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Amazing lens, incredible sharpness

Started Aug 20, 2013 | User reviews thread
thk0 Regular Member • Posts: 159
Re: Well, what do you mean by 1.8?

Great Bustard wrote:

thk0 wrote:

Great Bustard wrote:

thk0 wrote:

I was questioning whether eg 4x more total light (ff at same f-stop) gives exactly 4x less noise.

4x as much (2 stops more) light will result in 1/2 as much (1 stop less) photon noise. The other player is read noise (the additional noise added by the sensor and supporting hardware).

Got it. Done my homework. SNR scales as sqrt intensity for shot noise.

The SNR is proportional to the sqrt of the total amount of light (as opposed to the intensity of the light) that falls on the sensor.

I knew you were going to say that as soon as I posted. I omitted for a constant area. Yes, total light as you say.

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