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View Full Version : 240mm Kowa Graphic (Computar) covers 11x14?



Gene McCluney
29-Apr-2007, 19:48
have a Kowa Graphic (Computar) 240mm lens on trial, It is in barrel mount. I have mounted it on a lensboard where the rear element penetrates the lensboard and is flush with the rear of the lensboard. A Packard shutter is mounted flush up to the rear, so it basically touches the metal rim of the rear of the lens. I am getting vignetting on 11x14 focused at infinity at f64. I was wondering if this lens only covers 11x14 when mounted in a shutter? Any advice? It IS supposed to cover 11x14 isn't it?

Jason Greenberg Motamedi
29-Apr-2007, 20:55
Not all Kowa Graphic lenses are the same design as the f9 Computar lenses. I can't recall the details, but it seems to me that some of the Kowa Graphic lenses were 6/4 plasmats identical to the f9 Computars and others were 4/4 design (dialyte?) with much less coverage.

Gene McCluney
29-Apr-2007, 21:17
Well, it is an f9, if that tells you anything.

Jim Galli
29-Apr-2007, 21:21
Gene, you'll have to take the factory lens shade off for 11X14 and 7X17. Then it should cover with a little movement.

Tony Karnezis
29-Apr-2007, 21:53
The Computar lens and ULF coverage.
http://www.largeformatphotography.info/forum/showthread.php?t=10255

Sandy King has posted the image circles of the Kowa/Computar lenses and the formats they cover. The IC of the 240 Computar is roughly 523 mm, far greater than the 450 mm IC required to cover 11x14.

Gene McCluney
29-Apr-2007, 23:48
Gene, you'll have to take the factory lens shade off for 11X14 and 7X17. Then it should cover with a little movement.

There is no lens shade on this lens.

Jim Galli
30-Apr-2007, 06:28
Have you got a snap shot of the lens Gene? I have the 240 and the 270, both in the barrel where the rear group is "built in" so they can't be shutter mounted. The 270 is much longer physically and vignettes an 11X14 with any movements at all. The 240 is short coupled and has a removeable cone shaped shade at the front. iirc I could get about an inch and a half rise with that 240 on the 1114. There seems to be enough different iterations of the Graphic Kowa lenses to completely drive you nuts.

Gene McCluney
30-Apr-2007, 08:01
According to the owner of this lens I am trying out, this lens originally had a permanent front element, the rear element is removable. The lens was sent to Grimes who made a new removable cell for the front glass and modified the barrel so the front cell would screw in..so as it now stands this lens has removable front and rear cells. It is supposed to screw into a Copal 3s shutter, but I don't have one of those to try.

kleinbatavia
13-Jul-2017, 11:27
Hmm, I'm late to the party, but it ought to cover...

Lachlan 717
13-Jul-2017, 12:52
Hmm, I'm late to the party, but it ought to cover...

Me, top.

I have one that easily covers 7x17"; slightly bigger IC than 11x14".

It's recently been replaced with a 210mm...