The new EMCCD all-sky imaging spectroradiometer at SGO Carl-Fredrik Enell 1, Tero Raita 1, Sanna Mäkinen 2, Noora Partamies 2, Mikko Syrjäsuo 2, Kirsti Kauristie 2 2 Finnish Meteorological Institute, Helsinki Second NordAuropt workshop, Tromsø, April 2008
Outline 1 Imager details 2 Experience 3 Questions
Outline 1 Imager details 2 Experience 3 Questions
Keo Scientific Ltd. imager Imager identical to FMI system Andor ixon+ DU-888 camera head SmartMotor filter wheel stepper (RS-232) Athena XT16 temperature controller
The electron multiplication CCD
Figure: Wikimedia Commons The electron multiplication CCD
EMCCD output
The ixon EMCCD 0.5 CCD 1024 1024 pixels (normally 2 2 binning) 13 µm pixel area
Measured emissions Linjenätskarta Tunnelbana T10 Hjulsta T11 Akalla T14 Mörby centrum Ropsten T13 Tensta Husby Danderyds sjukhus Rinkeby Kista Rissne Hallonbergen T17 viss tid endast Duvbo Skarpnäck Odenplan, Näckrosen se tidtabell Sundbybergs centrum Vreten Solna centrum Huvudsta Västra skogen Bergshamra Universitetet Tekniska högskolan Stadion Karlaplan Gärdet Alvik Åkeshov Hässelby strand T18 T17 T19 Hässelby gård Johannelund Vällingby Råcksta Blackeberg Islandstorget Ängbyplan Åkeshov Brommaplan Abrahamsberg Axelsberg Mälarhöjden Stora mossen Alvik Örnsberg Aspudden Kristineberg Thorildsplan Liljeholmen Stadshagen Bredäng Midsommarkransen Sätra Fridhemsplan S:t Eriksplan Rådhuset Hornstull Zinkensdamm Odenplan Rådmansgatan Hötorget Mariatorget Östermalmstorg T-Centralen T11 Kungsträdgården T10 Gamla stan Slussen Medborgarplatsen Skanstull Gullmarsplan Skärmarbrink Skärholmen Telefonplan Vårberg Vårby gård Masmo Hägerstensåsen Fittja Alby Västertorp Hallunda Globen Hammarbyhöjden Enskede gård Blåsut Sockenplan Sandsborg Björkhagen Svedmyra Skogskyrkogården Stureby Tallkrogen Kärrtorp Bandhagen Gubbängen Högdalen Hökarängen Bagarmossen Rågsved Farsta T13 Norsborg T14 Fruängen T19 Hagsätra T18 Farsta strand Skarpnäck T17 Giltighetstid Förklaringar
Filters 3-inch 1 557.7 nm 2 427.8 nm 3 630.0 nm 4 Green background, 540nm 5 Blue background, 438nm 6 Red background, 620nm 7 Blocked 8 Empty (White light)
Optics Re-imaging lens Front lens Fisheye, 24 mm f/4 f/0.95
Outline 1 Imager details 2 Experience 3 Questions
Measurement site
Cameras colocated
Image sequence 1-minute sequence SEQ-0s GGGGGG SEQ-10s BBBB SEQ-20s GGGGGG SEQ-30s BBBB SEQ-40s GGGGG(G W) SEQ-50s RG bg B bg R bg
Presentation of data 16-bit images not suitable for web presentation...
Videos Bright aurora, Feb 28 17-18 UT, 5577, problems Weaker but still bright, Feb 28 22-24 UT, 5577 Weaker but still bright, Feb 28 22-24 UT, white Full moon, Feb 15 23,white
Summary of experiences Filter wheel RS232 communication a problem High EMCCD gain settings impossible at full moon Sometimes imaging works but images contain no data shutter? Presentation of the 16-bit data needs some development
Outline 1 Imager details 2 Experience 3 Questions
Camera operation modes Operate an emccd as a normal CCD? Switch between overview and campaign modes? Video rate possible Synchronise filter sequences Intercalibration
Projection N-S directions? Map to user-selected altitude? Scaling and calibration 16 to 8 bit scaling Gray and colour scales Background reduction Presentation of data
Data archiving No problem at normal operation with today s storage... But the cameras should be used at high frame rates in campaign mode to take full advantage of the EMCCDs More questions?
Data archiving No problem at normal operation with today s storage... But the cameras should be used at high frame rates in campaign mode to take full advantage of the EMCCDs More questions?
Data archiving No problem at normal operation with today s storage... But the cameras should be used at high frame rates in campaign mode to take full advantage of the EMCCDs More questions?