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View Full Version : Lens tilt offset and View Camera bellows



John Dorio
14-Apr-1999, 16:06
Does anybody know what the lens tilt offset is for a 150mm lens that is on a vie w camera focused at infinity and sits 5.5 ft off of the ground? (I'm referring t o the offset in the image circle) This is for landscape and the lens is downtilt ed. Also will the focus shift on distant objects when the lens tilt is varied ev en though the lens is focused at infinity? What are the advantages and disadvant ages of having a leather bellows instead of a synthetic one? Which is better?

Alan Gibson
14-Apr-1999, 21:20
What a lovely collection of questions.

>> Does anybody know what the lens tilt offset is for a 150mm lens that is on a view camera focused at infinity and sits 5.5 ft off of the ground? (I'm referring to the offset in the image circle) This is for landscape and the lens is downtilted.

The lens tilt angle will be about atan (150mm / 5.5ft) = atan (150/1676) = 5.1 degrees. Assuming axis tilt, this will shift the image up by tan(5.1) * 150mm = 13.4mm.

>> Also will the focus shift on distant objects when the lens tilt is varied even though the lens is focused at infinity?

In general, yes.

>> What are the advantages and disadvantages of having a leather bellows instead of a synthetic one? Which is better?

Old leather gets marked by rain, which is a shame.