the last word

There’s enough data in the test exposure that I talked about at the beginning of this series to calculate the full-well capacity of the photosites in each camera, if we make the reasonable assumption that the manufacturers of the cameras set the gain of the amplifier at base ISO so that the ADC clips at… [Read More]

As you might expect, there is a strong correlation between Unity Gain ISO and pixel pitch. The Leica M9, the only CCD (and, I think, the only non-Sony) sensor in the bunch , is an outlier.

A Nikon D800E produces these results at a count of around 500: The Sony RX-1 at a count of around 4000 looks like this: And at a count of 500, it’s a little different: The Leica M9 at Zone VI has a pronounced hump: The Sony NEX-7 had anomalous behavior at ISO 6400: We saw… [Read More]

There’s a technique on the RawDigger site for determining the unity gain ISO for a camera by using photon noise. The scheme is basically a search over a range of ISO values to find the one where the square root of the average value of a group of similarly-exposed raw values equals the standard deviation… [Read More]

The Sony RX-1 has a small battery; it looks like the designers decided to double down on small size and light weight. There have been some complaints — although non from me — about the RX-1 battery life, which has usually been enough for me to make 400 or 500 images. I use a 1600… [Read More]