DSLR-Cooled Vs Not Cooled

By Steve Mohr

A Basic Comparison between the Standard DLSR Vs a Cooled Version – 10 minute Exposures

This isn’t really a report, but simply a basic comparison to show what the visual performance difference between the Hutech Canon 40D (Standard DSLR with modified astronomical filter) and the Central DS Canon 40D (Peltier Cooled DSLR with modified astronomical filter)

Before I go ahead, central DS have already provided a sample of images with and without their cooling option employed:

http://www.centralds.net/en/index.htm

Note: this site has excellent developmental information of their design, which is interesting reading.

The following images show the difference between the:

1. Hutech Camera: one 10 minute exposure following a string of four [4] previous 10 minute exposures, ISO1600:

2. Astro 40D: one 10 minute exposure following a string of four [4] previous 10 minute exposures – Cooling OFF, ISO1600:

3. Astro 40D: one 10 minute exposure following a string of four [4] previous 10 minute exposures – Cooling ON, ISO1600:

Another interesting item I noticed was that the file sizes (not dimensions, nor pixel size being different) were increasing in size with increase of noise (data). The following jpeg image sizes where experienced:

Hutech Camera: one 10 minute exposure following a string of x4 previous 10 minute exposures: Size 11,756 kb

Astro 40D: one 10 minute exposure following a string of x4 previous 10 minute exposures – Cooling OFF: Size 6,901 kb

Astro 40D: one 10 minute exposure following a string of x4 previous 10 minute exposures – Cooling ON: Size 2,778 kb

There you go!