One question that naturally arises from the last few days’ read noise self-heating tests is how to compare this a7II curve: With this a7RII curve: First off, we have to deal with the resolution differences. The a7RII image is 8000 pixels wide. The a7II image is 6000 pixels wide. So the a7RII looks log2(8000/6000) =… [Read More]
Search Results for: a7RII self heating
a7RII self-heating for long exposures
There have been reports of strong self-heating effects at long exposures with the Sony alpha 7R Mark II (a7RII). I mentally discounted them, because I didn’t know of a mechanism that would preferentially heat the sensor with the shutter open and the photodiodes sitting there back-biased and waiting to snag a passing photon. But the… [Read More]
Sony a7RII self-heating
Before I get too far into testing a camera, I do a series of exposures calculated to see if there are self-heating effects that might skew my test results. Since many of my tests involve making series of sequential exposures that are later subjected to statistical analysis, material self heating can force me to slow… [Read More]
Sony a7RII long exposure battery current draw
I’ve been made aware of an objection to the Sony a7RII star-eater workaround that I documented in this post. A poster on Fred Miranda claimed that using continuous mode would result in greater sensor heating (and therefore more read noise) than using single shot mode. That didn’t seem right to me, but things that seemed nearly self-evident… [Read More]
Worst-case Sony a9 self heating
This is the 23rd in a series of posts on the Sony a9. The series starts here. In this post, I tested a fairly severe a9 use case and found: A rise over ambient looked like it was going to get to about 17 or 18 degrees C above ambient. A time constant of about… [Read More]