Ultra widefield H-alpha image

[riklaunim]

4 x 10 min, Astronomik 12 nm H-alpha, DSI-III Pro

The "imaging setup":

Astrometry on flickr says:

Field size :11.67 x 8.80 degrees

Your field contains:

The star 4Sgr

The star 7Sgr

The star 9Sgr

The star 11Sgr

The star μSgr

The star 14Sgr

The star 15Sgr

The star 16Sgr

The star 21Sgr

NGC 6469

NGC 6494 / M 23

NGC 6514 / M 20 / Trifid nebula

NGC 6526

NGC 6523 / Hourglass nebula / Lagoon nebula / M 8

NGC 6531 / M 21

NGC 6530

NGC 6546

NGC 6568

IC 4701

NGC 6595

NGC 6618 / M 17 / Omega nebula

NGC 6626 / M 28

IC 4715

[fatwoul]

Any chance of another image of the setup? The camera bit at the top is dark and difficult to make out. Cheers.

[swag72]

I have looked at this a couple of times and can't help but think that it's a tad off focus. Nothing seems particularly sharp in it. I'm also quite surprised that in 10 min subs with a CCD camera more data hasn't been captured. Have you tried longer subs?

[riklaunim]

It's a DSI III Pro, Astronomik H-a 12nm filter and 35 mm focal length 1:3.5 Paragon lens.

It may be a little out of focus, or it just can be blurred by seeing and some clouds (weather wasn't that good). The area is very very low over horizon and I had problems avoiding trees + and even with the H-a filter I got a big gradient (big city). Chec the bin2 shot (with tree): DSI IIII Pro and a small lens | Flickr - Photo Sharing! - with the gradient.

Lens image: http://oi51.tinypic.com/33f6p6o.jpg (with QHY5)