|
Leonids
'01 recording with a Watec-902H and wide angle auto-iris lens
|
||||
|
yKChia
Nov 26 01 Rev 1.2
|
||||
|
|
||||
|
I
first tried out a watec 902H and a 3.8 mm f/0.8 auto-iris lens 89 x
69 degree FOV lens on a tripod in desert camp of Jordan (1999). The
result was pretty interesting - at UT 02 hrs -just two hours before peak
then I recorded a total of 35+ Leonids in slightly half an hour. Encouraged
by the low light detectability of this simple set-up I repeated this year
November 19 Leonids in Bohyunsan Optical Astronomical Observatory,Korea
with a similar ccd and lens. This time the video was recorded using a
Digital 8 Sony video walkman GV-D800E running on 1-hour duration in LP
mode. Upon my return from Korea I spent some time watching and counting
the meteors in a high resolution b/w
montior. In total I had recorded a minimum of SIX HUNDRED & THIRTEEN
(613) meteors in just 1.88 hrs effective hours. The 'one-minute'
bin was depicted in the graph attached here. There are spikes where high
counts are seen momentarily. [The red line indicate the cumulative counts.]
Despite missing data in three periods the overall envelope indicate a
broad plateau at least for the BRIGHT meteors brighter than mag 1.0. To
achieve a lower detection magnitude, another longer focal length lens
could be used. My brand new 25mm f/0.90 Avenir TV lens and watec-902H
had a LM Of ~+8.0 and FOV of 13 x 8 degree. I used this pair for train
spotter. Too bad the Li-ion battery of this recorder failed which prevented
me from recording extended hours. In this short duration tape a torrents
of faint meteors at burst rate 1 per second was seen accompanying the
brighter one. |
||||
| ( under construction) First trial of Meteor Train using video - Avenir 25mm & watec 902H | ||||
| ( under construction) How the Canon T-70 Array stack up against watec.[ hint : no fight] | ||||
| HOME | ||||