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NGC7000 Pelican nebula 76x30s ISO 1600

Started by Daniel, Jul 09, 2008, 14:00:50

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Daniel

Hi all, just a quick image I got last night, only had about an hour on it as was working late, but for the first time I also took some darks (17 in all) haven't bothered taking them before as thought I'd wait till I got my lightbox sorted for flats too, but thought I'd try it out anyway.

Big improvement! before I've been unable to stretch the images too far before they became grainy, but I was able to push this much further.

Anyway, next time im definetly going to use a field flattenner too, Im loving the little 80ED for these big fields but hating the amount of coma around the edges



Oh, by the way, there's little in the way of proccessing on this image, just the usual colour stretching and black leveling, but apart from that nothing else!

going to really push it when I get home from work tonight

JohnP

Daniel, Where do you live? How did you manage to image last night....! I'm sure it was 'lashing' with rain all night in Bromley...?

Nice image by the way & yes you really need to sort out your flattener - I had the same problem when I first got my WOZS66 - I used to have to crop about 70% of the frame. It's still not perfect with the flattener but at least I can use something like about 80% or so...

Look forward to seeing some more - John

RobertM

Nice shot Duncan, I had a bit of clear weather to but it was 50/50 going out - I decided on the 50% staying in.

Do you stretch each colour seperately ? I've only stretched all the RGB components together and adjusted the dark point, though having seen Marks IRIS presentation I will try some non linear stretching and manipulation using that.  I generally import FITS images to PS with log stretch to bring out detail so it would be nice to be able to do that to to the DSLR images to.

PS. What manufacturers disk drives do you buy ?  I think I may invest in some shares ;)

Carole

QuoteDaniel, Where do you live? How did you manage to image last night....!
I was going to say the same thing, I wasnot aware there were any blue skies around here last night.

Nice image BTW.

Carole

Fay

Daniel, you must have been the only one with clear skies!!!!

What were your imaging details & what field flattener do you hope to use?

Fay
It is healthier to be mutton dressed as lamb, than mutton dressed as mutton!

Fay

It is healthier to be mutton dressed as lamb, than mutton dressed as mutton!

Daniel

Thanks guy's, yes it was a bit of a close call, I literally didn't set up till about 12:30am but had just enough time to get this Im in woolwich just up the road from Mac.

I seperately colour stretch my images since the levels are almost always seperated from eachother (particularly the red now I've got a modded camera)

I spoke to simon at widescreen center today and apparently I should be able to use my meade field flattener on the 80ED so shall try that next time I get out (which may be some time by the looks of it)


Fay

What program did you stack them in Daniel?

I am not sure if what you are saying about the levels is what I was getting wrong, until John put me right.
If you go into PhotoShop, levels & click on the middle eye dropper, click on clear bit of image background, the 3 colour peaks all go into one. The image will them not be pink but grey.

As I say, not sure if this is what you mean.

Fay
It is healthier to be mutton dressed as lamb, than mutton dressed as mutton!

Daniel

#8
I stacked in DSS using median kappa sigma clipping on light and dark frames.

I usually manually set my RGB levels one by one since (up until i got the camera modded) I've had to squeeze every last shred of Ha data out of the images I've captured

Oh, by the way I've just done a re-process of it while on the way back from work, not sure what I prefer this one has more detail but might be over processed, what do you guys think?


Fay

Well, I don't think it is overdone. There is a lot more detail come out.

I am interested to see how your flattener works on the next image, but it is a really good image Daniel.
I am at the moment, trying to sort out a suitable focal reducer/ flattener to suit my ED80/ eos setup, because of my corners.
It is healthier to be mutton dressed as lamb, than mutton dressed as mutton!

Daniel

Im picking up an adapter so i can use my Meade SCT focal reducer / flattener tommorrow so next night out, I'll test it and post the results

Mike

We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

Rocket Pooch

ok nice image, I have to try my ED80 EOS again I'm sure I did not get field curvature?




Daniel

The camera I took this on was the EOS 40D, not sure if the chip size would make much difference to the amount of field curvature you'd see (i guess it's mainly vignetting it affects) But i know the 40D's chip is pretty big.

Rocket Pooch

Hi,

Yes it would, how big is it compared to the EOS300D, I know with the 300D you can use an AP reducer and not add any curvature.

Have a look here http://www.cloudynights.com/item.php?item_id=1468

Chris