Re: B&W IE

[boblong@xxxxxxxxxxx (Robert Long)]

On Mon, 14 Oct 1996 05:26:43 +0100, you wrote:

|Bobbi posted here meter settings of around 2000. This sounds to me like =
the
|meter is *very* sensitive to IR! If the meter wasn't sensitive to IR,
|wouldn't the settings have to be around 12 or 6 to compensate?
|
|Correct me if I'm wrong please...

I'm afraid I must.  Let's say that the correct exposure for a given
scene is f/8 at 1/250 sec. for an EI of 200 and that the meter has an
IR-blocking filter that absorbs all but 10% of the red and infrared
coming through the filter in use.  The meter will "see" so little of
the light coming through that combination of filters (that on the lens
and that on the metering) that it will claim a shutter speed of 1/25
sec. will be necessary for correct exposure.  The only way to get the
correct setting will be to advance the camera's EI setting to 2000.
That will net you the correct exposure settings.

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Topic No. 2