Since Ogre. brought up the subject of 20 sec photons over on rebangs it got me thinking. (scary and unusual)
At first I was amused at the length, 20 secs is like 20 times longer than really needed to use a photon.  I mean, you set up a whole macro to do the photon, maybe xport into your invasion ship, warp in, land on planet whatever.  This is what I guess I think of when I think of photon time. 
However, isn't that also the amount of time to reload and photon again?  If multiple photons are disabled, doesn't the torper hafta wait for the wave to finish before they can fire again?  So a gridder wanting to work without a photon threat could do quick burst to trigger a photon shot, hopefully missing, then go whoohooo for like 19 sec. before the torper could reload.
Am I wrong on this? 
Also, if multiple photons are enabled, is there a 'max' time that a sector could be photoned? My experience is even more pitiful here, dosen't each photon 'stack up' on the previous? Adding time onto the first photon wave in this way, where do you start counting?  Do you have to wait for 19 secs and then photon again?  or can you shoot 10 photons and in this case have 200 sec of photon?
 
So I'm still a newb, seekin' guidance...
 
 
 

Yea, w/o multiples you have to wait. So 20 second photons mean you have to make your shots count. Of course that's realllly easy to adapt to, just target runs instead. Photons only stack when multiples are on. But then yea you could fire quite a few and get a nasty wave built up if that's what you're going for.