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Re: [APML] Another tech pan Q: (developing, etc.)



 
----- Original Message -----
Sent: Wednesday, May 09, 2001 9:55 PM
Subject: Re: [APML] Another tech pan Q: (developing, etc.)

So anyways, Did I fix too long now possibly?
 
A 7 or 8 minute fix will not cause any problems.  (Assuming the temp was in limits)
 
 
Whats this bright ...dark spot in the middle of my frame?
 
What lens were you using and at what f/stop?  I think you mentioned wide angle.  If so, the acceptance angle of the H-Alpha filter may be smaller than the width of the field, causing vignetting.  Also, a wide open f/stop will cause a hot spot in the center of the field and more vignetting at the edge.
 
Hi Rob,
 
I was using a 105mm f/2.5 and it was wide open for both shots. My first shot was for 30 mins., but I forgot to set the focus right.
The 2nd shot was focused right, but was cut short at 23 mins, because my guidestar hid behind a tree...murphy missed me(g).
My unfocused shot of 30 mins has the least vignette, while my focused shot of 23 has the most.
About how far should I stop down? Will this in any way effect my calibration mark and how it focuses?
 
Thanks,
Brian
 
Robert Reeves                      reeves10@swbell.net
520 Rittiman Rd.                   www.robertreeves.com
San Antonio, Texas 78209    210-828-9036
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