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Re: (meteorobs) Video Observing

There are several points I want to respond to in this thread, but
won't have time to do so fully until the weekend.

In the meantime here are a few brief points.

Our video cameras use second-generation MCPs with gains around 30000x
and a 25mm screen.  The reason they only cost around $140 is probably
because they have poor cosmetic quality, poor flat field, and 25%
distortion.  They come with a built-in transformer and can be run off
batteries.  By buying a few we were able to select the best
intensifiers.  Most seem to have a peak sensitivity in the visual.
One we found had a rising quantum efficiency towards the infra-red, but
cosmetically it was very good.  The intensifiers originate from the UK
(and Germany?).  We've only tried a hand-held Russian night 'scope,
you know the sort the East-German border guards used.  The phosphor
diameter is smaller AFAIR.  The surpliers are Anchor Surplus Ltd.,
The Cattle Market Depot, Nottingham NG2 3GY, U.K.  Tele: +44-115 986 4902
Fax: +44-115 986 4667.  The numbers in stock vary.  Sometimes they have
had several and other times none.

We use a relay lens (which appears to be causing vignetting in one of
the two cameras) to image the phosphor on to a Vidicon/Newvicon
camera.  These security cameras cost around $100. I'd rather have a
CCD if we could store the data digitally without an A-to-D converter.

Our biggest problem, and which has prevented me from testing some
software ideas for automatic reductions, is the lack of a video-to-PC
card.  The ones we bought didn't work and the firm went bust.  I
see that more are availble.  Anchor advertise PAL to AVI cards
($100 for 260-line, $140 for 520-line).

I think we still have scope for developments to the software both
in automatic location and analysis.  Hardware processing may be
needed to obtain the throughput.  Of course the speed of PCs is
continuing to increase, so tomorrow's software can be more
sophisticated and still have (near) real-time processing.

Have to go now.

Malcolm
References: