Re: [APML] New TAK image - Cats Paw Nebula

[Mark Bohrer <lurchl@ix.netcom.com>]

Monte:
You've shown me what's possible with the Tak FSQ-106N. I have this scope 
and Extender-Q on a GM8, and an M6 with 50mm Noctilux and 135mm APO-Telyt 
for piggyback and a Nikon F2 for prime-focus shooting. I only hope one day 
through practice to have sufficient skill to approach your shot in quality.

Corner darkening (sometimes called vignetting) was a problem with the Zeiss 
Hologon 15mm lens (and it's still a problem with my Voigtlander/Cosina 
12mm). Zeiss used to include a special filter with the Hologon that was 
progressively darker towards the middle of a circular central zone to 
reduce it. This cutoff/decrease of brightness at the edge of the field is 
similar to what you're experiencing with the 6x7 camera on the Tak. I've 
read in various places about applying a circular gradient in Photoslop to 
mitigate the effect, but haven't tried it myself.


>Having solved the file problem I am now in the game.
>
>Here is a Cats paw I did last week. E200 1 hr 6x7 on Tak fsq-106. Push 1 
>stop dev.
>
>I have only fiddled with it a little bit yet. It seems to be a rather red 
>scan. I am wondering if that area has a bit of  HII and it is fooling me 
>into thinking it is a colour balance problem.
>
>510kb file
>
><http://www.tradepart.com/techinfo/catspaw.jpg>http://www.tradepart.com/techinfo/catspaw.jpg
>
>Regards
>
>Monte

Mark Bohrer
www.kokophoto.com
Pro mountain bike racing on the web


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