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Celestman
October 18, 2012, 02:26:44
Hi everyone,
I hope someone can advise me regarding the colour balance of my DBK618. I am using the camera with a Baader UV/IR cut off filter but my images are too red in colour. I have switched off the auto white balance and tried to reduce the red slider and adjust the blue ( and why is the green slider ghosted out? ) but Jupiter is still being imaged with a red cast. Can someone advise me on what settings I should be using to give a natural colour to Jupiter. It`s driving me nuts!

Many thanks,
Ralph

Stefan Geissler
October 18, 2012, 08:33:32
Ralph,

I do not know, why the image is so red, this is a question, an astronomer can answer much better than me. Do you see the reddish images in IC Capture or in postprocessing? If you use Y800 video format and the image is more pink than red, then you may use the wrong bayer pattern for debayering.

The green slider is inactive, because the camera has no white balance green property. Only supported properties have activated controls.

Celestman
October 18, 2012, 11:25:27
Thanks for the reply Stefan. I see the red colour both with IC Capture and in post processing when using the YUY2 setting and unspecified codec. What is the correct Bayer pattern for debayering?

Many thanks,
Ralph

Stefan Geissler
October 19, 2012, 10:59:58
Hello,

The YUY2 format should not be used in combination with unspecified codec. Please use Y800 video format instead.

In postprocessing, simply try all four bayer patterns until you get a good result: no "pixelization", not pink or greenish.

Celestman
October 19, 2012, 13:00:13
Hello,

The YUY2 format should not be used in combination with unspecified codec. Please use Y800 video format instead.

In postprocessing, simply try all four bayer patterns until you get a good result: no "pixelization", not pink or greenish.



Thanks Stefan. What is the best codec to use with YUY2 format? Will try your other recommendation with respect to the Y800 format.

Best regards,
Ralph

Stefan Geissler
October 22, 2012, 09:28:55
The best codec for YUY2 would be RGB24 and RGB32. YUY2 already is colored, that means debayered. Therefore, a Y800 codec would save a grayscale image without any color information only, because the color information is transformed into grayscale.
Using Y800 as video format in the camera and Y800 as codec needs now colorspace transformation, because the input and output formats are the same. Since Y800 is rawdate from the sensor, it contains the color information in the bayer pattern, so a saved Y800 codec AVI file can be debayered by e.g. Registax.

flyer
January 12, 2013, 12:24:08
I realize that this is an old thread, but others may find this information useful. I use the same camera (DBK21AU618) and do not have a color issue if I follow these steps:

1. turn on debayering so that you can view the image in color (assuming the capture is Y800)

2. Turn on the histogram

3. Adjust the Red and Blue sliders until the right side of the histogram shows equal values for RGB

4. Adjust the gain such that there is 20+% margin before clipping on the right side of the histogram.

5. At this point the color should look quite realistic. If it doesn't don't bother capturing because the captured result will be quite similar.

6. If capturing Y800 you must turn off debayering. The histogram will now only show gray scale.

7. The Y800 video must be debayered to give proper color. There is much confusion about this, particularly if the ROI option was used!

8. If ROI has been used then you must experiment to determine the correct debayer pattern. There is no way for any software to know what the correct pattern is. Whilst the camera CCD may say the pattern is such and such, once the ROI has been utilized the pattern can/will change depending on the image size chosen. If you use the debayer tool in FireCapture it is easy to just select the different patterns to see which pattern looks correct. This is also true for Autostakert. There is a good plugin for debayering in VirtualDub but unfortunately it does not allow the user to select the debayer pattern and sometimes makes a mistake. However, that problem can be fixed in photoshop by copying and pasting the colors into the correct channels.