M51

[gritty stratus]

M51
Celestron C8
AVX Mount
SSAG
Celestron Reducer flattener
SVBONY SV605CC cooled camera
A few hours of 120s frames

I just started astrophotography about 2 months ago

[lunar copper]

thats nice act

I think u got walking noise?

yea u def do

[gritty stratus]

Thanks! Is that the sort of pattern in the noise? Any tips on getting rid of it?

[crisp comet]

Shoot flats

And darks

[gritty stratus]

Ok, I’ve done a few darks, but I’ve never shot flats. I use Nina, and see there is a flat wizard, I’ll try messing with that!

[crisp comet]

Definitely shoot flats. They remove vignetting and some noise

[gritty stratus]

I’ve heard of the “Tshirt” method, and using a sketch panel. Some also say to just point at a cloudless sky at dusk, which do you all use

[crisp comet]

I use a t-shirt and a flashlight but the best method is to use a sketch panel

[gritty stratus]

Thanks for the info. I’ll try some next time. And flats should be taken any time the optical train is changed?

[trail cypress]

Like your flats should be taken exactly as you taken your lights, don’t detach your camera or something before taking flats. Like I recommend taking the flats right after the lights, but just don’t do anything to the setup, leave it as is. The reason is that if you take out your camera you could change the location of dust spots on your sensor that flat frames are supposed to correct, which will result in…. Not proper correction.

[crisp comet]

Same with your darks. Maybe your biases but I don't rlly think that matters tbh

[tropic relic]

If you can figure out how to dither your images, I would do that. Basically averages out any pattern noise that your image could get. Increasing the signal to noise ratio.

[gritty stratus]

im definitly not ditheright now. i havent tried the nina sequence generator where i think i can automate that. shoud dithering be done every shot?

[tropic relic]

idealy yes, but your mount has to be very accurate to dither on every shot. The dithers need to take very little time to settle, the less accurate your mount mechanics the longer it takes to dither. but if you cant dither on every shot, dither every other especially if you are taking longer exposures. Its literally so good to dither.

[gritty stratus]

ok ill start with dither every shot, my exposures are typically between 60 and 240 seconds, and i think i can have the mount settle time so that it will wait after dither for 10-20 seconds before beginning exposure

i appreciate the feedback

[lunar copper]

no

DITHERING

dither or die

darks+dithering

whether that be manual or auto

[crisp comet]

That's true

Dither is better

[lunar copper]

darks wont help much

[crisp comet]

I still haven't been able to do it though

But whatever darks work fine ig