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Tutorial: Camera time efficiency simulation

5: Thermal Noise, example 3

I was curious to see how the thermal noise from an uncooled DSLR camera influence the total S/N. With the latest version of my Excel sheet I can simulate and calculate dark current and thermal noise. If you are lucky and live in a cold climate country as I do with temperatures around zero degrees or lower it doesn't increase the total S/N very much, but if you have +10 degrees or more it's bad. Here is a screen dump that show how it differ from Example 1 with 0 o C sensor temperature on the Canon 6D DSLR camera:

Test with different input parameters, you will see interesting things happen. Look at the Canon 6D at ISO800, sensor temperature 0 o C degrees (example 1) and +15 o C degrees (example 3):

Compare above Step 2 with example 1: Thermal Noise, 6.8 vs 16.1.

Compare above Step 3 with example 1: S/N, 17 vs 15.

In this example I have set the temperature for the cold cameras to -20 o C (red field), I think that is good a value in normal climate countries. The DSLR camera sensor is set to +15 o C, to have that on my Canon 6D sensor the out door temperature has to be +9 o C or lower. The camera built-in temperature sensor that measures the cameras inside temperature is 6 o C above the surrounding temperature. If I use the live view the camera increase the inside camera temperature with a whopping 20 to 25 o C degrees relative the surrounding temperature, that take a long time to cool down again.

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