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Mark_3705
17-Jul-2004, 00:43
Hi, I just read Stephen Shore's interview in View Camera magazine. It was interesting to see that they listed the camera and lens that he shot each picture with. I am a student using a medium format camera (Mamiya RZ 67) but really like this work and would like to shoot images with the same look.

Can someone tell me the medium format equal to these large format lens

8x10 Lens 305mm G-Claron 300Symmar-S

4x5 Lens 135mm Xenar

Thank you for your help and time with this.

Mark

Gregory Owens
17-Jul-2004, 01:15
Mark,

A 300mm lens is considered a "normal" lens for 8x10 format, based on the film diaganol of 312 cm and a 135mm is "close to normal" for 4x5 (151mm film diagonal). Translated to 6x7cm format, you would want to use either an 80mm (300) or a 75mm (135) lens . I hope that answers your question satisfactorily.

Cheers, Greg

Darin Cozine
17-Jul-2004, 01:17
Mark, its not quite a 1 to 1 comparison. Most 35mm cameras shoot 24x36mm frames. this equals about a 1:1.5 ratio. Large format film is usually either 4x5 or 8x10, both are 1:1.25 ratio.

So with 35mm film you get a wider frame. This makes the angle-of-view comparison a little harder. I like to concentrate on the short side when I compare focal lengths.

You can use these calculators to get your answers:

http://www.imaginatorium.org/stuff/angle.htm

http://www.mat.uc.pt/~rps/photos/angles.html

Jim Rice
17-Jul-2004, 01:20
Darin, He's shooting 6x7.

Ernest Purdum
17-Jul-2004, 07:40
You mention the 135mm Xenar in connection with 4X5. This would not be a good choice for a view camera, since it has too small an image circle to permit any use of movements. The G-Clarons and Symmar S lenses operate at a wider angle of view and are good choices for view camera use.

Leonard Evens
17-Jul-2004, 09:13
6 x 7, 4 x 5, and 8 x 10, all have just about the same aspect ratio. 6 x 7 is actually pretty close to 56 x 70 mm, and 4 x 5 is close to 95 x 120 mm. So the multiplier for going from 4 x 5 to 6 x 7 is just about 7/12. Going from 8 x 10 to 4 x 5 the multiplier is pretty close to 1/2. So going from 8 x 10 to 6 x 7, the multiplier is close to 7/24.

So a 135 mm lens with 4 x 5 has pretty much the same angle of view as a 6 x 7 lens of focal length 7/12 135 = 78.5 or about 80 mm. Similarly, a 300 mm (or 305 mm) lens with 8 x 10 has pretty much the same angle of view as 6 x 7 lens of focal length 7/24 300 = 87.5 or about 90 mm.

P.S. A 135 mm lens for 4 x 5 is actually slightly wide. The "normal" focal length is 150 mm. But you wouldn't notice an enormous difference. 90 mm is usually considered "normal" for 6 x 7.