I've acquired a used ST2000 camera that is frosting over in a manner that is unlike anything that I have seen in my experience with the STX series cameras.) I have replaced the desiccant plug with the Farpoint system and can keep from frosting over as long as I do not operate the camera less than -20C. This might be because I am in New Mexico and the relative humidity is quite low especially in the cooler months. I suspect a leak into the main chamber. I did take the front off of the camera to inspect the CCD chamber and was curious if it is possible to replace the big o-ring? Is this part available or does someone know of an equivalent replacement? Thanks, Mike
McMaster Carr makes a range of large o-rings. You may be able to find an equivalent. Details on their website here: https://www.mcmaster.com/catalog/129/3963/9396K132 That one is typically for the filter wheel. There are others on that page, and you may find a suitable replacement. (I don't have an exact part number for you, sorry).
Here are McMaster part numbers for the O-rings used in the ST-2000 housing: 9557K67 (there are two of these) 9557K125
