The Swan in H-Alpha with a DSLR

[seeker372011]

Imaged on the 03/08/07 but only processed today.

an hour and twenty minutes (ten min subs) at ISO 800 with a 13nm Astronomik H-Alpha filter.
ED80
Canon 300D (modified)
CG5 Mount (auto-guided with PHD)

I don't think I got enough exposure- i actually collected nearly double the number of usable sub frames but had tracking difficulties which i believe are due to a failing power supply.

Comments and Suggestions welcome.

For a larger image go to http://www.flickr.com/photo_zoom.gne?id=1092674096&size=o

Clear Skies
Narayan.

[Radar]

That's a great image Narayan. You've captured the wispy parts well. I can see what you mean about tracking. I had a close look at that image and at first thought that it may have been slightly out of focus, but it looks more like minor drift during an exposure. I could be wrong on this though. The bright star on the left seems to have a faint ring around it, I imagine this is from drift?

Ray

[seeker372011]

The bright star on the left seems to have a faint ring around it, I imagine this is from drift?

Ray

I do struggle with halos around bright stars even with the H alpha filter..but you're right, focus looks like its a bit soft-though I used DSLR focus as always , but maybe the seeing contributed?

[Radar]

but maybe the seeing contributed?

If there is moisture in the atmosphere this can cause halo's to. I have had this problem on film.

Ray

[seeker372011]

I had a go at sharpening the image ..reprocessed-now I wonder if I have sharpened it too much :hmm: :hmm: :hmm:

http://www.flickr.com/photo_zoom.gne?id=1103686280&size=o

gosh its hard to get it right sometimes
Narayan

[BitsyLon]

Hiya Narayan :)

Great Image! I think I like the sharpened version more - I think you'll find it more usefull, especially if you are planning on adding some color to it later :eartoear:

Cheers,

Lon

[Radar]

I had a go at sharpening the image ..reprocessed-now I wonder if I have sharpened it too

Sometimes we are to harsh on our results. Only astrophotographers can see an astro image's faults. To the lay person this image is nothing short of stunning. Sometimes when I'm processing an image and I'm not getting what I want I have to remind myself that only a few people on the planet will be able to see the flaws.

Narayan do you also shoot on SII and OIII?

Ray

[seeker372011]

Narayan do you also shoot on SII and OIII?

Ray

Ray

I do shoot in OIII but I don't own a SII filter.

However I did shoot the Swan the following Saturday in RGB (the Canon is after all a single shot colour camera) and I combined the two images using the following workflow:

1-Combine the H alpha image with the Red channel of the RGB image (80%)
2-create a new RGB image -using merge channels in photoshop
3-add the Halpha to the combined RGB image -screen mode at 30%

This is a Rob Gendler process I think (from memory)
so this is what I wound up with

for a larger image

http://www.flickr.com/photo_zoom.gne?id=1115970998&size=o

Thanks for looking, comments and criticism welcome

Narayan