Shutter

The shutter accuracy has been calibrated, and a shutter delay of 0.07 sec was found. The calibration data was re-obtained several times as there were difficulties with jumps in the dark levels and possible variations in the calibration lamp. The estimated shutter delay will be implemented in the NOTCam BIAS. The accuracy should then be 1% down to 0.6 sec exposure time. Shorter exposure times are not reliable. Currently, the accuracy is $\sim$3% for exposure times of 2 sec and $\sim$1% for exposure times greater than 3 sec. In general, exposure times are greater than 3.6 sec.