Gary Reese wrote:
>
> It is in Norman Goldberg's "Camera Technology - The Dark Side of the
> Lens" (Academic Press, 1992). He invented the procedure and it is
> described on pages 239 to 241. It involves using a white hemispheric
> dome flooded with indirect light, with the test lens inserted within the
> illuminated dome. But dead center is a dark point. Flare is measured
> with a fiber optic and photomultiplier and light levels read on an
> oscilloscope. The test compares readings off the black center versus
> readings when a white object is placed in front of that black center.
> Lens flare prevents the image of the black center from being truely
> black, thus the "percentage flare" reported in the lens tests.
Thanks gary, sounds like a pretty objective test. It would also be possible
to measure the effect of various lens hoods using that technique, I wonder
if that was done ?
>
> The same book describes all the other tests Goldberg devised for Popular
> Photography's testing lab in the 1970-1980s.
>
Sounds like an interesting read.
Is Norman Goldberg related to Rube Goldberg ?
...Wayne
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