| View previous topic :: View next topic | 
	
	
		| Author | Message | 
	
		| Murray@uptowngallery.org 
 
 
 Joined: 03 Apr 2002
 Posts: 164
 Location: Holland MI
 
 | 
			
				|  Posted: Tue Nov 14, 2006 5:05 pm    Post subject: |   |  
				| 
 |  
				| 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
 |  | 
	
		| Back to top |  | 
	
		|  | 
	
		| Doug Kerr 
 
 
 Joined: 10 Jul 2006
 Posts: 177
 Location: Dallas, Texas, USA
 
 | 
			
				|  Posted: Tue Nov 14, 2006 5:33 pm    Post subject: |   |  
				| 
 |  
				| 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
 |  | 
	
		| Back to top |  | 
	
		|  | 
	
		| Dan Fromm 
 
 
 Joined: 14 May 2001
 Posts: 2159
 Location: New Jersey
 
 | 
			
				|  Posted: Tue Nov 14, 2006 8:27 pm    Post subject: |   |  
				| 
 |  
				| 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 ... 	  | Quote: |  	  | 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
 
 
 | 
 
 And how close you need to focus makes a difference too.
 
 Good luck, have fun,
 
 Dan
 |  | 
	
		| Back to top |  | 
	
		|  | 
	
		| Murray@uptowngallery.org 
 
 
 Joined: 03 Apr 2002
 Posts: 164
 Location: Holland MI
 
 | 
			
				|  Posted: Tue Nov 14, 2006 8:32 pm    Post subject: |   |  
				| 
 |  
				| OK, good info. 
 I was wondering if I'd need a lens box instead of a lens board. (15" nominal (376 mm engraved).
 
 Thanks
 |  | 
	
		| Back to top |  | 
	
		|  | 
	
		| 45PSS 
 
 
 Joined: 28 Sep 2001
 Posts: 4081
 Location: Mid Peninsula, Ca.
 
 | 
			
				|  Posted: Tue Nov 14, 2006 8:34 pm    Post subject: |   |  
				| 
 |  
				| 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.
 |  | 
	
		| Back to top |  | 
	
		|  | 
	
		|  |