The dim images MIGHT be being caused by the level sttings. Firstly let me disclaim by saying I’ve never used a 902H camera for meteor observing. However I have experienced a similar problem in a more professional capacity when I thought I ought to be seeing brighter images than I was.
Before proceeding does the 902H have a small adjuster screw any where? If so, as in my own case, have the camera on and in a fairly dim setting, ALC low, then slowly (and gently, these little pots aren’t meant to be tweaked too many times) adjust the control screw. The level control adjusts the feedback to the iris and if it’s not set properly even in dark dark conditions the iris may not fully open. (resulting in dim images). If this is the same on the 902H then at some point the iris will open fully irrespective of the illumination and you should see a much brighter image. Once you’ve found when it opens the iris take the pot to the end stop in the same direction. This should in effect keep the iris open under all conditions.
I’d use AGC low all the time if the above works, AGC high can be VERY noisy with a fully open IRIS.
Also I’d try “shutter” OFF first. This is related, usually, to the auto shutter settings. On some cameras this shutter really means the electronic exposure. OFF normally defaults to the longest exposure. To test this try it in day light and very quickly it will become apparent if this is the case as the image will saturate out because the shutter speed will not increase.
Hope this helps,
PS Also, some video capture cards seem to automatically produce fairly dim images. You may also need to adjust Brightness/Contrast/Gain on the video control panel. I had two dreadful Hauppauge boards that had this problem, every single power up they had to be adjusted. Thay are now in the bin! I’d try sorting the camera first though….