1° Forum di Astronomia Amatoriale Italiano

B.2. Regenerating the Desiccant
This section describes the regeneration procedure for the desiccant used in the ST-7XE, 8XE,
9XE, 10XE, ST-10XME and ST-2000XM. The desiccant absorbs moisture in the CCD chamber,
lowering the dew point below the operating temperature of the cooled CCD, thus preventing
the formation of frost. The desiccant is contained in a small cylindrical plug that screws into the
chamber from the rear. In normal operation the useful life of the desiccant is over a year. If the
CCD chamber is opened often, the desiccant should be regenerated when frosting is noticed.
Follow the procedure below to regenerate the desiccant:

1. Unscrew the brass desiccant container from the rear of the camera and
   remove the O-ring.
2. Plug the resulting hole by screwing in the supplied bolt or plug 2 or 3 turns.
   Finger tight is adequate. Don't put a wrench on it.
3. Heat the desiccant container in an oven at 350°F (175 deg C) for 4 hours. The
   solder used to seal the can melts at 460 degrees F, so be sure to stay at least 50
   degrees below this number. Preheating the oven to avoid hot spots is
   advised.
4. Replace the desiccant container into the rear of the camera, being careful to
   reinstall the O-ring and insure that it does not get pinched.
5. Expect the camera to take an hour or two to reach the frost free state. If it
   does seem to frost and you need to capture images, reduce your cooling to
   the zero degree C range - the CCD dark current will still be quite low.

A noi i sali Sbig, dopo la rigenerazione, sono durati Natale e Santo Stefano, sarà stata la location veramente umida in cui usavamo la ST7? Può darsi.