thanks for the link to another post , It helped a bit, but Im still confused by what is acceptible in applying a dark at say 20C to an image at 23C, although I assume that if the start piont is the same ,ie 21.7C same exposure lenght and cool down then the temperature increase inside the camera will be the same and the darks will be adequate,
but what is the margin of acceptibility...?
I guess its trial and error, huh ...
