On 02/04/2001 08:36, Rodger Whitlock opined:
>Note, btw, that the shift lens uses quite a different optical formula
>from the M and K series 28mm f/3.5 models.
I would expect so, given that the circle of useful image has to be at
least 22mm larger than a normal 35mm lens, which has to cover a minimum
of 44mm with no light falloff and minimal loss of sharpness.
This lens has to cover a 66mm circle, a bit less than the 76mm needed for
a 45 x 60 image.
But to save money, it might have used a 645 lens design, given that the
mechanics for shifting set the optical group at least another 10mm
further from the film plane. It would be interesting to compare the
design to the Pentax (or others) 40 to 50 mm lens for 645 cameras.
All measurements rounded up, in case anyone wants to pick nits.
JoMac
JoMac, Imagineer with Camera
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