The default gains have been revised to reflect this improvement (see Sec. 3.1.1); sticking with the default gains will generally make you happy.
| CCD | Default Gain | electrons | 0.1% linearity | 1.0% linearity |
|---|---|---|---|---|
| (electrons/ADU) | @65K ADU | (electrons) | (electrons) | |
| Cryocam | 0.8 | 52,000 | 150,000 | 160,000 |
| F3KB | 2.3 | 149,500 | 170,000 | 190,000 |
| GoldCam | 1.4 | 91,000 | 80,000 | 80,000 |
| S2KA | 2.5 | 162,500 | 145,000 | 160,000 |
| S2KB | 2.8 | 182,000 | 210,000 | 230,000 |
| T5HC | 3.2 | 208,000 | 420,000 | 450,000 |
| T2KA | 3.6 | 234,000 | 180,000 | 190,000 |
| T2KB | 3.1 | 201,500 | 220,000 | 250,000 |
| T2KC | 1.7 | 110,500 | 190,000 | 200,000 |
| T1KA | 3.0 | 195,500 | 250,000 | 250,000 |
The electronics has also been readjusted to minimize the effects of overshooting for these new default gain settings for the chips used for direct imaging; users who are concerned with the effects of very saturated stars on their imaging data should stick with these default gains to minimize the effect. Spectroscopists should be unaffected by this problem.
Because these A-to-D converters are also faster than the old ones, the read-down times of all of our chips are now shorter. For every 2048 x 2048 image you take, you will realize a savings of some 16 seconds. While this may not sound like much, it translates to an hour or more per night spread among the various Kitt Peak telescopes; over the course of a year, we estimate that this should save about 5-10 nights worth of telescope time in read-out time alone!