View Full Version : DFK41 problem

March 12, 2010, 17:19:36
I just got my DFK41AU02.AS camera. I tried it out last night and noticed two odd problems.

1. The image only appears when very near the proper focus. If I move away from focus, the image quickly darkens and disappears. I have never noticed this with any other camera or webcam I have tried with my telescope. I have a Celestron CPC1100 telescope and had the camera at prime focus.

2. I tried it on Mars, and the image looked horrible. It had vertical lines in it. I wonder if this has something to do with pixel size or if I just had the settings wrong. In the photo, the one on the left was taken with my DFK, the other two taken with other cameras.


Thank you very much

Stefan Geissler
March 15, 2010, 10:06:12
Hello Darwin-T,

unfortunatelly I can not say anything about the focussing. I am very sorry for this. You may ask your telescope manufacturer for help too?

The grayscale image you see is the Bayer raw data from the CCD. You used the Y800 video format in order to receive the bayer raw data, right? Thus the colors must be calculated by a debayering program. You may have a look here: http://www.astronomycamerasblog.com/2008/05/16/colored-raw-data-uncompressed-y800-capture-registax-import/

However, if you make single images, you may use the BY8 or UYVY video format instead of Y800.

March 17, 2010, 00:07:04
Thank you Stefan.

I am now trying YUY2 and am accepting the lower frame rate. My main use for this will be photographing the ISS, then the Moon and then some planets. I'm going to do some more testing tonight if it doesn't get cloudy.

I am very impressed with the IC Capture program. It looks like one can change the brightness, etc even while it is recording a video.

I was also surprised to find that the camera supports ROI, because I saw no mention of it anywhere.

Stefan Geissler
March 17, 2010, 11:29:04

The ROI is only a software ROI. It is not done on the CCD.

The higher frame rates can be achieved, if you use the BY8 video format.

March 22, 2010, 15:19:00
I thought I'd post my first results with my new DFK camera. I'm pretty happy with them.


Thanks for the help.