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Old 22-09-2009, 09:46 AM
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multiweb (Marc)
ze frogginator

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Join Date: Oct 2007
Location: Sydney
Posts: 22,060
Quote:
Originally Posted by toryglen-boy View Post
i was putting the CCD and MPCC in a clear plastic bag, filling the bag with warm air from a hairdryer, and throwing a few bags of silica gel in there, and then assembling the whole lot, with the bag tied shut
That'll work nicely although you don't have to go to that extreme unless you do this outdors, then yes the bag trick is good.

I usually assemble indoors. Hold the camera without the nose piece face down then blow air up in it (warm - not hot). Do the same for the spacer and MPCC in the cavity then quickly assemble them.

One thing I did too was to tape all around the body of the QHY8 with black electrical tape to "seal" it. Both from light leaks and air. Also siliconed around the power/USB plugs. I also recently got some silica gel strips from Theo to stick on the walls of the spacer but I haven't had any problem so I didn't use them as yet.

One thing to keep in mind is the orientation of your camera too. If it points down the cold air will fall on to any glass surface at some point and you will fog up. So just look for that when you choose your target to image or side of the meridian.

Learnt that the hard way when shooting flats with my 67mm pentax lens and I sat the QHY8 face down on my EL sheet First two 0.5s flats were fine. Took less than a second to fogup the lens.
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