In 2009 Konkoly Observatory had initiated a project on designing an instrument that capable to aquisit high angular resolution observations such as speckle imaging and lucky imaging. The system based on a modern Electron Multiplying CCD (EMCCD) camera. In order to maintain its optimal operation a temperature controlled camera housing and filter wheel unit were designed. The camera, housing and filter wheel is designed to be controlled by a single linux based control system. I was assigned to design and implement the control system.
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CAMERA Andor’s iXon 888 is megapixel back-illuminated EMCCD, combining large field of view, single photon detection capability and > 90% QE. The 1024x1024 frame transfer format offers unequalled thermoelectric cooling down to -95°C (with water cooler applied) and industry-lowest clock induced charge noise. EMCCD and conventional CCD readout modes provide heightened application flexibility. The iXon 888 benefits from an advanced set of user–requested features, including OptAcquire, Count Convert, Spurious Noise Filters, Cropped Sensor Mode, Signal Averaging and enhanced Photon Counting capability. Patented EMCALTM and RealGainTM provide sustained quantitative EM gain calibration. (Text from Andor iXON 888 specification sheet.) |
 Andor iXON 888 (UBV) camera.
Andor iXON 888 (UBV) camera. |
| CAMERA HOUSING Own developed housing maintains constant ambient temperature (± 0.2°C) and low humidity for the camera required for precise measurements. Two heater is installed inside the housing. The high power heating transistors maintains the temperature outside the camera own housing. A low power heating transistor maintains the temperature above the camera window to avoid unwanted vapour deposit. In order to be able to control the temperature inside the housing by fan, the inside temperature is always heated above the ambient temperature. The housing was developed by Konkoly Observatory (electronic design by László Döbrentei, mechanic design by Miklós Rácz). |
 Camera Housing.
Camera Housing. |
| FILTER WHEEL Own developed filter wheel stores 12 filters. The unit contains two filters, each of them can store 5 filters (one filter place must be empty to clear light pass). The unit is capable to change any filters within 5 second. The housing was developed by Konkoly Observatory (electronic design by László Döbrentei, mechanic design by Miklós Rácz). |
 Filter Wheel.
Filter Wheel. |
CONTROL SOFTWARE All instruments is controlled by a server application running on Linux operating system. All units (camera housing, filter wheel, camera) can be controlled by sending commands via standard telnet protocol. The easy to use client GUI (native wxWidget based for Linux and Mac OSX platforms) communicates via network sockets with the server. The software is capable to control the camera (set image region of interest, conventional/EM CCD modes, gain control, exposure time setting, focusing guidance), the housing (heating settings, fan control), and the filter wheel. With this software the observer are able to initiate observational runs that incorporates multiple images taken with multiple filters. |
 iXON GUI Software.
iXON GUI Software (native OSX) |
