The mechanical shutter on the Sony a7RII is supposed to be better damped. It also has electronic first-curtain shutter (EFCS). How do those things make moderate telephoto pictures sharper? The protocol: The cameras: the Sony a7RII and Sony a7R. The lens: the Leica 180mm f/3.4 Apo-Telyt-R The filter: Heliopan 77mm variable neutral density. The lighting: a… [Read More]
Archives for August 8, 2015
a7RII bulb mode spatial filtering at ISO 100, 400, & 1600
I was asked if the spatial filtering mentioned in the previous post that takes place in bulb mode at ISO 6400 also happens at other ISOs. I tested three of them. It looks like the filtering is nonlinear, since it has different effects at the different read noise levels of different ISOs. I assume, but… [Read More]
Sony a7RII bulb spatial filtering
The other alpha 7 cameras switch from 13-bit to 12-bit precision when the shutter is set to bulb, even if the shutter mode is single shot. Is that the case with the a7RII? Yes, indeed. Here’s the histogram of a 6-second single shot, ISO 6400, dark-field exposure made using the camera’s shutter timing mechanism: Every… [Read More]