Right I'm putting a pot on the input to adjust the "gain". (photons per volt.)
I'm mostly working by myself.. no real electronics people to bounce ideas off of. It's weird how you can get stuck in some design path.. know it's not good... (see my original schematic.) But not see the way clear, until someone gives you a head slap.
Thank God for SEB and SED.
George H. (being agnostic, I think I'm still allowed to thank God for stuff. :^)