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The Lumen is a measurement of the intensity of light.

learn more… | top users | synonyms

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Brightness of LED panel [duplicate]

If choosing a xenon flash, GN is a common reference. Come to led panel, there is lm/m and lux. This is a spec. of led panel: LM: 520/m LUX: 1m: 650, 2m:170, 3m:80 Whats EV equivalent of above ...
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2answers
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How can I measure luminance values from different cameras?

Calculating EV and then Lx is pretty simple. The problem starts when trying to calculate these by using EXIF data that come from different cameras. I tried capturing a static object in the exact ...
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2answers
492 views

What is the lowest level of luminous flux a camera can detect?

In the past, I've asked about taking photos of luciferase. Now I'm curious how weak of a light source I can detect. From How many photons per second is one Lumen? on Physics Stack Exchange, I can ...
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800 views

How to compute luminous intensity in a photograph?

I have a photograph in raw format taken by a Nikon D-90 camera of a white LED spotlight shining on a wall in an otherwise dark room. I need to compute the relative luminous intensity of the bright ...