Optical 16 Aug 2007

From: Greg Roberts (grr@telkomsa.net)
Date: Fri Aug 17 2007 - 11:26:25 EDT

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    Observations 16 Aug 2007:
    Cosatrak 1 (Computerised satellite Tracking System).
    MINTRON low light level CCD surveillance camera (0.005 lux typical
    in non integration mode) and 0.00005 lux in STARLIGHT mode with 128
    frame integration.
    Used with 6 inch f/2.7 Celestron reflector. This is normally f/5 but
    using a homemade focal reducer it is now f/2.7 and the field of view
    49 x 39 arc minutes. I was using very short integrations as mount was
    unable to track.
    Site 0433 : Longitude 18.51294 deg East, Latitude  33.94058 deg S,
    Elevation 10 metres - situated in Pinelands (Cape Town), South Africa
    For Classified .tle:
    28385 04 034B   0433 F 20070816175226300 56 15 1324455-473416 39  +065 05
    28385 04 034B   0433 F 20070816175230900 56 15 1326516-472600 39  +070 05
    28385 04 034B   0433 F 20070816175234300 56 15 1328254-471943 39  +080 05
    (1) After a great deal of cloudy weather and rain the past few weeks it
        finally cleared enough to warrent setting up equipment. The main
        purpose was to evaluate a home made focal reducer made from a 32 mm
        diamater objective lens, focal length 89mm, obtained from an "opera
        glass" bimocular. I did not expect too much as f/5 is already pretty
        fast for a reflector but the resultant images are not at all bad and
        I will make another focal reducer and see if I can get the 6 inch
        down to f/2. I wrote a short program to design focal reducers so its
        easy to evaluate lens distances etc.
    (2) In the final stages of setting up the CoSaTrak computer refused to
        communicate with the interface to the stepper motors so I was unable
        to track using the CoSaTrak system so I occupied myself for a while
        just sight seeing and examining image quality. Whilst looking at the
        globular cluster Omega Centauri a brightish flashing satellite
        passed through field of view which proved to be the "classified"
        satellite above.
    (3) CoSatrak now back in action - CMOS PC battery dead and turned
         out the default values of the parallel port address is NOT the same
        as that used by CoSaTrak hence the "freeze-up" - really had me
    (4) hopefully the clear weather has now come to stay
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