Re: [APML]: Balance

[Len Bright <bright@infomagic.com>]

byen@ix.netcom.com wrote:
> 
>  I noticed you went 15 min with 135mm/2.8 lens on hypered Fuji SHG400.
> Was it stopped down, the image looks pretty well corrected in corners.
> (What lens brand is it?)  I get a pretty good exposed neg 12-15 min
> @f2.8 on unhypered Fuji SHG400.
> 
>  I was tempted to use it myself on evening of Oct.10, but opted for the
> Fuji SG800+ (which has good blue response & finer grain).  Unhypered,
> the 800 supposedly is 1 stop faster than the SHG 400 (say 5-7 min
> @f2.8).  So, you shouldn't be unhappy with no more SHG400 - just use 800
> (as long as the comet shows a lot of bluish ion tail).  I was impressed
> with the 800's dynamic range (the SHG400 is known for this) on my 300mm
> FL Schmidt Camera shot (Oct 10).  I got inner nucleus & curved jets,
> like on your narrow angle shot.

The 135mm lens I use is a Nikkor f/2 which I stopped down to f/2.8. I
was 
uncertain whether or not I would need to stop down 1 more stop since I
have
never used this lens for astrophotography but it does a pretty good job
at
f/2.8 near the corners of the field. 
I am happy to hear about SG800+ since my supply of SG400 just ran out.
Thanks,
-Len
-- 
 


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       -Len Bright          *                
       bright@infomagic.com             *                              
       http://www.infomagic.com/~bright     *
       Peaks Observatory                   
       Flagstaff, AZ, USA                **                            
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