Measuring Lighting Non-Uniformity Using a Camera

The issue with performing lighting uniformity measurements using a camera is that the actual luminous flux may be hard to derive from the digital number, depending on your camera's auto-exposure it is more useful for relative measurements. Also, measuring lighting nonuniformity with a camera conflates the camera nonuniformity with your lighting non-uniformity. Photometric calibration of each pixel is the best way of preparing a camera for this sort of test. An easier, but marginally less accurate, way would be to use just the center portion of a low-vignetting lens. This is described at the bottom of this page https://www.imatest.com/2018/01/lightbox-uniformity-comparison/ .

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