(meteorobs) Correction re: my Perseids report

[Nikola Bilišskov]

Bruce McCurdy wrote:
> Further to my Perseids report of August 13, I have conferred with my 
> observing buddy Alister Ling as recorded below. In retrospect I am 
> more satisfied with his estimate of limiting magnitude than my own. 
> Accordingly I wish to alter my limiting magnitude estimate, and submit 
> the revised report at bottom.
Well, in visual meteor astronomy, your (YOUR) eye is meteor detector. It 
is an instrument which works better or worse. Just like any other 
instrument, your eye has its own technical characteristics 
(perceptibility, view angle, dioptry,...), but some of eye 
characteristics are not constant in time. Eye is subject of 
unpredictable changes during the observation, due to the tire, 
physiological (is the observer well trained? Is (s)he tired? Is (s)he 
well dressed? etc.) and psychological (is the observer alone? Are the 
observers concentrated to sky or they constantly talk? etc.) state of 
observer. Another part of the story is about eye.. There are no two 
persons with the same eyes. Some of us can see thousands of stars, while 
some of us in the same sky conditions can see just a few.
So, all the meteor data you report must be yours. One cannot use meteors 
seen by another person in reduction of his/her observation data. So, you 
estimated one limiting magnitude, and your friend another. If you are 
not satisfied with your limiting magnitude estimation, you can estimated 
it more times during the observation, using several triangles. If you 
are not sure in your Lm estimation after the observation, report 
estimated Lm, or, in the worst case, cancel your observation, but don't 
use another observer's data!
Observer's perceptibility can be estimated from number of sporadics seen 
during 1h. It is also subject to rapid changes due to observer's state.
Best wishes and, off course, don't get discouraged.
Nikola