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Old 14-09-2007, 04:02 PM
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Geoff45 (Geoff)
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Geoff45 is offline
 
Join Date: Jul 2006
Location: Sydney
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Quote:
Originally Posted by avandonk View Post
I just purchased a Skywatcher 150mm F5 Achro. Here is a pic with the modded 100ED as a guidescope. The other picture is a single JPG straight from the 5DH. Exposure details 8 min at 1600ISO with Hutech focal reducer (0.85) and Astronomik HA filter. Focus could be better. The intention is to use it for narrowband data and just simply establish focus position for any filter and recombine the data with no chromatic aberration!

The Hutech FR is flattening the field very well. Will post a combined image when I get the data as it is a race against predicted rain.

I reckon this will work.

Bert
Certainly something worth trying. One thing occurs to me though. The focus points are slightly different for each colour, which means a slightly different focal length, which means the image scale will be slightly different for each colour. I wonder if this is a big enough effect to affect the final image?
Geoff
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