Another attempt

[gcflora]

One day I will get this right :) This is attempt #3 of the milky way

http://lh4.ggpht.com/_6vdPqp2Fxq4/SquMQNWIR2I/AAAAAAAAA1U/44CkDshyP_4/s720/SBRK-Stars-20090912.jpg

[Scoobs]

That is a very cool image.

[gcflora]

Thanks Stu :)

[NovaTJ]

Great shot! Care to let us know what settings you were using and the location you took the shot from?

[Jon Foster]

Ya, you keep trying. And we'll keep looking at your failed attempts! ;)

Jon.

[gcflora]

Thanks all.

Settings:
5D2 and 17-40 lens. f5.6, ISO 1600, 20 x 30 second shots + 5 dark frames. Combined with DeepSkyStacker

[MintMark]

Hi gcflora, I think your image is fantastic. My attempt at something similar is in http://photography-on-the.net/forum/showthread.php?t=745400

Are your images taken from a fixed tripod? I get the same problem in the bottom left and top right corners. Do you have any idea what causes the distortion there? My current theory is that it is from the lens, but I'm not sure.

[Catanonia]

The problem might be the fact that the stars bottom left are closer to the horizon and so they move 'apperantly' more according to your view point than the stars above you.

This looks like star trailing in a widefield shot and you will get this on static mounts such as tripods if you shot over 30 or more seconds.

Just a guess, but looks like it to me.

[MintMark]

The problem might be the fact that the stars bottom left are closer to the horizon and so they move 'apperantly' more according to your view point than the stars above you.

This looks like star trailing in a widefield shot and you will get this on static mounts such as tripods if you shot over 30 or more seconds.

Just a guess, but looks like it to me.

Hi Catanonia, I thought the same too at first, but then I thought that every star in the image should be undergoing the same movement (rotation about one of the poles) and deep sky stacker should be able to deal with that.

Now you've got me thinking again and I'm wondering what happens if your image has a pole and the equator in it. Maybe it's a fundamental problem from projecting the spherical sky onto a flat sensor and you can't align all parts of the image when it includes a wide range of declination.

I think I need to think about it some more... but thanks for making me think :)