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Murray@uptowngallery.org
Joined: 03 Apr 2002 Posts: 164 Location: Holland MI
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Posted: Tue Nov 14, 2006 5:05 pm Post subject: |
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Does anyone know the max. f.l. one can get to focus on a 4x5 Pacemaker CG or SG? I've never measured it and don't have it where I am right now (but I have a question right now!)
I know the minimum f.l. is different on CG vs. due to the fp shutter.
Thanks
_________________ Murray |
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Doug Kerr
Joined: 10 Jul 2006 Posts: 177 Location: Dallas, Texas, USA
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Posted: Tue Nov 14, 2006 5:33 pm Post subject: |
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Hi, Murray,
The maximum distance from a likely location of the second principal point of the lens to the film plane on a Pacemaker Crown Graphic is about 12.75" (this is with the front edge of teh front standard carriage just flush with the tips of the fully-extended bed track).
I believe that the focal plane on a Speed Graphic is about 0.75" further back (owing to the presence of the FPS) than that of the CG and thus we might suspect that the maximum focal length for focus at infinity on a PSG would be about 13.50" (343 mm).
_________________ Best regards,
Doug |
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Dan Fromm
Joined: 14 May 2001 Posts: 2156 Location: New Jersey
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Posted: Tue Nov 14, 2006 8:27 pm Post subject: |
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On 2006-11-14 09:05, Murray@uptowngallery.org wrote:
Does anyone know the max. f.l. one can get to focus on a 4x5 Pacemaker CG or SG? I've never measured it and don't have it where I am right now (but I have a question right now!)
I know the minimum f.l. is different on CG vs. due to the fp shutter.
Thanks
| Murray, it depends a bit on the lens and how you set it up. The longest standard issue lens for 4x5 Graphics (with and without FPS) was the 15"/5.6 TeleOptar (also badged TeleRaptar). Remember that telephoto lenses have shorter back focus than normal lenses of the same focal length. Also remember that the rear node of a most, not all, lenses of normal construction is very near the diaphragm. So a longer lens will work front-mounted than in shutter, and you can put a lens in barrel on an extension tube ...
And how close you need to focus makes a difference too.
Good luck, have fun,
Dan |
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Murray@uptowngallery.org
Joined: 03 Apr 2002 Posts: 164 Location: Holland MI
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Posted: Tue Nov 14, 2006 8:32 pm Post subject: |
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OK, good info.
I was wondering if I'd need a lens box instead of a lens board. (15" nominal (376 mm engraved).
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45PSS
Joined: 28 Sep 2001 Posts: 4081 Location: Mid Peninsula, Ca.
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Posted: Tue Nov 14, 2006 8:34 pm Post subject: |
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According to Graflex Model History, on this site, the Crown max extension is 12 1/2 inches and the Speed is 12 3/4 inches. A 12" (305mm) anyone's will close focus to 25 feet on a Pacemaker Speed.
_________________ The best camera ever made is the one that YOU enjoy using and produces the image quality that satifies YOU. |
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