M31 - Help processing?

[TerraC]

Please could anyone with some processing skills help me get anything out of this M31 data?  Not sure if it's terrible data, my terrible processing skills or a combination of both to be honest.  

I can see something is there.  I'm not expecting miracles but can anything be extracted or saved from this?  ISO 400 - 67x 60sec subs - 30x darks - 30x flats - 30x bias Stacked with DSS.    I've tried to process with photoshop and Startools but I just end up in a horrible over exposed mess.  Am I doing something wrong or peeing in the wind?  Could anyone help or offer any advice? 

 

 

M31-1.TIF

[almcl]

Here you go, processed in StarTools 1.8.518.

Not sure if it's what you were after, nor why there's no colour? But you have some detail in the dust lanes and some of the outlying nebulosity.  The focus is possibly a bit soft, but nothing desperate.

I did have to crop quite a bit, and you might want to revisit your calibration frames, particularly the flats, to see if they can be improved to help with vignetting, but that's way better than my early attempts at M31, so well done!

[Adreneline]

I agree with all the points raised by @almcl especially re. flats.

I put your tif file into PixInsight and did a rough and ready STF stretch which revealed the uneven background - was there any high cloud around maybe?

I then used lots of incremental stretches in PI and cropped the image to reveal this. There is colour there but it's difficult to pull it out for some reason.

HTH

Adrian

[TerraC]

Thanks guys. Already better than i've managed to pull out. 

Had a few clouds earlier on but I went through and discarded around 15 spoiled frames.  Looking at the others they all seem fairly consistant. 

I wonder if there may be an issue with the DSLR i'm using or the sensor needs a clean.  Seem to get this uneven issue with 2 scopes now. It's a 2nd hand Canon 550d un-modified.  

I think first port of call will be to shoot some new calibration frames to see if I have them ok.  

 

[ONIKKINEN]

Hmm, im not so sure the flats would be 100% to blame on the gradients, i get gradients like these imaging at the edge of an intense lightdome where one side of the image is much brighter than the other. What quality of skies was this shot from?

Colour is incredibly difficult to pull out for some reason, something must have gone wrong during stacking or capture. Maybe try with the 32-bit option in DSS if you were bitrate limited? (doubt it but worth a shot).

[alacant]

Hi

Nice shot.

+1 @almclregarding flat frames. They can make or break an image. Or at the very least, make it easier to process.

There is also a corner gradient. Moon?

This is with StarTools' latest beta. Synthetic flats to the rescue!

 

 

Edited November 1, 2021 by alacant

[TerraC]

52 minutes ago, ONIKKINEN said:

 

Hmm, im not so sure the flats would be 100% to blame on the gradients, i get gradients like these imaging at the edge of an intense lightdome where one side of the image is much brighter than the other. What quality of skies was this shot from?

Colour is incredibly difficult to pull out for some reason, something must have gone wrong during stacking or capture. Maybe try with the 32-bit option in DSS if you were bitrate limited? (doubt it but worth a shot).

Thank you.   I'm in a Bortle 5 zone but M31 is looking towards a bit of light pollution Bortle 8 early doors.  

[TerraC]

34 minutes ago, alacant said:

Hi

Nice shot.

+1 @almclregarding flat frames. They can make or break an image. Or at the very least, make it easier to process.

There is also a corner gradient. Moon?

This is with StarTools' latest beta. Synthetic flats to the rescue!

 

 

Fantastic thank you.  More than I thought I would get from this.   

I think it's light pollution on the right side.   Andromeda is probably the wrong way for me to be honest.  To my east there is a city Bortle 8+    I'm probably better shooting to the West or North to get away from the pollution. 

I like the feel of Startools.  I think it's probably time to buy it and spend some time getting to know it a bit better to see what I can get out of it.  

 

[ONIKKINEN]

56 minutes ago, TerraC said:

I wonder if there may be an issue with the DSLR i'm using or the sensor needs a clean.  Seem to get this uneven issue with 2 scopes now. It's a 2nd hand Canon 550d un-modified.  

I never had colour issues with my 550D, even in horrible bortle 8 conditions. It was difficult to pull out but not impossible. Maybe try shooting 800ISO and 30s? According to some sources (like APT) 800 ISO is the ideal setting for the 550D.

Try in daylight and see if you get a good image, that should put the sensor issue to rest.

[bottletopburly]

23 minutes ago, TerraC said:

I like the feel of Startools. 

Excellent piece of software 👍