Re: [APML] Another processing challenge!

[Philip Perkins <philip@astrocruise.com>]

Monte,

That's a good high quality image.  There is no processing challenge with 
your image, it just needs scanning again with the colour balance adjusted 
for correct black level.  The green and blue are approximately correct but 
the red is way too high.  Also keep an eye on the scanner contrast setting 
to ensure that the stars are not white-saturated - it is better to build 
contrast by combining two or more high quality scans with a lower contrast 
setting than to set the contrast overly high on a single scan.

BTW there is no need ever to post a 9Mb TIF - even if you wanted to make an 
exquisite 30"x40" print of that image a 10/12 JPEG will do the job 
wonderfully.  For the purposes of a processing challenge, even an 8/12 JPEG 
is probably over the top.  In regards to 'powerful men' with broadband, 
it's worth bearing in mind that light pollution is also likely to be 
'powerful' in areas where broadband is available, so I'm pleased that you 
spared a thought for those in 'astronomically friendly' parts! <g>  The 
500K JPEG is more than enough to determine the nature of the image in 
detail- thanks for posting it.

--Philip

At 07:25 19/07/02 +1000, you wrote:
>After a few frustrating months I have a processing challenge. It was taken 
>with a TAK FSQ-106 and 6x7 Pentax. E200 60mins push 1 stop. It is of 
>I.4628 in Scorpius RA 16H 46' -41. There are a few more I will post in the 
>next days.
>
>There are two versions a quick 500kb jpeg for bandwidth challenged people
>
> 
><http://www.tradepart.com/techinfo/i4628.jpg>http://www.tradepart.com/techinfo/i4628.jpg
>
>and more powerful men will feel right at home with a 9Mb TIF
>
><http://www.tradepart.com/techinfo/i4628.tif>http://www.tradepart.com/techinfo/i4628.tif
>
>Any thoughts on the image would be appreciated. I have made no changes to 
>the file it is a raw as they come.
>
>Regards
>
>
>Monte

Philip Perkins - philip@astrocruise.com
Wiltshire UK & Luberon France
Astrocruise - http://www.astrocruise.com


--  APML Archives at <http://astro.umsystem.edu/apml/>  ---
             Unsubscribe at <majordomo@seds.org>