How sensitive are optical timers to camera flashes?

General timing system discussions.
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Teeeman
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How sensitive are optical timers to camera flashes?

Post by Teeeman »

Does anybody have reasonbly firm evidence that corroborates flash photography upsetting an optical timer?


We saw some unbelievably "quick" times this year that had to be re-run at District.


Any way to combat this if it is in fact a problem?

(other than telling folks for the literally 5th time to stop, finally our MC pointed to a gent up on a balcony at the local mall and said "you sir!"... THEN the guy stopped finally)


-Terry
"I dunno..." - Uncle Eddie, Christmas Vacation
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gpraceman
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Re: How sensitive are optical timers to camera flashes?

Post by gpraceman »

Teeeman wrote:Does anybody have reasonbly firm evidence that corroborates flash photography upsetting an optical timer?
You'd have to ask the particular manufacturer. It all depends on the sensors they are using.

Having worked with many different timer brands, there are other possbile explanations for abnormally short times. Are you pretty confident that all of the issues related to this guy taking photos?
Teeeman wrote:Any way to combat this if it is in fact a problem?
There are some general anti-glare things that can be done to reduce light issues, which have been discussed many times on this board.
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Pinewood Daddy
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Re: How sensitive are optical timers to camera flashes?

Post by Pinewood Daddy »

One year we had our race at a different location with low ceilings and bright lights. Lane 1 suffered from random really fast times. We finally had to ignore all times from Lane 1. After reading the instructions (and talking to the mfg.) for the FastTrack timer I found the sensor holes in our track were too big. I think they are supposed to be 5/16" diameter and they were about 1/2", this allowed too much stray light to enter causing "noise" to interfere with proper operation. After the race I made bushings to reduce the size of the holes and colored the bores with black marker to further reduce the possibility of reflected light getting to the sensors.
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MaxV
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Re: How sensitive are optical timers to camera flashes?

Post by MaxV »

We had problems with late triggering on a Fast Track timer due to ambient light. We solved it with inserts and a flat black stripe across the finish line.

Here is an article that discusses this issue, with some photos showing the solution:
http://www.maximum-velocity.com/pinewoo ... imes-v7i2/
Teeeman
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Re: How sensitive are optical timers to camera flashes?

Post by Teeeman »

Thanks all!

Turns out my wife video'd the run...


after several folks doing independent reviews of it, we are on consensus that there was a timing error...

but the error was probably not at the finish line.


That said, camera flashes probably had NOTHING to do with it.

(none of us can spot a camera flash in the video as well)


-Terry
"I dunno..." - Uncle Eddie, Christmas Vacation
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