
The photometric camera G2-1000BI (Moravian Instruments) with E2V CCD 47-10 chip is installed in the primary focus. The focal length of the main mirror is 9 m (focal ratio f/4.5), but the correcting lens changes the effective focal length in primary focus to 7 m (focal ratio to f/3.5). The automatic exchange of the instruments between spectroscopic (fibers) and photometric (primary focus camera) configuration can be done within 1 minute. The camera is equipped with five position rotating filter wheel with different filters and cooled up electronically (down to -40° C under ambient) by Peltier cell.
Camera and chip
ADC | Resolution | Pixel size | Read. noise | Efficiency | Linearity | Reading |
16 bit
|
1056 x 1027
|
13 x 13 μm
|
9 ADU
|
90% (500-700 nm) |
> 95 %
|
10 s
|
Camera and telescope
Effective focal length | Field of view | Angular resolution | Test image |
7 000 mm | 6.3′ x 6.3′ | 0.385 “/pixel |
![]() |
Photometric filters
The camera is equipped with five position rotating filter wheel with different filters. Complete list of available filters: Sloan u’, Sloan g’, Sloan r’, Sloan i’, Sloan z’, H-alpha, [O-III], [S-II], Bessel B, Bessel V, Bessel R, Bessel I. Narrow band filters have bandpass width 3 nm.
Currently installed filters (see the table).
Position | 0 | 1 | 2 | 3 | 4 |
Filter | O III | i’ (SSDS) | r’ (SSDS) | g’ (SSDS) | Hα |
Camera and telescope performance (in good seeing conditions)
brightness exposure filter measurement error Χ ~ 12.5 mag 8 s r' ~ 0.002 mag ~ 1,05 ~ 15.2 mag 8 s r' ~ 0.006 mag ~ 1,10 ~ 16.2 mag 10 s g' ~ 0.020 mag ~ 2,20 ~ 18.3 mag 20 s g' ~ 0.030 mag ~ 1,10 ~ 23.3 mag 7 h r' ~ 0.160 mag ~ 1,40
