Cold camera photography

Cold camera photography is a technique used by astrophotographers to reduce the electronic noise that accumulates during long exposures with the electronic sensors in DSLRs and dedicated CMOS or CCD astro-cameras. Cooling is usually accomplished with a Peltier thermo-electric cooler. By cooling the camera's sensor one can take longer shots without the worry of the chip heating up, thereby reducing thermal, shot and read noise.^[1]

For astrophotography in the near infra-red, such as with the James Webb Space Telescope, cameras are cooled to cryogenic temperatures in order to eliminate thermal noise sources. Cryogenic cameras for infra-red imaging are used on Earth for many purposes. (Cameras that are designed to operate in cryogenic environments are also referred to as cryogenic cameras.)

For traditional film cameras, cooling is required to reduce the Reciprocity Effect (or Reciprocity Failure), in which the effective film "ASA" sensitivity decreases with time in long exposures. That reciprocity is different for each color in the emulsion, and so it also leads to color-shift in the final image. Cooling of chemical emulsion film is usually achieved by using a cold camera that is dedicated to cooled astrophotography. Cooling in this case is usually achieved by contacting dry ice to a platen that is in turn contacted to the film.^[2] This technique was popularized by renowned astrophotographer Jack B. Newton, and even earlier, Evered Kreimer used his own design to obtain the images in the Messier Album that he co-authored with John Malias.