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I need to know my camera's quantum efficiency for a research project which involves the usage of a Nikon Coolpix A10. Is there some way to know it?

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Measuring QE without a NIST-calibrated standard is nontrivial. It's even harder when you have to deal with the analog gain applied prior to storing the RAW image's A-to-D values.

On top of that, the QE is strongly wavelength-dependent, so unless your project is using lasers or other narrowband sources, you are in a deep pile of youknowwhat.

If you do have a laser source, there is an indirect method that may work if your camera's electronics noise is small enough. The technical term is "signal-limited noise," meaning the photon shot noise is larger than all other noise sources in the system. If you're in that regime, you can collect data (images) over several input levels , or equivalently several exposure times, and compare the variance in each pixel's signal vs. the mean value. Since shot noise, i.e. standard deviation, follows a simple rule that Noise = sqrt(signal), you can back-out the QE from the slope of the curve.

If that physics hasn't overwhelmed you, you might want to read the info at RochesterInstTechPhysics or This easy blog post

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  • \$\begingroup\$ Hey! thanks for the answer and the interesting articles. I think I might have gotten misdirected in my work. Could you please confirm whether quantum efficiency is of a photodiode only, and thus the photodiodes that collect information of R, G and B will have the same quantum efficiency? Bayer filter and others won't affect it \$\endgroup\$ Commented Jun 23, 2016 at 6:44
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    \$\begingroup\$ @EkdeepSinghLubana "Quantum efficiency" is the detection rate of the photodiode, but what matters to you is "Detective Quantum Efficiency" aka DQE, which takes into account the system losses. Since each Bayer filter element transmits less than 100% even in its own color band, the filters do have an effect on the net DQE. \$\endgroup\$ Commented Jun 23, 2016 at 11:59

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