In the previous post, I modified BIll Claff’s photographic dynamic range criterion slightly, and used it to compare several cameras. Today, I’d like to add one more camera, the Sony alpha 7S, and compare the photographic dynamic range of all four vs ISO. The Claff SNRs (see here for explanation) of the four cameras are:… [Read More]

I left off yesterday’s post with two questions about comparing shadow noise performance of cameras with different resolutions: What should we pick for a common resolution, and what value should we pick for a barely-acceptable SNR? Thinking that I couldn’t be the first person to ask these questions, I thought to look around to see… [Read More]

For the past few days, I’ve been reporting  on the “ISOlessness” of three cameras — the D4, D810, and alpha 7II — using a metric that I devised which, given an ISO range and a shadow level, returns the signal-to-noise ratio (SNR) of that level at the highest ISO in the range and at all the… [Read More]

I went back to the D4 and D810 data sets and ran the ISOlessness test on them without any data set scrubbing. Here are the results with a target mean of 0.01 for ISO 6400 for the D4 and ISO 4000 for the D810 (the tested ISOs are two-thirds of a stop apart because the… [Read More]

I have developed a test for “ISOlessness” as part of the photon transfer analysis program. The test is described here. Here’s a summary: You specify the highest ISO that you wish to consider, and what the mean signal level should be at that ISO as a ratio to full scale. For example, if you’re interested… [Read More]