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[1ponders]
May 16, 2007, 10:35:05
Could someone please tell me the approximate pixel well depth please?

Stefan Geissler
May 18, 2007, 16:13:59
The 21AF04.AS is equipped with a the Sony CCD ICX098BL. You can download its specification here...

http://www.astronomycameras.com/en/products/firewire-cameras/mono/dmk21af04as/

...but unfortunately Sony does not provide the well depth of their CCD's pixels.

[1ponders]
May 19, 2007, 00:38:44
I know, it's a pitb really. I was hoping someon here has done a measurement.

Oh well.:)

marsel60
June 2, 2007, 10:43:05
Hello folks,
I am interest too in this kind of CCD specification and sailing around in Internet I found an interesting link that shows more CCD specification.
It is:

http://theta-system.com/icam.htm

You can found some CCD specification like Full well capacity, Dark current and so on. I hope that specification can be assumed for ALL Sony ICX204AL that are used also in TIS cameras.
Hope this help.

[1ponders]
June 2, 2007, 10:54:28
Thanks Marsel :)

JMZawodny
June 19, 2007, 22:45:43
I just did a well depth measurement vs gain setting for the DMK 31AF03.AS (see attachment). At the lowest gain setting the 31 has a full well of around 13,000 electrons. These measurements are pretty easy to make. Anyway the DMK31AF03 has smaller pixels than the 21, so I would expect the 21 to have a full well of between 19k and 20k if the well scales with pixel area.

Joe (new to the group)

marsel60
June 20, 2007, 06:58:33
Thanks Joe for your measurement results. One more question... is it possible to know the procedure you used in order to perform measurements? I am very interested in that. If you think we can continue this discussion via private mail... just let me know. THANKS in advance.
-Marco

JMZawodny
June 20, 2007, 12:10:09
Marco,

Here ( http://clarkvision.com/imagedetail/evaluation-1d2/index.html ) is a link to the procedure. It is very important to use uncompressed images and incandescent light sources. I took a short cut and did not do the linearity measurements. I used the histogram graph to set the exposure to get the brightest image without over exposing. For a simple full well measurement, all you really need is a pair of images taken with the gain at its minimum setting (180). If you can take the images I can do the calculations. The full details on my spread sheet can be found here ( http://flickr.com/photos/jmzawodny/566293142/ )

Joe

marsel60
June 20, 2007, 18:14:41
Joe,
thanks so much for this great update. I am very sorry that you did not perform linearity measurements since I'm very interested on them for DSO and other interesting works on stars. I've build a flatbox for deep images using very brigth white LEDs and I was supposing to perform CCD linearity measurements using it. What do you think about?
Cheers
-Marco