Obs 28/31 July 2005

From: Greg Roberts (grr@iafrica.com)
Date: Mon Aug 01 2005 - 09:56:36 EDT

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    Observations 28/31 July 2005:
    ----------------------------
    
    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.
    
    28th July: Used with 50mm focal length f/1.8 lens.Field of view
    6.9 x 5.4 degrees and can see stars down to mag 11.   64 frame
    integration used.
    
    31st July: Used with 11-70mm focal length f/1.3 telephoto lens set
    at approximately 50mm focal length.Can see stars down to at least
    10th magnitude but heavy cirrus prevented a more accurate
    determination. It SHOULD be better than the lens used on the 28th.
    64 frame integration used.
    
    Site 0433 : Longitude 18.51294 deg East, Latitude  33.94058 deg S,
    Elevation 10 metres - situated in Pinelands (Cape Town), South Africa
    
    "Strays" observed whilst watching RA 14h44m    Dec -34d 00'
    
    28th July (continued):
    -----------------------
    
    Solrad 7B
    01291 65 016D   0433 G 20050728173101800 56 15 1452420-350807 39  +070 05
    Navstar 47 rocket
    26362 00 025C   0433 G 20050728173651200 56 15 1444010-340407 39  +050 05
    Navstar 34 rocket
    22781 93 054C   0433 G 20050728174458900 56 15 1449340-323750 39  +065 05
    Thor Agena B rocket
    00426 62 049B   0433 G 20050728175545300 56 15 1440340-355556 39  +045 05
    GFO
    25157 98 007A   0433 G 20050728180933500 56 15 1430520-362115 39  +050 05
    Fengyun 1A
    19467 88 080A   0433 G 20050728181833700 56 15 1439450-352947 39  +040 05
    Molniya 1-32
    08601 76 006A   0433 G 20050728184039800 56 15 1447160-315610 39  +070 05
    Cosmos 2042
    20236 89 074E   0433 G 20050728185842500 56 15 1452270-324845 39  +075 05
    Cosmos 2384
    27055 01 058A   0433 G 20050728185940300 56 15 1455020-333721 39  +072 05
    SL-19 rocket
    23440 94 085B   0433 G 20050728191851100 56 15 1456250-311246 39  +060 05
    
    31st July:
    -----------
    
    Ariane 40 R/B
    25979 99 064C   0433 G 20050731171218700 56 15 1436350-351915 39  +030 05
    Atlas Centaur rocket
    03598 68 110B   0433 G 20050731172528600 56 15 1446310-362406 39  +030 05
    Cosmos 588
    06845 73 069A   0433 G 20050731172640300 56 15 1430410-364627 39  +050 05
    Scout X-4 rocket
    01739 64 093B   0433 G 20050731173411700 56 15 1446550-364447 39  +070 05
    
    
    Notes:
    --------
    (1) Main purpose of tracking sessions was to evaluate different lenses
        and techniques.
    
        It would appear that in the case of a stationary camera a typical
        LEO satellite faintest magnitude would be about 3 magnitudes
        brighter than the faintest star seen.This depends on sky conditions
        but this seems to fit my bright Cape Town sky.
    
    (2) The MINTRON camera was designed for commercial surveillance 
          use and apart from about 4-5 pages of general information the so called
        "manual" is useless. After surfing the internet I was not much the
        wiser as there were conflicting suggestions so I decided to
        determine my own "best" operating procedure, so, to add to the
        confusion out there, here are mine:
    
        Camera set on ELC ( electronic light control) at Max level.
    
        Camera set on AGC maximum. Apart from the SENSE ( ie number of
        frames to integrate) the remaining controls do not appear to have
        any effect.
    
        ALC (automatic light control) takes too long to recover if the
        background light level changes suddenly - ie moving from the zenith
        to the bright city lit horizon.
    
        If the camera is operated without AGC, or AGC set less than maximum,
        some stars will show "doughnuts" - ie a black "ring" around the star
        due to over saturation of the star image.
    
    (3) I also decided to read my DVD manual more thoroughly and discovered
        that one can control the input and output signal. My particular
        unit -PIONEER DVD-320-S  has preset values as well as the ability to
        store particular settings in three memories for each "in" or "out",so
        hopefully this will improve the image quality as I noticed that the
        image recorded directly to hard drive from the camera (though a
        PC capture card) was superior to the image outputted from the DVD
        recorder.More detailed tests had to be abandoned on the 31st July
        due to very thick cirrus (?) eventually whiping out all stars
        except for a few brighter than magnitude +2.
    
    
    Cheers
    Greg
    
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