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Re: (meteorobs) Observer Perception


Best way to do is using the sporadic background. correct sporadic rates for
Lm first:

HR= Nspo * 3.4^6.5-lm

...And of course for effective observing time (transform to 1 hour periods
by 1/Teff, with Teff in hours)

Take a sample of several nights per observer. Calculate sporadic HR's in
approximately 1 hour intervals  (see above) and then average into an
average HR. Preferably, do this with summer data from a few hours around
local midnight (say 22-02h Local time).

The average observer is defined as one that sees 10 sporadics/hour with Lm
at +6.5 in august (around November, this is approx. 12/hour). This is the
standard observer that has Cp 1.0

Now calculate your Cp with regard to this 'standard observer' by dividing
your average sporadic HR as calculated according to the above by 10:

Cp=<HRspo>/10

If you are close to the 'standard observer' your Cp will be near 0.8-1.2
(0.8 means that you see 0.8 of the 'standard observers' HR etc.). Don't
bother if you are above or below this. Such are usually (not alway) just
due to biologic differences (eye quality, age etc.). Sometimes, apparently
very high Cp's are due to observers underestimating their Lm seriously.

Use the CP calculated to upgrade or downgrade your stream rates by a factor
1/Cp in order to normalize rates to those seen by the 'standard observer'

This is the method we use in the Dutch Meteor Society since the last 15
years and it works fine usually. This is also the method employed by peter
Jenniskens in his 1994 Astron. Astrophysics paper on annual meteor activity.

-Marco Langbroek (DMS)







At 22:09 1998-07-12 +1000, you wrote:
>A little while back there was a short thread on Observer Perception.  What
I want to know, is there any reliable (or near
>reliable) formula for calculating observers perception ?  It would be
handy to be able to calc it for different observers in a
>group, say if your monitoring a stream and you have 4-5 observers, it
makes the results easier to work with and more valid.
>
>Thanks in advance, Adam.
>
>
References: