Hello, I noticed that BIAS exposures show a very strange "illuminated" field, with two bright margins., And, the DARK exposures are saturated within a 1 sec exposure. The 1 sec LIGHT frame looks allright. Please find attached screenshots off all three frame types. This looks puzzeling - any ideas? Thanks in advance for your support. Best wishes, Michael
Please provide a FITS image and also zip up your MaxIm DL settings and upload them (under Documents/MaxIm DL 6/Settings). Make sure RBI preflash is turned off, and that your camera is running the latest firmware and drivers (SBIG Driver Checker).
Hello Doug, please find attached then zipped the MaximDL settings. ANd here is the link to the BIAS FITS-file (it was to big to upload it in the posting) ... http://www.astro-images.de/_originale/STX16803_StrangeBIAS.zip I am using recent SBIG Drivers. Concerning the RBI preflash led - where can I turn it on or off? Best wishes, Michael
The RBI preflash is enabled through the Readout Modes drop list, and also there are some settings in the advanced camera setup. Since you're using 6.13 and the current firmware, given your screen shots and settings it looks to be already off. This looks like it could external light contamination. Were you by chance taking these frames in full sunlight or very bright ambient light? The shutter is not absolutely impenetrable; bright light can leak around the sides and it looks like this might be happening here.
Doug, I am sure that there is no light contamination from outside. And I have checked the shutter movement, here, all looks good. For me, there must be a light source inside the camera, behind the shutter. Please note that the LIGHT frame, even with a covered camera, only produced the low signal level. So there contamination must be inside. Can you please detail the methods to efinitely switch off the RBI preflash? For me there must be a coorelation with a firmare updtae, with older firmware version, the problems havent existed. Best wishes, Michael
If the preflash LEDs are firing improperly, that might be the cause. Please download the latest SBIG Driver Checker version, don't just use the built-in update button. Make sure the firmware is the latest. Make sure the plug-in driver is the latest. And of course make sure you have MaxIm DL 6.13. Now connect MaxIm DL to the camera. Go to the Expose tab and select Options / Camera Settings. Under RBI Preflash click the Default button. Click Close. Now go to the Expose tab, and make sure Readout Mode is set to Raw.
Hello Doug, I have solved the issue. In the SbigDriver Checker firmware tab, I noticed that one of the four files was outdated. version 2.31 imstead of 2.5. When I have done the upgrade, rebooted the cam, the BIAS and DARK exposures look good. So, many thanks for your support. What irritates me, is that this firmware gap caused a led to switch on inside the STX. Best wishes, Michael
Yes you have to update both the firmware and the drivers; otherwise the RBI Preflash feature gets borked. Unfortunately this was unavoidable. The original RBI Preflash implementation wasn't correct, and we had to make many changes to both the firmware and the driver to get it to work properly.
