In this lesson from "Mastering Exposure: Learn by Video", Tim Grey guides you through some of the issues related to the capture of long exposures. For more information about this video training title, go here:
http://timgreystore.com/index.php?app=ecom&ns=prodshow&ref=ExposureLBV
ShootingOutside - You're absolutely right that ambient temperature has an effect on some of the sources of noise in a digital capture. That's part of the reason that some specialized astral photography makes use of refrigeration for the image sensor. It makes a huge difference!
thetimgrey 6 months ago
Picked up your tip on heat building within the camera for long exposures, which produces more noise. The question is, this may not be controlled only by long exposure but the ambient temp also. So that on a hot day noise may well be increased even more than on a cool day. Great tutorial Tim.
ShootingOutside 6 months ago