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Re[2]: (meteorobs) Leonids: max ZHR in 1966



     - Marco Langbroek posted on 10/23:
       
     "How many meteors you catch <SNIP> is highly influenced by your 
     equipment <SNIP> -a good heating device and flat film surface can 
     make a large difference. <SNIP> So much for the theory of rates 
     from photographs. And then, I don't even mention that most likely 
     only the best of the pictures were published -the ones that 
     catched that statistic flurry that happens once in a while."
     
     I am not the professional observer that many of you are, but I 
     did witness the '66 Leonids from a dark site in central 
     California in the US.  The conditions were not perfect; as is 
     often the case on the west coast at that time of year, there was 
     substantial cumulus overcast.  We watched the peak of the storm 
     thru a hole perhaps 35-40 degrees wide directly overhead.  There 
     were about 10 members of the local amateur astronomy group 
     present, and we attempted to keep counts and plot but as the 
     rates increased it became impossible...  we just watched the 
     show.
     
     I can comment that back in those days most of the techniques of 
     hypering film and heating cameras to increase sensitivity had not 
     been discovered or widely known.  I doubt seriously that 
     photographic records were done with other than plain high speed 
     film in ambient conditions... but could be corrected if anyone 
     knows better.  The number recorded would of course be a function 
     of film speed, focal length and focal ratio, etc.
     
     As for catching a statistical flurry... it belittles the nature 
     of the storm to talk of flurries.  During the 15 minute peak the 
     meteors were coming in a constant rain, with a fairly uniform 
     distribution of magnitudes.  Any 30 second reasonably wide angle 
     exposure would have caught a sample that well represented the 
     mean.
     
     Just an old timer's recollections.
     
     kevin_wells@cohr.com