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Eastern Veil - NGC 6992

Started by MarkS, Aug 30, 2009, 13:12:24

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MarkS


Last night I decided it was about time to get the ED80 out for a serious try - I wanted to get a test image before I purchase a field flattener for it for this Winter's forthcoming crop of widefield imaging.

This is 40 x 5 minutes, from my back garden, using the modified Canon EOS350D and a CLS filter.  I've scaled the image by 2/3 and cropped it to remove the elongated stars in the corners.

I'm quite pleased with the result.  I'd love to try it again from a dark site on a cold night.

Thumbnail below and full size here: http://gallery.orpington-astronomy.org.uk/albums/userpics/10046/eastveil290809.jpg

Mark



Daniel

That's a lovely image Mark, you can't beat the 80ED's for widefield shots. I'd be interested in hearing how you get on with the field flattener, i'd use my 80ED more if it wasn't for the terrible Coma it gives me!


Daniel
:O)

JohnP

Looks pretty good Mark - Well done - I didn't even know it was clear last night :-( John

MarkS

Quote from: Daniel
you can't beat the 80ED's for widefield shots.

Err  ...  you certainly can - it's called a C14 with hyperstar!!

Thanks for the comment.

Mark

Mac


RobertM

Nice one Mark, 3 1/2hours is a long stint but it's come out very well with all those subs.  Looks like you managed to get away without a pier flip!

MarkS

Quote from: RobertM
Looks like you managed to get away without a pier flip!

How do you know I did it without a pier flip?

Mark

The Thing

Very nice image.

How bad is an 80AT is compared to an 80ED? I would like to have a go at this one.

RobertM

QuoteHow do you know I did it without a pier flip?

That was just a guess based on a path of least resistance.  I reckoned you might get about 2hrs past the meridian so could get away without it - a pier flip is always a pain to realign back on target again. 

Interestingly the FOV you have there is about the same as I get wuth the SXV-H9 and the Sky90 at 405mm f/l.

It's certainly better than many I've seen with a cooled camera; did you use the CLS filter ?

Daniel

Quote from: MarkS on Aug 30, 2009, 16:09:36
Quote from: Daniel
you can't beat the 80ED's for widefield shots.

Err  ...  you certainly can - it's called a C14 with hyperstar!!

Thanks for the comment.

Mark

Hehehe, the C14, hyperstar combo actually doesn't give the huge fields of view the 80ED does, although the time you save on subs certainly makes mosaics more feasable!

MarkS

Quote from: Daniel
... the C14, hyperstar combo actually doesn't give the huge fields of view the 80ED does

I disagree.
C14 has aperture 355mm.  Hyperstar gives F/1.9 i.e. effective focal length of 675mm
Skywatcher ED80 has focal length of 600mm

The difference in field size is only marginal.

But the difference in imaging speed between F/1.9 and F/7.5 is stunning.

Mark

Daniel

Actually, your right, I looked back on my old 80ED North American Nebula images and realised the ones I took with the big field of view were focally reduced.

Daniel
:O)

Mike

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