On 05/07/2007 gary wrote:
> Seems to me the camera should be able to compensate for the
> vignetting.
> It "knows" the lens and the sensor, so it should know the light
> falloff.
There are software strategies for dealing with both vignetting and
chromatic aberratuon artifacts, also barrel/pincushion distortion and just
about any other drawing issues that lenses get wrong onto a flat surface,
but processing power so far means they're post-prod techniques done on the
computer rather than in cameras.
The Leica M8 Kodak sensor uses microlenses that are progressively angled
toward the lens axis to increase light-gathering power near the edge of
the frame. Vignetting still occurs with short lenses at wide apertures,
but given the short back focus of the lenses involved, presumably it'd be
worse without.
Then you have Olympus producing telecentric-ish lenses so off-axis rays
are perpendicular(-ish).
If all else fails I still have the Kodak Brownie 620 I was given as a kid,
a tin box with a 2 element lens stuck in the front. That wasn't perfect
either, but I can't say it mattered :)
--
Regards
Tony Sleep
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