(meteorobs) 2008 Orionids

[stange]

Ed and others,

Not all of us have the dark skies of high altitude or desert dark sky 
locations which enable enough stars to be captured with a meteor to be used 
for triangulation. For those of us with poor star capture, even with 
co-adding 10 frames with Sentinel, camera alignment is the only (practicle) 
solution. (Azimuth error of my station is at present 1.5 degrees maximum and 
has not been readjusted in about 2 years). 1 degree was the original error.

The capture of weak meteors with all sky cameras can be enhanced using a 
dual monitoring system such as is illustrated in my system diagram. It is 
the best way to go with regard to cost. The faint, and extremely fast, & 
short, meteor captures will more than impress anyone that tries a test 
augmentation of their current low light camera. The eye would not be able to 
detect many of these brief meteors, let alone their positions in the sky. It 
is even hard to keep up with them on playback because they are so fast and 
short.

I have absolutely no idea on just how good star capture would be using this 
system in a dark sky enviornment or to what degree faint meteor captures 
would be improved.

The capture settings on the parallel second monitoring system are so 
sensitive that it cannot even begin capturing meteors until 2 hours after 
Sentinel is running at ~ 6 PM.because of light washout.

For gen. info I add my Sentinel settings & the Parallel system settings. 
Diagram on my site.

....(Sentinel).......................................................(Handyavi)
Brightness = 160...........................................Brightness = 6400
Contrast = 139..............................................Contrast = 6000
Delay = 8......................................................Sensitivity = 
88.0
Trig. Thresh. = 8............................................Preframes = 7
UnTrig. Thresh = 2........................................Postframes = 11
Default Mask Value = 27...............................

I hope this comes out in verticle columns in this post.  -YCSentinel (with 
City skies)



----- Original Message ----- 
From: "Chris Peterson" <clp at alumni.caltech.edu>
To: "Global Meteor Observing Forum" <meteorobs at meteorobs.org>
Sent: 2008/10/24 17:01
Subject: Re: (meteorobs) 2008 Orionids


> Hi Ed-
>
> Most internally integrating video cameras are on the pricey side. I find 
> the
> best meteor sensitivity at full video rates. With a Watec 120N, dropping
> below 30fps brings out the stars better, but I miss dim meteors. So the 
> only
> reason to use a camera like this for meteor work is to collect an
> astrometric reference along with a meteor detection. But you can actually 
> do
> that pretty well by just collecting a few seconds of ordinary video and
> integrating them externally. Not as clean as internal integration, but
> you'll get 50 stars or more, which is plenty for astrometric calibration.
>
> In general, I don't think you can do better than a PC164C if you're okay
> with a 1/3" sensor, otherwise a Watec 902HS. Both are pretty inexpensive.
>
> BTW, I'd ignore the lux specs. They are pretty meaningless. The old PC23C 
> is
> only about a magnitude less sensitive to meteors than the PC164C, even
> though its lux rating is something like 100 times lower. I've seen 0.1 lux
> cameras that are more sensitive than 0.001 lux cameras.
>
> Chris
>
> *****************************************
> Chris L Peterson
> Cloudbait Observatory
> http://www.cloudbait.com
>
>
> ----- Original Message ----- 
> From: "Ed Majden" <epmajden at shaw.ca>
> To: "Global Meteor Observing Forum" <meteorobs at meteorobs.org>
> Sent: Friday, October 24, 2008 9:36 AM
> Subject: Re: (meteorobs) 2008 Orionids
>
>
>> Depending on the specs you look at these cameras have the same low
>> lux sensitivity 0.0003 at f1.2 - 1/60 sec.  What we need is a camera
>> where you can control exposure length, i.e. 1/30 sec or better 1/15
>> sec exposure.  Such a system may not be more sensitive recording
>> moving objects (meteors) but they should be capable of recording more
>> background stars for reference points for measurement.  The film
>> based MORP Cameras used chopping shutters with a chopping rate of 4X
>> per second.  A bit on the low side for velocities but Ian Halliday
>> used these rates successfully for his Fireball Network.    Anyone
>> know where one can find a video camera with low lux capability with
>> exposure length control that will not break the bank?
>> Ed Majden
>
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