Wide field-'False Cross' area of night sky.

[hotspur]

A couple of very basic images,from testing some new gear,a new equatorial mount,and a Canon 10-22 mm wide field lens,piggy backed on scope.(unguided)

Exposure is 4 1/2 minutes,the second image a crop of first.The seeing not so good (28th Feb Thursday night),the few previous nights were better.But sounds like the clouds are coming back,so I wanted to sort of test with this gear,while a had a chance.There is what looks like a red star near the Southern Cross,I am fairly sure its not noise,I checked the other images,and did a dark frame.If its not noise,may be Ron could let us know about it.

Some high cloud really picks up the light pollution from Brisbane 170 Km's away.
Thanks for looking.

Chris

[koputai]

Not bad Chris, I would never have thought about using the 10-22 as an astro lens!

What aperture did you use?

Cheers,
Jason.

[Octane]

I'm pretty certain the red thing is a hot pixel.

Nice field of view, actually. Nice and sharp, too.

H

[hotspur]

Thanks for your thoughts Jason and Humayan,yes the red thing may very likely be noise,I did not notice it on the other images I took that night,but does look like noise.I appreciate a master looking at my attempts and giving comment.

Yes,Jason-one of the 'main menu' reasons I bought the Canon 10-22 mm was to be used for wide field astro-photography,Some gentlemen here in QLD use this lens for such purposes and do very good wide field images-Tony Sumra the President of Astrofest took a lovely image with his copy that featured in 'Astronomy 2010',also a chap in the AAQ uses his copy for some really great Astro images,that have featured around the world.

I used AV of 5 for this image,not sure what I should be using for such images.I really wanted to do some basic testings of this gear (as the clouds have come back),and see how the mount tracked unguided-it was the third time I have used the new GPD2,and first for any sort of photography-no major star trails.

Thanks for looking-Chris

[alexch]

Nice result, Chris.

If I may share my experience here, with higher ISO setting and some post-processing you should be able to pick-up more nebulosity in the Milky Way and Magellanic clouds, especially on a tracking mount (I do all my wide-field shots on a fixed tripod).

I played with the levels in your images just to see if I could reveal some of the Milky Way. I attached edited versions, the mighty dark River is noticeable in the Milky Way and Eta Carina area stands out so do Magellanic clouds.

It's hard to work with highly compressed jpeg files and the result is awfully noisy but should be much more reasonable with the original files. The noise levels would go down further if you split your exposure in a few and then stack those together. I found stacking works well even on ultra wide-field images.

I hope you don't mind me playing with your images.

Cheers,
Alex

[hotspur]

Thanks Alex.

These results of yours are fantastic,considering you only had a basic low res jpeg to play with.I really appreciate your advice and words of encouragement.

I do plan to short exp and do stacking etc.and get the family to turn lights off in house!.I mainly wanted to test tracking and see what wide field looked like with this test.The fact that a experienced chap like yourself took the time to have a basic play with these images,tells me the set up has potential for some good images,thanks Alex.

Its a nice wide field at 10 mm,that bright star -top right hand side,is Achenar.

Cheers Chris