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Levente
May 7, 2009, 11:23:26
We have a problem with a Dbk.31.au03.as camera: the image is rasterized especially in the right part of the image, see attachment. Is it a software setting error or some kind of a defect in the camera?

Stefan Geissler
May 7, 2009, 17:38:52
Hi Levent,

you see the raw data image. You may use programs like Registax for debayering. You may look here too:
http://www.astronomycamerasblog.com/2008/05/16/colored-raw-data-uncompressed-y800-capture-registax-import/


(This rastered image issue has been discussed quite often in this forum....)

Levente
May 7, 2009, 19:07:59
Stefan, did you notice that only the bottom right corner shows the Bayer-Pattern? Is it possible to debayer ony PART of an image?

Stefan Geissler
May 8, 2009, 09:06:46
Leven, no i did not. Please attach the images as BMP (may be in a Zip file), thus the Jpeg compression does not disturb the image. Thank you.

Levente
May 8, 2009, 11:07:24
Stefan, the image would be too large to upload (2M) so you can download or look at it from here:
http://www.makszutov.hu/download/aris.bmp -or-
http://www.makszutov.hu/download/aris.zip

Image is stacked with Registax V5. (Registax v4 has the same problem.)

Thank you for investigating the problem.

Stefan Geissler
May 8, 2009, 11:38:01
Levente, I see, the raster is only visible in the right side, starting somewhere in the middle of the image. It can be a result of the used debayering algorithm (you may refer to http://scien.stanford.edu/class/psych221/projects/99/tingchen/main.htm).

May be you specified the wrong debayering pattern?

Is is possible, to send me one of the original images provided by the camera?

Levente
May 8, 2009, 15:23:21
Unfortunately, i cannot send you the original images as they are captured in an uncompressed UYVY format avi that is 2 g.

We will try to record using Y800 codec and debayer with registax as described here: http://www.astronomycamerasblog.com/2008/05/16/colored-raw-data-uncompressed-y800-capture-registax-import/

Please note, the guy who made the last comment here has similar problem, but his question remained unanswered ...

Stefan Geissler
May 8, 2009, 15:27:05
Well, uncompressed YUV is no raw data, even if it is saved with an Y800 codec. This should result in a nice greyscale image.

Levente
May 8, 2009, 15:39:01
I'll request for detailed and exact information about the video record settings from my customer and will forward to you.

Have a nice weekend, Stefan!

Levente
May 11, 2009, 15:06:30
Stefan, I was told no matter what codec my customer used the bayer mask was visible. If he rotated the camera the artifact rotated as well. I'll try another camera to see where the problem is and will probably send the camera back for replacement.

Stefan Geissler
May 12, 2009, 09:52:19
Hi Levente,

however, I need one of the original 8 bit images. I assume, your customer used the wrong bayer start pattern in registax. This is the only reason I found for nearly correct colors, but visible bayer pattern on positions, where the blue, red and green light are not of the same brightness.

Levente
May 12, 2009, 20:51:27
Hello Stefan,

I made two pictures indoor:
http://www.makszutov.hu/download/snap_yuv2.bmp
http://www.makszutov.hu/download/snap_y800.bmp

If they are not suitable, please let me know the settings and details I need to set for making sample images for evaluating the problem.

Stefan Geissler
May 13, 2009, 09:34:31
Hi Levente,

the images are correct. You see the typical Debayer edge sensing algorithm pattern on the homogeneous planes. This is absolutely not the phenomenon that your customer sees.

I guess your customer uses some strange settings either in IC Capture or in Registax. As I already wrote, I need one of the original Y800 BMP images, the customers used. As far as I know, Registax can export single images from an AVI file.

Levente
May 27, 2009, 13:08:43
Hi Stefan,

We have still been struggling with this "debayer"-like artifact. My customer recorded a Saturn image and some weird pattern is visible (one frame): http://www.makszutov.hu/download/saturn_artifact.jpg

He also sent me the screen shot of the recording dialog: http://www.makszutov.hu/download/saturn_settings.jpg

Is he doing the recording in a wrong way?

Thanks,
Levente

Stefan Geissler
May 27, 2009, 14:59:44
Hello Levente,

the resulting image is absolutely correct. The user used "BY8" video format, but from the button settings I can see, that Debayering, that means raw data to color transformation, is disabled. Then the raw data images from the CCD are saved to the RGB24 file.

This is what he sees. If he want colorred RGB24, he should not disable the Debayering in IC Capture in order to get raw data.

If he wants to dabayer later, not in IC Capture, he nearly did the correct things. I would not use RGB24 but Y800 for AVI Capture instead.

Levente
May 27, 2009, 16:41:01
Stefan, thank you for the reply. How can we capture _monochrome_ avi using IC Capture?

Sorry for the lots of questions, but my customer doesn't speak english and I need to interact for him and sometimes I don't get what he wants ....

Stefan Geissler
May 27, 2009, 17:27:16
Hi Levente,

Please have a look at this nice tutorial:
http://www.astronomycamerasblog.com/2008/05/16/colored-raw-data-uncompressed-y800-capture-registax-import/

Levente
June 8, 2009, 13:26:11
Stefan,

We carefully investigated the case, used another very same The Imaging Source camera and seems the weird pattern is "created" by my customer's camera. (The other camera doesn't produce this kind of artifact.)

Please take a look at this Moon shot: this is an unprocessed frame that shows the lines that are more pronounced in the right part: http://www.makszutov.hu/download/moon_showing_pattern.bmp

I'm going to send the camera back for replacement.

Thanks for your help, anyway.

Levente

Stefan Geissler
June 8, 2009, 14:36:57
Dear Levente,

Thank you for the image. Again, I got no original image from the camera, only what is shown in a third party program. And also I do not know, which settings you used in IC Capture. Did you follow the tutorial I mentioned in my last post?
What camera was in use? Please excuse me asking so much.

Levente
June 8, 2009, 17:42:18
Hello Stefan,

I really appreciate your efforts to help me, but we are pretty sure there must be something wrong with the camera. (Remember, the same camera with the same settings produced artifact-free image!)

I can specify your name and address when I return the camera so that you can investigate the case further with the camera in your hands.

Thanks,
Levente

Stefan Geissler
June 8, 2009, 17:58:49
Good idea.