First attempt at M31

[SpookyKatt]

Hi all,

Well I've started trying to do a little imaging after seeing all the wonderful images done by SGL members and this was my first attempt that actually results in something other than star trails or a black sky.

Its a quick image of M31 from just a few unguided subs of 110 seconds using a Tal 200K and a focal reducer with some darks. I don't think I had the mount fully level and it was a little overloaded which I think was wasn't helping the tracking hence why I kept it below 2 minutes. I find that the processing is a bit of a black art I must admit I find, but will have to just keep practising.

Quite pleased with it as a first attempt, but have so much to learn. Any pointers are very welcome.

Kathleen

[gary1968]

Ah, so your delving into the dark arts Kat, lol....... A bit of vignetting going on in there, take some flats to get rid of that.

Its a good 1st image Kat, M31 is a tricky blighter.....

There seems to be a bit going on in the background, I will have a play l8r.

Keep 'em coming.

Gary

[gary1968]

I had a wee play Kat, there is some data in the background, I can see some dust lanes coming through. I cant get it any better than this as the core is so bright.....

Having said that, I am no expert, others might have better results than me, but I wouldn't mind a wee play with the subs as I dont think the clouds will ever part here again to let me out.....

Gary

[SpookyKatt]

Cheers for that Gary, yeah an over saturated core is what I keep getting but

saying that it was only a few subs and I mean a few. Its funny that the

picture on the camera looks better than what I've been able to achieve

but I was pleased to see something there.

I didn't crop the image and need to as when you adjust it to get more data

the effect of the focal reducer (I'm guessing) gets ever more noticeable.

Kathleen

[gary1968]

You shouldn't need to crop the image Kat, the effect you see is vignetting and, I believe, is caused bt the optical train not illuminating the chip fully, someone correct me if I am wrong here, :-)

Take some flats with the set up, scope/camera/reducer, exactly as it was for the subs, i.e. dont remove the camera or reducer until the flats have been taken.

To take flats, cover the front of the scope with something like a white T-shirt and point it at an evenly lit source, a nice blue sky for example. Set the camera to auto and fire of loads of 'flats' ( you are imaging the light path and any imperfections in the optical path) Add them to the mix in DSS and viola, vignetting 'should' be removed.

Hope that helps......

gary

[SpookyKatt]

Cheers Gary, thats great I'll give that a try and see what happens.

Kathleen

[Whippy]

It's a good start Kathleen, the 200K probably isn't the best scope to try to image with because it's slow and has a long focal length so it's a fairly steep learning curve you've got there!

Perhaps trying for something that's not so bright might even be a good idea, something like M33?

Tony..

[SpookyKatt]

Cheers for that Tony, yeah your probably right re a less bright

target. I wanted to try the Tal focal reducer to see what affect

it had on a big target which was why I tried M31. I'm not sure

how well it was sitting on axis as I took some quick lights as per Gary's

suggestion and re processed it to see how it would perform and when I

fool around with the curves there's still that odd vignetting which

makes me think it maybe wasn't sitting fully on axis or maybe I

just used it wrong.

Next night I will maybe try M33 as you suggest to see how it performs.

Cheers

Kathleen

[Parus major]

Very, very nice.

[SpookyKatt]

Cheers Parus, it wasn't bad for me and a just a few

subs. It kind of wets my appetite for another go

though, especially to try various adjustments to

the setup to make sure I've got it setup correctly.

Kathleen

[Parus major]

I'll look forward to seeing more. I'm hoping to do some imaging soon after I get my motor fitted, fingers crossed I measure up to yours.

[barkis]

You have detail in there Kath, unfortunately there is some vignetting, and this is resricted to the central areas. Core is too bright. Nevertheless, some dust lanes can be seen in the galaxy.

You need a faster imaging scope, or a focal reducer as suggested.

Ron.

[SpookyKatt]

Cheers Ron, yeah your certainly right about the core brightness

and vignetting. More practise needed I think .

Kathleen