System - photometric camera in primary focus, coude spectrographs fed from primary focus by optical fibers.

Telescope

In operation: since 1967

Mounting: equatorial (special, author Alfred Jensch, Carl Zeiss)

Primary mirror: diameter 2.0m (general diameter 2.08m), thick 30cm, weight 2340kg. Parabolical. Focal ratio 1:4.5

Focal ratio: 1:4.5 in primary, effective 1:32 in coude

Photometric camera: We operate photometric camera installed in the primary focus.

Camera: G2 MarkII 3200 (Moravian instruments)

CCD chip: KAF-3200ME, 2252x1544, pixelsize 6.8x6.8 microns

Readout noise: 9 ADU

Gain: 0.93

Cooling: Peltier

Effective focal length: 700cm

Field of view: 7x5 arcminutes

Resolution: 0.2arcsec / px

Filters: u', g', r', i', z'

The focal length in primary focus is 9m (focal ratio 1:4.5) but the photometric camera changes the effective focal length in primary focus to 7m and focal ratio to 1:3.5

Spectrographs:

There are two spectrographs installed in (original) coude focus. After the upgrade of the system (2018-2019) theyr are fed by optical fibers from primary focus.

The skipping between fibers (i.e. spectrographs) and photometric camera is withing 1 minute.

Guiding camera:

Camera: G1 0300 (Moravian instruments)

Filters: No filters

Exposure time: 0.1 -- 30s

Field of view: 7.1 x 5.3 arcmin

Limit magnitude: 17.2mag

Scale: 0.64arcsec/px

Single order spectrograph:

Spectral orders: 1 and 2

2. order 4000 - 5100 angstroms (near UV and blue)
Order length in 2.order: 233 angstroms

1. order 5100 - 9000 angstroms (red and near IR).
Order length in 1.order: 470 angstroms

Resolving power: 12000 in Halpha

CCD chip: PyLoN 2048x512B, pixel 13.5 micrometers

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Echelle spectrograph:

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Resolving power: 40000 in Halpha

CCD chip: EEV 2048x2048, pixel 13.5 micrometers

Spectral orders: from 80 (near UV) to 130 (near IR) angstroms

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Fiber:

There are optical fibers connecting primary focus to spectrographs which are installed in the (former) coude focus:

CeramOptec,

octagonal,

active core diameter 0.1mm

There are two fibers to single order spectrograph, one for stellar light and other for sky background.

One fiber is to the echellet. Individual spectral orders are close to each other and there is no space for the background. Also, we don't subtract scattered sky light from echellograms.

Two devices are installed in the primary focus: input to optical fibers and the photometric camera. Both devices are held in the "train" which can insert one or other device to the primary focus.

The input to the optical fibers is also used for the guiding the telescope. The fibers are inserted in sloped mirror in the focus of the guiding camera. The "train" can shift first, second or third input to the position of the primary focus (and into the total reflection of the mirror - guiding mirror system). The mirror is not of high quality because we just need to get proper picture for the guiding.

Photometric Camera

Spectrographs:

Guiding System for Spectrographs

Echelle Spectrograph Technical Specification + atlas of ThAr lines

Single Order Spectrograph Technical Specification + atlas of ThAr lines

Our meteostation - Weather monitoring

Fisheye - Sky monitoring

Diesel power supply - backup source