I brought the dark-field exposures of the previous post — plus a few more so that I has an exposure every 1/3 stop — into RawDigger, selected the central 90% of the frame, and measured the standard deviation of the read noise. I normalized the results to a full scale count of 16383, and here’s the… [Read More]
Archives for July 22, 2014
Nikon D810 dark field histograms
Here are a series of D810 raw histograms of a dark field at selected in-camera ISO settings. The field I chose was the back of a Sigma 50mm f/1.4 DG lenscap. To make sure it was really dark, I set the lens to f/16 and the exposure time to 1/8000 second. I used single shot… [Read More]
Nikon D810 self-heating
Before I start seriously testing a camera, I make a series of dark field exposures to see if there are self-heating effects that would compromise results made with rapid series of shutter activations. Of late, it’s not been a problem. Here’s the standard deviation of each raw channel for a series of exposures of a… [Read More]