Re: APS Bushwah From Peterson's

[P3D Greg Erker <erker@xxxxxxxxxxxxxx>]

>     "Third, because the light transmitted by the lens doesn't have to spread
>over as large an area to cover the smaller APS format, the APS image is about
>one stop brighter. Thus, in a given light level, ISO 200 APS film will let
>you shoot at the same shutter speed and f-stop that would require ISO 400
>film in a 35mm camera."

  There was a discussion of this in one of the rec.photo groups
a week or two ago.

  I think it relates to having an APS camera that takes 35mm
SLR lenses. Then if you have a negative teleconverter (so that
your 28 mm lens gives the same angular coverage as it did on
35mm format) the lens ends up about one stop faster. I.E. if you
put a 1.4x converter on the lens it gets one stop slower, so if
you put a 0.7x converter on the lens it gets one stop faster.

  Peterson's misunderstood this and generalized it to refer to
all APS cameras.  I stopped reading the thread after a few
messages so I may be slighlty off but still closer than
Peterson's :)

Greg E.



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