Taking photos of displays...

From: der Mouse <mouse_at_Rodents.Montreal.QC.CA>
Date: Mon, 28 Feb 2005 14:10:04 +0000

>> I suspect you may have to put the camera on a tripod (or equivalent
>> means of keeping it fixed) and take something like a dozen pictures
>> and then digitally average them, to get the equivalent of a long
>> exposure with a slow film.
> Little bit of a problem with that logic...you would want to
> "accumulate" or "sum" the light from shorter exposures to simulate a
> longer one, not "average". And if the light is low enough you could
> end up summing a bunch of "0"'s in any case....

Both true. I was actually being a bit too abbreviated. I was assuming
you'd be using normal lighting, under which circumstances the only
problem with an ordinary digital snap would be the banding on the CRT.
And if they're all decent pictures except for the banding, averaging is
a decent tack to take. (Assuming of course that the camera's "shutter"
timing is random with respect to the monitor's vertical scan, which is
probably a reasonable assumption.)

After all, long exposure makes the picture more exposed (as compared to
a shorter exposure, other things constant); slow film makes the picture
less exposed (as compared to a faster film, other things constant). So
you long exposure plus slow film adds up to wanting the "normal"
lighting conditions. And that kind of lighting is what you want for a
digital camera anyway.

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Received on Mon Feb 28 2005 - 14:05:33 GMT