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Author Topic: Best Meter for Measuring Screen Brightness?
Chris Rasmussen
Film Handler

Posts: 7
From: Berkeley, CA, United States
Registered: Feb 2005


 - posted 09-11-2009 07:43 PM      Profile for Chris Rasmussen   Email Chris Rasmussen   Send New Private Message       Edit/Delete Post 
Greetings!

A tech who's borrowing my Pentax Spotmeter V says it's insufficient for reading screen brightness due to shutter strobing.

Can someone suggest a better meter or a way of interpreting his readings (he already has the conversion to foot-lamberts).

Thanks!

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Karl Borowski
Expert Film Handler

Posts: 161
From: Sulking in GameFAQ Forum
Registered: Sep 2009


 - posted 09-11-2009 07:44 PM      Profile for Karl Borowski   Email Karl Borowski   Send New Private Message       Edit/Delete Post 
You can use lightmeters for reading ft.-L's? I always thought this had to be done with specialized equipment. . .

If you do have formulae available for converting meter readings to ft.-L's, I'd appreciate if you could post some here!

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Steve Guttag
We forgot the crackers Gromit!!!

Posts: 12814
From: Annapolis, MD
Registered: Dec 1999


 - posted 09-11-2009 07:59 PM      Profile for Steve Guttag   Email Steve Guttag   Send New Private Message       Edit/Delete Post 
The problem is in the averaging...for working with film projectors, the spot meter must average the light over cycle of the shutter.

Most photographic meters measure incident light. For Cinema, one is interested in what bounces back off the screen (reflected light).

As for meters...the USL PSA is by far the most useful of them. It is like having 45 light meters in one unit...not only will you know what the light level is but also its distribution. They even have the ability to judge flicker and image jump. And when you are done, give you a print out as a reference.

One of the problems I find with most measuring equipment is the people operating it...they often don't follow procedures or realize what they are doing and thus get erroneous readings.

Steve

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