Optical 15 April 2009

From: Greg Roberts (grr@telkomsa.net)
Date: Thu Apr 16 2009 - 14:24:00 UTC

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    Observations 15 April 2009
    ------------------------------------
    
    Cosatrak 1 (Computerised satellite Tracking System).
    Camera mount now carries two systems that can be operated
    together as two totally different sytems and computers used.
    Generally the DSI Pro II camera will be used for high altitude
    slow moving objects. Tests seem to indicate that its sensitivity
    is comparable to the MINTRON ( possibly better) but as its not
    possible (?) to time stamp to better than 1 second accuracy the
    time resolution is not good enough for LEO objects.
    
    (1) 145mm focal length f/2.5 lens fitted to 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.
    Image integrated for 2.56 seconds but exposure depends on sky background
    brightness. Field of view 2.5 x 1.9 degrees and showing about mag +12
    stars in "real time". Used as a finder for the 6 inch reflector.
    Individual frames are video time stamped with GPS derived signal.
    
    (2)Meade DSI Pro II Monochrome CCD camera without filters.
    using integration times of 5 sec min to 25 seconds maximum
    depending on brightness of sky in particular area.No image
    processing done, but some done automatically in the auto reduction
    software
    .
    Used with 4 inch SKYWATCHER refractor- model 1025 - fitted with home
    made focal reducur to give an f/2.56 system. Image scale is 6.56 arc
    sec/pixel and field of view 84.8 x 63.2 arc minutes. This telescope
    will replace the 6 inch reflector used previously as image quality is
    better, has a larger field of view, less surface area so less prone to
    wind shake, and in addition is at least as sensitive, if not superior
    to the 6 inch reflector. Shows 15th magnitude stars in real time with
    reasonably good conditions.
    
    Exposure time to nearest second inserted into image FITS header
    from PC clock which is automatically checked every minute against
    GPS signal.
    
    Site 0433 : Longitude 18.51294 deg East, Latitude -33.94058 deg,
    Elevation 10 metres-situated in Pinelands (Cape Town),South Africa
    
    For CLASSFD.TLE:
    --------------------------
    96010 96 510A   0433 P 20090415193019500 16 35 1142163+064801 19  +118 69
    96010 96 510A   0433 P 20090415193035500 16 15 1142213+062756 28  +134 89
    96010 96 510A   0433 P 20090415193052500 16 15 1142345+062744 28  +130 02
    96010 96 510A   0433 P 20090415193108500 16 15 1142477+062733 28  +133 35
    96010 96 510A   0433 P 20090415193124500 16 35 1143008+064554 78  +135 96
    96010 96 510A   0433 P 20090415193141500 16 15 1143130+062703 28  +130 05
    96010 96 510A   0433 P 20090415193157500 16 15 1143263+062653 28  +135 03
    96010 96 510A   0433 P 20090415193213500 16 15 1143388+062638 38  +134 04
    96010 96 510A   0433 P 20090415193230500 16 15 1143519+062627 48  +136 06
    96010 96 510A   0433 P 20090415193246500 16 15 1144047+062613 38  +136 03
    33490 09 001A   0433 P 20090415173058000       1034571+053909     +080 05
    33490 09 001A   0433 P 20090415173252000       1036505+053709     +080 05
    33490 09 001A   0433 P 20090415184309000       1147081+043837     +080 05
    33490 09 001A   0433 P 20090415184658000       1150570+043539     +080 05
    33490 09 001A   0433 P 20090415192429000 16 15 1228265+040546 18  +081 00
    33490 09 001A   0433 P 20090415192441000 16 15 1228379+040537 97  +081 00
    33490 09 001A   0433 P 20090415192452000 16 15 1228491+040528 28  +082 00
    33490 09 001A   0433 P 20090415192503000 16 15 1229005+040520 28  +081 01
    33490 09 001A   0433 P 20090415192515000 16 15 1229119+040510 18  +081 00
    33490 09 001A   0433 P 20090415192526000 16 15 1229231+040502 28  +082 01
    33490 09 001A   0433 P 20090415192537000 16 15 1229343+040453 18  +082 00
    33490 09 001A   0433 P 20090415192548000 16 15 1229455+040444 18  +082 00
    33490 09 001A   0433 P 20090415192600000 16 15 1229570+040436 97  +082 00
    33490 09 001A   0433 P 20090415192611000 16 15 1230081+040427 18  +082 00
    33490 09 001A   0433 P 20090415192622000 16 15 1230195+040418 77  +082 00
    33490 09 001A   0433 P 20090415192634000 16 15 1230308+040409 97  +082 10
    33490 09 001A   0433 P 20090415192645000 16 15 1230421+040401 87  +081 01
    33490 09 001A   0433 P 20090415192656000 16 15 1230535+040352 18  +082 00
    33490 09 001A   0433 P 20090415192708000 16 15 1231048+040344 18  +082 01
    28500 04 050A   0433 P 20090415201032000 16 15 1128561+115438 38  +123 03
    28500 04 050A   0433 P 20090415201103000 16 15 1130068+115754 58  +112 02
    28500 04 050A   0433 P 20090415201118000 16 15 1130412+115926 28  +109 01
    28500 04 050A   0433 P 20090415201133000 16 15 1131154+120058 28  +108 01
    28500 04 050A   0433 P 20090415201148000 16 15 1131495+120230 28  +107 01
    28500 04 050A   0433 P 20090415201204000 16 15 1132231+120358 38  +106 01
    28500 04 050A   0433 P 20090415201219000 16 15 1132573+120530 38  +107 14
    28500 04 050A   0433 P 20090415201340500 16 15 1135539+121312 58  +114 02
    28500 04 050A   0433 P 20090415201413500 16 25 1137095+121656 59  +069 60
    28500 04 050A   0433 P 20090415201429500 16 15 1137436+121805 78  +130 04
    28500 04 050A   0433 P 20090415201445500 16 15 1138195+121943 59  +125 16
    
