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pieter
March 1, 2010, 09:58:32
Hello,

The DMK 21AU04 is specified with a dynamic range of the ADC: 10 bit, output: 8 bit.

I noticed there is a AD9895 chip mounted on the lowest pcb, which has a 12 bit A/D converter inside.

Is it possible to get the full 12 bit dynamic range instead of 8 bit?

Best regards,

Pieter

Stefan Geissler
March 1, 2010, 10:32:07
Hello Pieter,

No, not possible in the USB and FireWire cameras right now. The GigE camera have 10 bit output. BTW, what software do you use, that can handle 10 / 12 or 16 bit grayscale images?

pieter
March 1, 2010, 10:45:04
Hello Stefan,

I haven't got software to handle this data (yet), but I was wondering why the camera doesn't use the remaining 4 bits of the ADC.

BTW, how do you get from 12 bit to 8 bit? Is this handled by the firmware inside the Blackfin processor?

Best regards,

Pieter

Stefan Geissler
March 1, 2010, 10:51:36
Hello Pieter,

Well, if there is no suitable software for handling these formats, then there is no reason, why to export them. I am not allowed to publish, how the a/d handling is done in the firmware.

However: 10 bit output is interesting for stacking of images only. In single images the additional two bits are only noise. But if a few hundred images are stacked, then there may is usable information in. Only a good algorithm is necessary to map the available 10 bits to the computers / graphics boards 8 bit display.

pieter
March 1, 2010, 11:20:25
Hello Stefan,

Surely good algorithms and software are needed, but I first want to know if the hardware is up to the job.

The last bits will be more noisy, sure, but you are talking about a 10-bit output, while there is a 12 bit ADC inside.
Are all remaining 4 bits, noise-bits?

What software is used with the GigE camera's to cope with the 10 bit output?

Best regards,

Pieter

Stefan Geissler
March 1, 2010, 11:22:59
Pieter,


The last bits will be more noisy, sure, but you are talking about a 10-bit output, while there is a 12 bit ADC inside.
Are all remaining 4 bits, noise-bits?
Good question that I wont discuss in public.


What software is used with the GigE camera's to cope with the 10 bit output?
Right now there is none. There is a NASA image format for 16bit gray scale. And the Lucam Recorder will support 10 gray scale in future.

pieter
March 1, 2010, 12:18:36
Stefan,


Pieter,


Good question that I wont discuss in public.



Can this be discussed offline? (by email perhaps?)



Right now there is none. There is a NASA image format for 16bit gray scale. And the Lucam Recorder will support 10 gray scale in future.

Ok, so the GigE camera's also use IC Capture?

Stefan Geissler
March 1, 2010, 13:17:25
Pieter


Can this be discussed offline? (by email perhaps?)
Even this is kind of public. It is confidential internal content.


Ok, so the GigE camera's also use IC Capture?
Right.

oliver_p
March 2, 2010, 12:24:28
Hello Stefan,

Pieter,
Good question that I wont discuss in public.

Hm, we know the full well capacity of the CCDs and we can assume the level of noise so we can tell the max. usefull bit depth, what's so secret about that?
I doubt that more than 10Bits make sense for the ICX098BL e.g.

Best regards,
Oliver

Stefan Geissler
March 2, 2010, 13:39:43
Oliver,

what is secret is electronics and firmware.