Web Cam sensitivity

Does anyone know if the Toucam's lose "sensitivity" over time. By that, I mean last night when I was trying to image the moon, I had the 9.25" at F/20 and not only did I have to set exposure to 1/25 sec, but brightness to about 80% or so. I don't remember having to do this 6 months ago. I was imaging along the terminator, but even when I moved a little more into the "moonlight", the image seemed a bit dim. I was using a NIR filter, but nothing else. I have another Toucam 740 new in the box and was thinking of trying it out as a test. I was just wondering if anyone has seen anything like that. I've had the webcam since June 2003 and have used it quite a bit, lately for solar imaging.

Thanks!!
Paul Maxson

Paul,

I think the color mosaic filters on the chip can fade over time if exposed to high ambient light levels. But, this effect is small and actually just "washes out" the color.
I have a similar setup and if you're at F20 and using 1/25 and a gain of 80% something is wrong. typically, I use 1/250 Sec to 1/500 Sec and very low gains at F25.