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Old 20-03-2015, 09:44 AM
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floastro
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Join Date: Aug 2007
Location: Pithiviers-Le-Vieil, France
Posts: 81
Hi Greg, hi all,

Just received this reply from Moravian. My 2 questions were information about the KAF-6303 problem dectected in 2013, and why their Moravian G3-16000 with the KAI-16070 CCD chip based was out of their list since late in february.

This is their reply with all information :

" Dear Mr. Poiget,

Thank you for your interest in our CCD cameras. Apparently a few years ago the production of KAF-6303E changed somewhat. Possible redesign lead to introduction of the charge trap in the CCD output node. This charge trap causes smearing of bright pixels (leaving somewhat higher signal in the pixels following bright pixels as the charge is released from the trap. OnSemi agreed this is a manufacturing fault and promised to solve this issue, but we are still waiting to the solution. Unfortunately this effect is visible only if very low noise electronics is used, which is not the case of OnSemi test board and some competing cameras.

The G3-16000 camera shipment is also on hold now because of horizontal charge transfer efficiency problem inherent to KAI-16070 CCDs. The CCD cannot perform horizontal transfer with good enough efficiency and our electronics is so low-noise that it shows the problem. We can only guess the reason is the KAI-16070 architecture, allowing simultaneous read from 4 outputs (astronomical cameras use single output either way). For now, the G3-16000 camera is on hold, OnSemi (former Kodak) obviously cannot do anything with it (their own test electronics digitize to 12 bits only and they do not want to invest into fixing of the CCD to be useable with very low noise 16 bit electronics).

These two detectors are the only problematic. Other detectors work flawlessly, especially the KAF-16803, used in G4-16000, produce superior image with very low noise and uniform field of view without artifacts. See the gallery on the bottom of the http://www.gxccd.com/art?id=383&lang=409 page, please. I believe ASA Wynne 3" coma-corrector can cover the KAF-16803 CCD, providing you have large enough secondary mirror.
"


Best Regards,

Florent
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