Milstar 5 video obs

From: Brooke Clarke (brooke@pacific.net)
Date: Sat Mar 01 2003 - 10:34:28 EST

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    Hi Rainer:
    
    I have done some analysis of the Mintron 12V1C-EX (StellaCam EX) in terms of its light sensivity.
    <http://www.pacificsites.com/~brooke/Mag.shtml>
    But the thing that bothered me about using the integration mode on a fast moving sat was that if the sat changed pixels then the
    integration would make the image dimmer.  Or does it just reduce the contrast?
    
    Have you tried different integration times?
    
    A 75 mm f1.3 lens is 75/1.3 = 57.7 mm objective diameter and according to the table on my web page should see MAG 9.5 with no integration.
    
    It's interesting that the 82mm/f1.6 = 51.3 mm OD is not as good a lens.
    
    How do you point the camera?
    
    What is a 1004a?
    
    Thanks,
    
    Brooke Clarke, N6GCE
    123.164041W 39.190192N
    
    
    > Subject: Re: Milstar 5 video obs
    > Date: Sat, 1 Mar 2003 11:23:12 +0100
    > From: R.Kracht@t-online.de (Rainer Kracht)
    > To: SeeSat-L@satobs.org
    >
    > On 28 Feb 2003, at 15:15, Greg Roberts wrote:
    >
    > >
    > > >Date: Thu, 27 Feb 2003 00:33:44 +0100
    > > >From: R.Kracht@t-online.de (Rainer Kracht)
    > > >To: SeeSat-L@satobs.org
    > > >Subject: Milstar 5
    > >
    > > >observations with my new video camera (Mintron 12V1C-EX)
    > > >f=75 mm, f/1.3
    > >
    > > Hi Rainer,
    > >
    > > Very pleased to see that someone else has now started to make use
    > > of a sensitive video camera for satellite tracking - the Mintron
    > > is a nice unit but a little too expensive for me unfortunately.
    > >
    > > Did you use the camera in the integrating mode in order to reach
    > > magnitude 10.7? - I would not have thought it capable of going
    > > that faint in video mode as there is no way I could reach that
    > > faint. Im using a 1004x camera f=82mm, f/1.6 and this can reach
    > > about +9.4 in good conditions with my bright city lit sky.
    > >
    > > Willie Koorts tried his new 1004x ccd camera on a 9 inch reflector
    > > and was able to reach about magnitude +12 in video mode - ie about
    > > 1/50th second exposure.
    > >
    > > Hope to see more people making using of video cameras as this is
    > > the way to go !
    > >
    > > Good luck
    > > Greg
    > >
    > My city lit sky is also quite bright, I think the naked eye limiting
    > magnitude was about mag 3 for the Milstar videos. The exposure time
    > was set to 20 ms and the integration to 64x giving a total exposure
    > time of 1.28 seconds per frame (0.78125  fps). The camera was fixed
    > (no guiding).
    > The pixel size of the Mintron (Sony) CCD is 0.008 x 0.008 mmm.
    > With the 75 mm lens this corresponds to 22 arcseconds (1.47
    > seconds of time at the celestial equator).
    > The field of view is a comfortable 4.9 x 3.7 degrees.
    > This is a small, easy to use and powerful device.
    >
    >  Rainer
    >
    > Rainer Kracht
    > Elmshorn, Germany
    > Station 5005
    > 53.7695N 9.6626E  9m Potsdam Datum
    > 53.7679N 9.6614E 47m WGS84
    > R.Kracht@t-online.de
    
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