Photon counters were not what I had in mind when you were speaking about astronomy cameras. I remember that around 20 years ago we had 1/100th of magnitude reso

Photon counters were not what I had in mind when you were speaking about astronomy cameras. I remember that around 20 years ago we had 1/100th of magnitude resolution with photon counters compared to 1/10th of the CCDs (SBIG &co.)