[frosty shard]

What's the rig you want?

Mosaics are fun to process tbh

[slate falcon]

meowsaics are the greatest

[harsh matrix]

good luck

[quartz meadow]

soo the plan is that I'll get a 10" newt, EQ6-R pro and 533 mono cam or I could strap on my 6d Mk II for full frame and nicer sampling?

[silver ibex]

Good luck finding a proper CC for full frame

You could go 8", the improvement in stability is going to be noticeable imo, at F/5 you have good sampling

[tight lodge]

There you go... that's why I hate FF cameras. The sensor is amazing, yes... but good luck getting a telescope that can correctly project on that sensor😭

[silver ibex]

You have good sampling with the 533 I mean

[silver ibex]

I would go full frame but my wallet simply dislikes the idea

[tight lodge]

APS-C it is then

[quartz meadow]

0.77 over 0.64"/px doesnt sound like much of a difference to me

but the stability thing is a good point

[silver ibex]

You could also go 10" F/4 and get the same focal length, if you are willing to suffer with the collimation

The difference between 0.77 and 0.64 is significant imo, at 0.64 you are not oversampled only if you get 2" seeing

[quartz meadow]

I was looking at a 10" F/5 well technically 4.8 the other day

[silver ibex]

Is that the juicy CT10 from OOUK?

[quartz meadow]

No, its a old skywatcher 10" that has been serving in a local observatory

[digital nexus]

help

[digital nexus]

@frosty shard maybe you can help me

So I collimated, and then rotated the ocal using my focuser’s rotator, and boom instantly the black area inside the red circle was moving all over

what do I do

[harsh matrix]

That's the focuser being mechanically misaligned with the optics. You can't truly fix it without decoupling.

[tall summit]

Maybe tilt plate?

[harsh matrix]

If you align with the tilt plate and then rotate the focuser, it's going to go out again.

The trick is to keep the focuser fixed and align everything then.

Don't rotate the focuser.

[digital nexus]

So I can’t rotate my camera then? wtf

[tight lodge]

You can rotate the camera, but not the focuser

[digital nexus]

And my rotator is on the focuser so

[tight lodge]

So you can loosen the camera and rotate it like that

[digital nexus]

What

My imaging train doesn’t do that

The rotator is on the focuser, and that moves the entire focuser

[tight lodge]

How is your camera attached to the telescope?

[digital nexus]

m48 pretty sure

[harsh matrix]

Or you can rotate your camera

You just have to recollimate for whatever rotation you want to use.

Or adjust the tilt

Pick your poison.

[tight lodge]

That's what I'm saying!

Or you don't rotate

[digital nexus]

The entire imaging train is screwed in, where is there to rotate the camera

[harsh matrix]

then there's the possibility that like the CYCK focuser on my Quattro, the rotator on your focuser has introduced tilt and that's what triggered the misalignment

so many possibilities

[tight lodge]

Well... I'm glad that I rotate my camera manually like a peasant

Or sometimes I don't and I shoot in equatorial mode

Fine example of not bothering with camera rotation

Perfect framing

[harsh matrix]

The issue is that when you rotate the focuser, you will create a misalignment between the camera and the secondary mirror

If you set the tilt for the focuser using the tilt plate, you undo whatever tilt adjustment you made for the focuser by rotating it.

Then you add on a misalignment with the secondary mirror because that will go out too, it creates a huge headache.

It sounds like it is going to be an unavoidable one for you.

I have a baader click lock for my current focuser which lets me avoid this headache for now.

It might be a different story once my Baader Steeltrack arrives as I intend to thread my imaging train on directly.

There are no steeltrack compatible click locks available right now.

[tight lodge]

I think I'm the one with allegedly the worst focuser and yet the most reliable one😂

[harsh matrix]

a bunch of people in the Nate decoupler thread have an RC like mine

plain carbon tube with no branding

[slate falcon]

you have a " " rc thats kinda cool

[quartz meadow]

thats really sexy

[tight lodge]

The best looking ones ngl. No branding, nothing

[harsh matrix]

Welp

Im working more hours than I bargained for next week

Maybe I get the Sii filter with next week's paycheck

[digital nexus]

My job fired me

[slate falcon]

@tight lodge amma try 10 min subs again

ive aligned my gs perfectly

[stiff mason]

why

[tight lodge]

Did you caused a lot of damage atleast?

[slate falcon]

ice in the fryer

sounds so fun

[digital nexus]

no.

[digital nexus]

they fired me cause so they can’t exploit anymore

[slate falcon]

grr

be more exploitable

[slate falcon]

ayy 10 min sub focus / seeing limited!

ig i gotta try 30 mins!

[harsh matrix]

Ive been doing 1300s exposures with my quattro

Got pin point stars most every night.

Doesn't work too well on the grass.

[slate falcon]

[harsh matrix]

That's unironically what makes it trail at all

[slate falcon]

yeaa ive had that issue

grass randomly decides it wants to compress a bit more

[harsh matrix]

It's surprisingly variable.

