M31 - with almost 3 hours worth of data

[swag72]

I know that to the vets of astrophotography, 3 hours worth of data is probably quite tame! I managed to collect this over 3 nights. I would welcome any pointers and whether you think it's going to benefit from adding any more subs.

Taken with a 5D2 and a 300mm lens at f/4.5 on an HEQ5 Pro mount. This is a mixture of subs all taken at 1600 ISO. Stacked in DSS and processed in CS3.

Lights 17 x 120, 25 x 91, 45 x 60, 39 x 44, 11 x 30, 29 x 29, 13 x 14

Darks 19 x 120, 4 x 91, 38 x 60, 28 x 44, 8 x 30, 13 x 29

M31 Andromeda galaxy by swag72, on Flickr

This can be compared with this thread where I used less data - Is there a difference? I can't really see one!!

[tiwar]

A female imager!!! Being a visual lass (atm) this is very inspiring!!!

T x

[Beyond_Vision]

If you look at both images side by side you will see that the image with the larger amount of subframes is less noisey. This means that it can be stretched further. I think that you may still have some frames with thin cloud. It is also worth investigating taking flats. It's also worth taking a look at Pix-Insight and down loading the 60 day trial software. There is a tool called dynamic background extraction which will help to even out the background.

Regards

Kevin

[dlp]

I ran that through DBE in PI Sara - had to do it about 3 times to try and lose that funny area at the bottom left of the galaxy. Don't think that 'blemish' was there in your original so as Kevin says might be worth taking a detailed look at your subs before you stack them (I feel your pain!).

David

[steppenwolf]

I have compared the two in PS and there is much more fine detail in the dust lanes in the second image

[swag72]

Thanks for taking the time to look - Do you think it's worth adding more to this? I noticed that 'blemish' at the bottom, but couldn't get rid of it, however hard I tried! I'll look through the subs and see what may be causing it.

[jgs001]

Nice result Sara, as has been said more data = smoother image. Check the subs for the blemish but it's got a lot of detail there.

[swag72]

Thanks John - I've checked the subs and can't see what the blemish may be - nothing showing that I can see. So .................. Yet another stack ongoing!!!

[Psychobilly]

In my experience with DSLR's I doubled the total exposure time I spent on objects every year... in the fist year I just wanterd to grab some sort of image of all the "biggies"... grabing around 1 hour data before moving onto the next target...the data was stretched to breaking point...

It does become a case of diminshing returns depending on target 2-4 hours will give you something decent... as you have found...

When I was last imaging I would try to get around 6-8 hours on a target...

Billy...

[swag72]

Wow, so much more time to get then Billy!! I will persevere and add more, clouds permitting!!

[Psychobilly]

Grab as much data as you feel you need... but dont let other targets slip by...

This time of year weather permitting I would grab a few hours of the Rosette Nebula M42, M33 and M31 as they each became "optimally" placed for imaging...

Billy....

[swag72]

I am looking forward to trying a few more targets - M45 and M42 were my first 2 targets. I am lucky in that here in Spain I have quite good clear skies - Although not tonight.