(meteorobs) OT-Possible single stationdeterminationofmeteordistance.

[stange]

You are likely right.

I had earlier estimated 1.44 seconds for a 30 mile meteor if I remember 
right late last night.

I had considered(1us), phase locking both cameras from one cameras time 
bases but without a schematic (or even with one) it is more work than I 
intend to do. If it is not simple now-a-days.... I look for another way or 
scrap the project. I stay away from external synch cameras and monitors 
because in used condition they are mostly boat anchours.

Got two fireballs last night. One is a reasonable detonation, the other is a 
wet firecracker. Am processing images to go into the IR image library now.

BTW -Found more data on J.D.'s camera. The CB803S is a 0.3 lux camera. If 
his is similar without the shutter speed selections(S?).... it won't bode 
well for any meteor capture....

Thanks Chris.
-Larry

----- Original Message ----- 
From: "Chris Peterson" <clp at alumni.caltech.edu>
To: "Global Meteor Observing Forum" <meteorobs at meteorobs.org>
Sent: 2008/12/17 16:55
Subject: Re: (meteorobs) OT-Possible single 
stationdeterminationofmeteordistance.


> There are two ways you can mix video signals. You can use a pair of 
> cameras
> that share a common timebase. Some cameras allow an external sync from
> another camera, but it isn't a common feature. It isn't too hard to
> implement yourself, but it does require some fine assembly and the running
> of signals between the two cameras. The other approach is an external
> circuit that delays and rebuilds one signal to be in sync with another. 
> This
> isn't very simple.
>
> I don't think it matters, however, because I don't think your approach is
> practical. The method depends on measuring parallax, and at the distances
> involved the parallax is just too small. The position shift between your 
> 10
> mile reference and any meteor will not exceed about 20 arcsec, which is
> going to be very difficult to detect. You will need very high quality
> lenses, you probably can't use protective domes, and your astrometric
> calibration will need to be almost impossibly good. The angular separation
> between the images from the two cameras for a meteor 70 miles away will be
> about 3 arcseconds. That is on the order of 1% of your pixel spacing. That
> is simply not measurable with this setup. Even good lenses are not
> distortion free at that scale.
>
> Chris
>
> *****************************************
> Chris L Peterson
> Cloudbait Observatory
> http://www.cloudbait.com
>
>
> ----- Original Message ----- 
> From: "stange" <stange34 at sbcglobal.net>
> To: "Global Meteor Observing Forum" <meteorobs at meteorobs.org>
> Sent: Wednesday, December 17, 2008 4:11 PM
> Subject: Re: (meteorobs) OT-Possible single station
> determinationofmeteordistance.
>
>
>>I was reviewing M&M + light speed for "ideas" of how to EASILY make a
>> ranging device that was cheap and simple. I ruled out split image and
>> mirrors as being totally impractical and could not find any sound idea
>> using
>> that material for what I wanted.
>>
>> At present the only concept that I think is workable & easier, is
>> investigation into reverse autoranging using two cameras. The idea seems
>> sound, but whether it can be made practicle and can stand alone in
>> operation
>> is the difficulty.
>>
>> It can be done with a memo-scopes or a dual trace trigger and other ways
>> but
>> stand alone multiple triggering with hard drive storage is key functions
>> needed all night long to be realistic.
>>
>> My tests this afternoon on reversing the splitter determined two 
>> identicle
>> cameras nearly synched in a lock-on but repeated out of phases would 
>> cause
>> thousands of false triggers with a capture program. So that is the
>> problem.
>> "HOW" to get automatic overlays or two image captures AND storage of
>> stable
>> events without 2 computers running independantly with split capture and 
>> at
>> no cost to the user like having to double up on capture cards & having a
>> two
>> processor computer. A hardware Engineer is needed here or someone to
>> follow
>> up on anything with what little merit I have given.
>>
>> Basic dwg. illustrating the simple principles without ccd diagonal 
>> measure
>> correction.....
>> http://www.geocities.com/stange34@sbcglobal.net/Distance
>>
>> YCSentinel
>
> _______________________________________________
> Mailing list meteorobs: meteorobs at meteorobs.org
> To UNSUBSCRIBE, email: owner-meteorobs at meteorobs.org
> http://lists.meteorobs.org/mailman/listinfo/meteorobs