Thread: CCD tilt
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Old 06-10-2012, 07:33 PM
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Shiraz (Ray)
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Location: ardrossan south australia
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well I guess that is the main problem then - the measure from the front face of the camera case to the chip surface should be the same at all points on the chip (within about 30microns or so).

I can't think how the chip could be as much as 3mm out of alignment - that is an extraordinary offset - mine was 0.3mm and even that was pretty bad. It's a while since I did mine, but from memory the aluminium chip carrier+plate is in close (thermal paste) contact with the TEC, the TEC mates up against the heat sink and the heatsink bolts onto the camera body - can't think how anything could be 3mm out, unless the chip carrier is not fully in contact with the TEC or the TEC has come away from the heatsink?? If that is the case though, putting the camera back together should force them all back into contact. Definitely worth another look to see why it is that far out - you may even be able to see what is going on without dis-assembly if its that far out. Shimming will help, but will decrease cooling effectiveness. Maybe do a trawl on the QHY forums and also ask if anyone there knows what could be going on - Theo in particular knows these cameras well. there are also some threads that discuss the structure of the camera, but if you have already had it in bits, you have probably seen some of them.

haven't tried the artificial stars, but they should be OK if you have a long enough free path (probably need about 50m or so with that scope)

all the best Ray.

Last edited by Shiraz; 06-10-2012 at 09:44 PM.
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