the last word

In several recent posts, there were reductions in dark-field noise at high ISOs with the a7II and a7RII that I attributed to in-camera processing. Spectral analysis of the images confirms this. For the a7II, on both sides of the transition point: fs is the sampling frequency. Values from dc to the Nyquist frequency are plotted… [Read More]

Last Saturday night, my wife and I went to dinner with two artists who were in town for a workshop (My recovery has progressed to the point where I can now get around with a cane.) She’s a watercolorist; he works with oils. She asked an interesting question, which I will paraphrase as: “How does… [Read More]

In the previous post, I noted small (sub LSB) differences in average dark field images from compressed and uncompressed raw files from the Sony a7RII. This post repeats the testing and plotting for the a7II. I took a look at the mean values of a 200×200 central square of the same raw dark-field images that… [Read More]

Jack Hogan, in a comment to an earlier post on the rms noise values of uncompressed and compressed Sony a7rII dark-field images, wondered if there was digital multiplication going on, and, if so, would the mean values be affected. I took a look at the mean values of a 200×200 central square of the same… [Read More]