Wednesday, September 24, 2008

Milkyway Center



Camera: 350D modified
Lens: Canon 135 F2 Wide open, on ball head Manfrotto 308RC
Mount: EM11USD3 manual guide, GA4
Guidescope: FS60C
Exposure: 4 pane mosaic, each pane ISO400 4min x 3

There is a little catch in this lens, which made me fail in my imaging in the later XinJiang trip. The key to focus the 135 lens is, despite traditional wisdom, not trying to cease the moment of the smallest chromatic abberration. So on the contrary, when the lens is focused, there is a very tight red/magneta halo around the stars. Also, it is CRITICAL to focus this lens properly, otherwise the whole texture of the image would fall apart, no matter how small the out-focused distance is.

With the above image (also the RHO complex one), I eliminated the red halo with post processing in Photoshop.

Again, I was so surprised by the outcome of the image. this image was not very well preliminary planned before the trip; it just happened when I try to get a shot of M8M20 and I realized I could try to do such a mosaic. Another surprise came to the quality of the image despite the 12min exposure of each frame. That may have to do with the low temperature on the mountain top, and also the large aperture of the lens.

I'm ow so desperate to get the films scanned... but I still don't have time yet.

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