10 jun 2007 kl. 21.24 skrev trevor cunningham:
hey gang, was hoppin' around ebay and found an interesting product...an adaptor to fit any mamiya 645 lens to a nikon d200...i have such equipment, and, coinkidinki being, intend on purchasing a d200...just wondering what type of focal length and perspective translations are implied if i have a 35mm 645 lens pointed at the d200 sensor...or my 80mm at that...i believe the equivalent for a 35mm camera is around 16mm, but my math could be way off...would that make it like a 24mm lens on the d200? too lazy to look into the math that much
Just multiply the true focal length by 1.5 to get the "equivalent focal length" for a 35 mm camera. The fact that the lens was intended for another format than 35mm is of no consequence for the maths here.
So your 35 mm lens will give the same field of view as a 52.5 mm lens on a 35mm camera; so it will work like a "normal" lens (in fact, inexpensive used 35/2.0 AF Nikkors are popular and convenient as normals for the D200). An 80 mm lens would work like a 120 mm lens does on a 35mm.
Obviously, there are practical problems and considerations: no autofocus, no auto stop down, no exposure metering. Also, since the Mamiya lenses were optimized for a far larger format, it may well have far lower resolution than lenses made for a digital Nikon.
So, honestly, unless you have some more special optics for the Mamiya (a bellows with short-mount macro, or a very long tele lens), it´s probably not worth the hassle. In your case, you´ll just get a very slow working normal...
Per Öfverbeck http://ofverbeck.se "In a world without walls or fences, who needs Windows or Gates?"
