After having learned the positive effects of simple cooling measures i have made some attempts to develop a modification to the watec camera housing that provides for forced air cooling through a small fan.
Here are some images of my first attempt.
The standard camera covers were replaced with two pieces of aluminium, to which a 40mm standard fan was attached. The front-plate of the camera was modified, so that air could flow through the small chamber, which contains the ccd-chip. The fan blows the air from the top of the case across all circuit boards. As there is only a very small gap between the front plate of the camera housing and the ccd-chip-housing, i dont expect stray light to be much of a problem.
|The modified camera, with fan on top, from behind. The gaps between fan and original back-plate need to be closed, so that all air is forced through the housing.|
|A small hole had to be machined into the left camera cover, to accomodate the (useless) connector for the iris-controlled lens. Might the connector simply be soldered out?|
|From the front, the circuit board of the ccd-chip is visible, as some of the frontplate has been removed, to allow air to flow.||Another image.|
|From above, through the operating fan, all the circuit boards and the ccd-chip (as the rightmost chip) can be seen. There is a very small gap between ccd-chip-front and the backside of the camera front-plate. Where there is light, air can flow, too.|
|From below, no cover has been installed yet. Some kind of protection will be required. The machined opening in the frontplate, through which the air can flow across the ccd-chip, can be seen at the right of the housing.|
|A dark image of the unmodified camera at room temperature, no airflow, maximum gamma settings to show the hot-pixels at their worst.|
|The dark image of the modified, cooled camera shows the positive effect very well: All the weaker hot-pixels have disappeared.|
I have a more simplified and sturdier version of this mod in mind using 50x50x5 Aluminium profile, which would also be easier to build. Of course, a final version would also be painted/anodized black and should be better looking.