[slate falcon]

verybibl

if the wind causes trailing in this 30 min sub i may cry

[tight lodge]

That's why I put my body weight on the tripod before setting up

[slate falcon]

i just setup on concrete

[desert locust]

I have stupid EPDM

[slate falcon]

wat!

i dont speak shorted ed

whats an epdm?

300s lest to see horrendousness

[desert locust]

Ethylene Propylene Diene Monomer

its rubber

[slate falcon]

ahhh

[desert locust]

big problem is the cg shift while tracking messes up my pa

might put some wood under my tripod to make it better

[slate falcon]

[desert locust]

its pretty easly fixable

[desert locust]

gonna order the nexus rn

[slate falcon]

yipee

i wanna get one

[desert locust]

get an f/4 and reduce to f/3

[slate falcon]

tha plan

quattro modded into an f3

[desert locust]

alert, mystery plant also sprouting(idk what it is, I think its either tomato or cantelope)

[slate falcon]

plan (plant)

[tall summit]

Sorry to hear that man

[digital nexus]

im not

they gave me 5 hours every 2 weeks lmaoo

[tall summit]

What do you do professionally?

[digital nexus]

well im not even "fired" but a silently fired

[digital nexus]

cashier

and im student teaching which is a 40 hr per week internship

so i dont even want to work

[tall summit]

@digital nexus maybe bite the bullet and get this Apertura focuser? You'll be compatible with everything, have rotation etc. These come stock on Carbonstars, I have zero complains on mine. https://www.highpointscientific.com/apertura-eaf-ready-rack-pinion-linear-rail-focuser-6-8in-rc-and-cassegrain-telescopes?utm_campaign=&utm_content=&utm_source=google&utm_medium=cpc&utm_term=APT-LRP2-RC&utm_source=google&utm_medium=cpc&utm_campaign=17934693297&utm_content=139942520099&utm_term=&gad_source=1&gad_campaignid=17934693297&gbraid=0AAAAAD-khUYUVIYuJqRZD-X7gnfiYgjRb&gclid=CjwKCAjw-J3OBhBuEiwAwqZ_hzujmZcbsgjFw7EKkb8sOo0vUkI8Na0FH5f4yJlaUbO075EuAYWJNhoCC1oQAvD_BwE

[digital nexus]

id rather sell the rc6 and buy a newt then put anymore money into this thing

[tall summit]

Sucks that its not working out

[digital nexus]

i dont see how anyone can recommend an RC

[digital nexus]

im giving up

this is the best i can do

those spider veins are just not gonna align

[tall summit]

I certainly had a few nights of desparation with it. It looks pretty good though on the collimation, you should be within just a minor primary tweak (if any) to center a defocused donut

[slate falcon]

ltitlitlt?

[digital nexus]

thoughts?

i cant get the veins aligned

[tall summit]

Dont worry about it

[haughty steppe]

the veins are a rotation thing. Whats it matter

[tall summit]

Seriously

This looks as good as bench collimation can be

[digital nexus]

It’s as good as a Collimation il get. I’m not gonna try and mess with it on a star

Of course clouds will ruin my imaging session

[slate falcon]

thats good.

they all look aligned

[tall summit]

I have an opening till 1-2am

Planing to star collimate my new newt

@digital nexus whats the first target?

[digital nexus]

unfortunately not m100

Me and super are doing m100 as a project collaboration, but it won’t rise before clouds arrive

So I’m probably gonna do M81

[tall summit]

You have no reducer right? And what sensor?

[digital nexus]

Maybe M66-65

Little close to the moon though

[digital nexus]

I’m using the reducer 0.67. And a 533

[tall summit]

Nice, fairly zoomed in

[candid flame]

RC + reducer

[desert locust]

newt+ reducer

[candid flame]

RASA

[desert locust]

poor mans apsc

[slate falcon]

this fuckin thing

only a 27% loss of light

its f1.8~ if you account for co

[desert locust]

poor mans rase

[quartz meadow]

how's the spot diagram?

[candid flame]

please tell me you meant to spell rasa

[desert locust]

yea

[slate falcon]

doesnt quite compete with asskar off axis, on axis it is better aaand f5 or whatever vs f1.5 is a humongous difference

[slate falcon]

(mine is on the right)

[slate falcon]

also, no the spots are not triangle!!!

they are more rounded off

they are actually more like askars

[harsh matrix]

i already dont recommend a 6

and the reason youre frustrated is the same reason everyone else who bench collimated their RC gave up

bench collimating these isn't possible without a decoupled primary mirror and focuser

and tbh, i dont even think they should be bench collimated under any circumstance

[digital nexus]

If I have to collimate using a star I am selling it

It’s not worth the effort

[harsh matrix]

you cant get the necessary precision because GSO's mechanics suck

[harsh matrix]

how would you know if you've only used it once?

[digital nexus]

I’ve tried to collimate twice with stars

I’m not doing it again