75 shift lens DOF

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I am interested in increasing the DOF of landscape shots. Does the Pentax 75mm shift lens enable enough tilt to increase DOF? And if so to what amount? Don

-- Don Singer (dons@grand-canyon.az.us), August 18, 1999

Answers

Don, you have hit upon a weakness in the P67 system. That is why I have proposed that Pentax offer smaller stops on several of their lenses. See my post on this subject elsewhere in this forum. A 75mm with an f/45 stop would be nice. SR

-- Steve Rasmussen (srasmuss@flash.net), August 18, 1999.

I don't believe the 75mm has tilt capability.

-- Willie Ju (wju@mediaone.net), August 18, 1999.

The 75mm shift lens for the Pentax 6x7 has no tilt capability; it only has shift, a 20mm off-axis raising or lowering of the lens as well as diagonal movements. Since the lens is about the equivalent of a 37mm in 35mm format, the best you can do is use hyperfocal distance focusing and stop the lens down (it goes down to f32); but since it will give you a 75mm lens' DOF, even at f32 you are not going to get the same depth in the shot as you would from a 35mm shift lens in the small format. For exterior architecture and landscapes though, it's quite a good lens as long as you are not too close to the object in the foreground that you want rendered sharp while holding background sharpness as well. I will say that it has outstanding resolution and contrast. Oh did I mention it's rather large and a bit heavy?

Charles Shoffner

-- Charles Shoffner (chasmn@aol.com), August 20, 1999.


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