Dome (screen) Flat Fields : "Flatf. Pos." from the Telescope's GUI + "ffl" software:
CCD frame definition: full_frame_slow_bin2
| ffl lamp | exposure time (seconds) | channel 1 (counts) | channel 2 (counts) | channel 3 (counts) | channel 4 (counts) |
|---|---|---|---|---|---|
| 150 W 1000 W 1000 W 2000 W |
3.0 1.5 3.0 / 12 30 |
u - - - 30000 |
b - - 28000 / 30000 - |
y - 30000 - - |
I 30000 - - - |
| 1000 W |
15 |
- |
Hbeta(narrow) 35000 |
- |
- |
| 1000 W |
3.0 |
- |
Hbeta(wide) 35000 |
- |
- |
March 2004
| ffl lamp | exposure time (seconds) | channel 1 (counts) | channel 2 (counts) | channel 3 (counts) | channel 4 (counts) |
|---|---|---|---|---|---|
| 150 W 150 W 150 W 150 W 150 W 300 W |
1.5 2 2.5 3.5 30 5 |
UV_B 2200 2800 3400 4500 34000 38000 |
B_B 13000 18000 22000 31000 saturated saturated |
R_B 25000 34000 42000 saturated saturated saturated |
NIR_B 34000 45000 56000 saturated saturated saturated |
| 150 W 150 W 1000 W 1000 W 1000 W |
2 2.5 0.3 11 12 |
v - - - 23000 25000 |
b - - - 33000 35000 |
y - - - 36000 39000 |
I 29000 37000 36000 saturated saturated |
| 3450 W |
10 |
u 27000 |
Hbeta(narrow) 33000 |
|
|
| 1000 W |
7 |
|
Hbeta(wide) 34000 |
|
|
Saturation begins at ~ 65000 counts, which is shown on the View Control of the GUI with red color (using the defaults image cuts).
FLUSH THE CCD's with the large button labeled Flush CCD AFTER TO REACH SATURATION LEVEL.
There is a special UV lamp to take good dome flat field in uv channel (ask the staff). If you are using this device, please, take into account that it is necessary to wait about 2 min to get the lamp warm, and if you turn off, also it is necessary to wait at least 6 min if you want to turn on again.