A: Dtec, ctype(Phot) + conductor = sprk(conductor)
B: Pscn+Nscn= Solar panel. (Phot) + (Pscn&Nscn) = sprk(conductor)
Method B absorb's the PHOT. Method A detect's the presense of a PHOT.
In both cases, a PHOT moving too fast can fly through/past the detector.
Glow will generate more photons if some of them get inside it. You need to have large amount of GLOW to keep the reaction or build walls around it.
An interesting one, requires a 3+ elements though:
1. Pass the PHOT through about 2 layers of INVS, to turn it to NEUT
2. Have the neut pass through a large amount of glass, which generates more PHOT
3. Have a seal around it, made of something like FILT, to keep the photons out and the neutrons in
I found out about this a couple years back, Idk if anyone else had, but basically if you design it right you can make a really cool-looking device that generates infinite photons and neutrons with a nice blue glow (unless pressure gets too high and the glass breaks).