    Stray seen:
    ------------
    16676 86 027F   0433 E 20090415201849500 16 15 1145568+123700 38  +131 03
    16676 86 027F   0433 E 20090415201903500 16 15 1146105+123619 48  +133 04
    16676 86 027F   0433 E 20090415201917500 16 15 1146246+123535 78  +109 10
    16676 86 027F   0433 E 20090415201932500 16 15 1146377+123438 48  +130 03
    16676 86 027F   0433 E 20090415201946500 16 25 1146841+123321 38  +121 19
    16676 86 027F   0433 E 20090415202000500 16 15 1147044+123253 28  +143 04
    16676 86 027F   0433 E 20090415202014500 16 15 1147181+123156 28  +136 03
    16676 86 027F   0433 E 20090415202029500 16 15 1147319+123124 48  +129 03
    16676 86 027F   0433 E 20090415202043500 16 15 1147451+123016 58  +127 03
    16676 86 027F   0433 E 20090415202057500 16 15 1147583+122928 38  +136 03
    16676 86 027F   0433 E 20090415202111500 16 15 1148117+122828 68  +128 03
    16676 86 027F   0433 E 20090415202126500 16 15 1148255+122739 48  +134 04
    16676 86 027F   0433 E 20090415202140500 16 25 1148644+122680 19  +135 15
    
    
    Notes:
    --------
    
    (1) Testing out a new telescope and the auto reduction program APEX-II.
        After the first two hours trying out various optical configurations
        I came to the conclusion that I had wasted my money and had a "dud"-
        the problem was how to explain that to my wife ! Images taken with
        a commercial focal reducer in the scope were very "soft" - ie could
        not focus to a "star point". I even tried the telescope at prime
        focus-ie using it as an f/5 refractor but image quality still very
        poor so I put it down to "you get what you paid for" - after all a
        4 inch refractor for $400 ( made in China) is dirt cheap when a high
        class 4 inch refractor costs at least 10 or more times this price.
    
    (2) I then tried my cheap home made focal reducer- the objective lens
        from a 2x opera glass - and got perfectly acceptable images-big sigh
        of relief! I spent the rest of the evening playing around with the
        system taking "pretty pictures" and added a few satellites for fun.
    
    (3) All the measures above - except for those of 33490 USA202 with no
        code, were done with the new system and processed automatically in
        APEX-II with no problems whatsoever - the more I use this program
        the more impressed I become with its capabilities. If everything
        set up correctly it measures an image in less than 20 seconds.
    
    (4) The stray satellite seen was a faint smug right in the corner of
        images taken of the particular area and I did not think APEX-II
        could process it but it had no trouble.
    
    (5) Specially for Mike :-))))
        --- this is probably the last time I will report all the images
        processed - in future I will report a maximum of 2 or 3 images per
        satellite instead of a measure from each image taken.
    
    
    Now to wait for clear weather!
    
    Cheers
    Greg
    
    
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    This archive was generated by hypermail 2b29 : Thu Apr 16 2009 - 14:26:54 UTC