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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