Regenerating The Desiccant - SBIG STF Series User Manual

B-2 Regenerating the desiccant
This section describes the regeneration procedure for the desiccant used in the
STF cameras. The desiccant absorbs moisture inside the camera body,
lowering the dew point below the operating temperature of the cooled imaging
sensor and thereby preventing the formation of frost.
The desiccant is contained in a small cylindrical container that screws into the
side of the camera chamber. In normal operation, the useful life of the
desiccant is over a year. However, if the camera body is opened often or used
in high humidity conditions, you are advised to regenerate the desiccant every
six months, or even sooner if frosting is noticed.
Note:
When using a domestic oven with self-cleaning capability, please run a self-
cleaning cycle before attempting to recharge the desiccant. Otherwise, the desiccant
could become contaminated.
CAUTION:
Failure to regenerate the desiccant regularly can lead to expensive corrosion
damage inside the camera body and will void your warranty. Do not ignore this
procedure!
To regenerate the desiccant:
1. Place the camera on a clean dry surface with the knurled aluminum
desiccant knob facing upwards.
2. The container screws into the side of the camera body. Use your fingers and
turn it counter-clockwise to extract it.
3. Remove the O-ring from the container and place it aside.
4. Set the camera aside with the container opening facing down. This will
prevent dust from falling into the opening.
5. Heat the desiccant container in an oven at 350° F (175° C) for 4 hours. The
adhesive used to seal the can will melt at very high temperatures, so be
sure to keep the oven temperature below 400° F (205° C). Preheating the
oven to avoid hot spots is advised.
6. Remove the container from the oven when done and as soon as it has
cooled enough to handle. Reinstall the O-ring and insert the container into
the camera. Insure that the O-ring does not get pinched.
7. Turn the container clockwise by hand to tighten it. Do not use tools.
8. The camera may take up to 24 hours to reach a stable frost-free state after
inserting the container. If you need to capture images prior to this time and
it frosts again, reduce your cooling to the 0° C range - the dark current will
still be quite low.
Additional desiccant plugs are available from Diffraction Limited.
SBIG STF SERIES - CAMERA USER'S MANUAL
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