View Full Version : Y800 and debayering problems - some useful tips?

May 6, 2016, 22:40:26

Having spent most of the day wrestling, I've finally solved (with some help from Stefan) how to record planetary videos in Y800 format using the Skyris 618 with IC Capture, in order to produce smaller AVIs than using RGB32. I thought it would be easy, but my Y800s all came out really blocky, with garish colours in Registax, and bad artefacts. Using RGB32 worked fine, but the AVI files were 3 times bigger.

It's been a bit of a saga so I thought I'd post a summary of how I got it to work, in case it helps anyone else. None of the information seems to be unknown, it's just a pain piecing it all together.

What first alerted me to problems was that the preview display in IC Capture looked like a wire mesh screen had been placed over it when I switched to Y800, and second, the results when I debayered in Registax were a garish mess. My Y800s were unusable - a good still evening's imaging largely wasted...

After a lot of forum-searching and experimentation, I think the basic guidelines for success can be summarised as follows:

1) The colour balance controls in IC Capture Device Properties apparently need to be set manually to 128, 128, 128 or 64, 64, 64 for the Skyris 618 when using Y800, otherwise you can get garish colours when debayering. In other words, sort the colour balance later.

2) Remember to select Y800 from the drop-down and "Unspecified" for the codec in the AVI controls

3) Be aware that the Y800 AVI header produced by the IS cameras is wrong (there is a thread about this at 324269-Debayering-Still-a-bit-confused) and this throws off the debayering tools - see (5)

4) Registax apparently uses a very crude debayering algorithm and I found this resulted in garish colours and bad artefacts, so I do not use the prefilter in Registax but instead use another tool such as PIPP or the utility with FireCapture to debayer the video first

5) Whatever debayering tool is used, note that although the AVI is marked as using RGGB, it actually needs BGGR to debayer it correctly

6) Having exported a debayered AVI from PIPP I found that the resultant colour video could then be aligned by Registax with good results

Useful links:

Hope this helps - and apologies if it's reiterating what everyone but me knew already!