My astronomy project:
Sensor dryer stains

Contents:

1. Dryer stains
2. Sealing the chamber and desiccant
3. Three nights outdoor tests
4. During work

Note:
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2: Sealing the chamber and desiccant

I have already tried to seal the chamber between the lens and camera to get it light tight. But to make it tight for moisture is more advanced. First I install some desiccant to see if it has some effect on the moisture problem as the construction already is.

Desiccant chamber:

If this desiccant helps to keep the dew away from the sensor. I make a new off-axis adapter where there is space for a chamber where I can put the desiccant into.

Openings that I have closed to some degree. Left is the opening to the guide camera, the opening for the tilt mechanism and bayonet are sealed by the black tape. This also protect it for dust to enter the chamber.

Prepare for a test:

To get some proof that the desiccant helps I have to put them inside the camera or the lens for a test. No way to fit the desiccant bags here.

On the back side of the lens there is more space. Still the bags are too big to fit inside.

I have a smaller bag of desiccant, this one I got to fit inside the lens barrel. It will cause some unwanted reflections, but that doesn't matter, I only want to know if it keep the moisture away. They are hold in place with a stripe that press the bag outwards to the barrel. Strange that the silica gel is held in a plastic bag, could moisture really go through this plastic bag ?