Saturday, December 10, 2011
The links below provide a more complete description of the base cooling system. Additions will be forthcoming, describing other functions.
UPDATE: In Part 3 of 3 updated circuit diagram and component and PCB modification. The board shown in Part 3 and the PCB etching pdf are the same, except that the traces are slightly modified in the etching file for neatness.
Appendix 1 Canon 1000D Thermoelectric Cooling Conversion - PCB etching. This is the basic board - updated.
Appendix 2 Canon 1000D Thermoelectric Cooling Conversion - Arduino/Teensy Code txt file. New version - corrected error to pwmV code.
Appendix 3 Canon 1000D Thermoelectric Cooling Conversion - Arduino/Teensy Code - .ino file New version - corrected error to pwmV code.
Why cooling - a very basic explanation
For anyone not familiar with the reasons for cooling a digital camera sensor. The purpose is to reduce dark noise (thermal current) generated during long exposures - the result of sensor heating.
Reducing the temperature at which an image is acquired improves its quality because signal to noise ratio (SNR) is improved.
The cooling system described here, dependent on Thermoelectric module (TEC) and heatsink rating, is capable of reducing sensor temperature between 18 and 30C.
Sample images taken with a cooled Canon 1000D 200mm prime lens f5.6 and f6.3.