Question for Jeff Foster and Dave Kommel
 

How can a flash of visible light, e.g. a camera flash, trigger an infrared sensor? Or do cameras emit infrared radiation?

And who is the genius taking flash pictures before BOTH cars leave the starting line?

Re: Question for Jeff Foster and Dave Kommel
 

Might it be the infrared focusing cameras use?

Re: Question for Jeff Foster and Dave Kommel
 

Sounds like the $50,000.00 electronics timimng system has a flaw ????

Re: Question for Jeff Foster and Dave Kommel
 

The newer generation of cameras, containing high powered flashes and infrared, will trigger a photocell if it is aimed on the line-of-sight of the photocell.

Although they are designed to be operated in ambient light, the larger the photocell, the more prone it is to be affected by a bright flash or infrared devices.

This appears to be a rare case in which a photographer aimed his camera and it happen to be in the line-of-sight of the photocell.

Re: Question for Jeff Foster and Dave Kommel
 

As you can see from another post I thought at least some timing systems used laser light rather than infrared. Is that true or just a misconception on my part?

Bill

Re: Question for Jeff Foster and Dave Kommel
 

According to my conversations with Jeff Foster, it can happen. As to Toby's question about the genius shooting before both cars had left, if you have a handicap over a second, it's the only way to get both cars in the photo.

That said, with the newest generation of cameras with very good low light performance, we use flash much less frequently than in the past, but Pomona creates unique problems. You have the Musco truck on the west side of the race track putting out a tremendous amout of light on the starting and no light other than the ambient on the east side, therefore the only way to properly expose the east side of the car once it gets dark (or close to it) is to use flash.

The answer is to not shoot directly on the starting, but rather back behind the line, so that you have the stationary car in the foreground and the slower car as he is 20-40' out. The safe distance away from dead perpendicular is open to debate. Graham would probably like it to be 100 yards, while I think 10' is probably sufficient.

Re: Question for Jeff Foster and Dave Kommel
 

No laser. I believe Compulink went from photocell to infrared on most of their timing systems. Still, infrared can also be affected if the camera flash is powerful enough and if is on the line-of-sight.

Re: Question for Jeff Foster and Dave Kommel
 

toby what happened to ask that ?

Re: Question for Jeff Foster and Dave Kommel
 

This could be cleared up if there was a demonstration of how it can happen? Surely intentionally aiming a camera to try and make it happen would result in it happening almost every time?

Re: Question for Jeff Foster and Dave Kommel
 

First off, I just want to say that flash pictures should NEVER be taken until both cars have left the starting line. What do you think is more important, having a fair race without the possibility of a rerun or getting both cars in the photo? If we took a poll I don't think it would even be close. If you have to have both cars in the photo, go stand on a ladder at the 330' marker or at half track, whatever it takes, just don't take any flash pictures until both cars have left the starting line.

Have you ever tried concentrating on the tree with a camera flash going off in your face? I have. Back when I used to run my bracket car I was racing in Boise at the Nightfire Nationals. I was leaving off the top bulb. When the top bulb was about come on a flash went off in my face. When I could see again the second bulb was on. Not fun. I assume nobody would do that nowadays, but I wouldn't even want a flash going off behind me either. Somebody told me the photographer in the Dan Mason incident was about 10' behind the line.

I did a little research on cameras and they use infrared to trigger external flashes for better lighting. Dave, does your camera have the capability to use external flashes? If so, it uses infrared to control them.

I don't buy that it's the flash from the camera that's causing the red lights. If the sun reflecting off of a finely polished chrome plated front wheel doesn't trigger a red light, then how is the flash from a camera doing it? I bet it's the infrared from the camera that's causing it. Visible light is a different wavelength than infrared and it shouldn't matter how powerful the flash is.

And how many times does it happen when nobody notices it? Let's say a driver is about to cut a .150 light, but the photographer takes a picture at just the the right time and he gets a .025 light? Or a close red light?

I'm with Bill. I'd like to see a demonstration of this happening with just the flash part of a camera. If this can happen with just a flash from a camera, something is wrong. I believe it's caused by the infrared signal sent out by these cameras to control external flashes.

And once again, flash pictures should NEVER be taken until both cars have left the starting line. I hope you will tell other photographers this because there should NEVER be a rerun because of a photographer.

Re: Question for Jeff Foster and Dave Kommel
 

[QUOTE] And once again, flash pictures should NEVER be taken until both cars have left the starting line. I hope you will tell other photographers this because there should NEVER be a rerun because of a photographer. [QUOTE]

I fully agree!!!! What is more important?

Re: Question for Jeff Foster and Dave Kommel
 

Toby, the flash intensity can be adjusted in much of the professional equipment used at the races.
Many electronic flash systems have a capacitor that can generate several hundred volts and the energy is measured by Watts-Second.
Again, if by coincidence the flash is on the line-of-sight, it can trigger the photocell or infrared.

Re: Question for Jeff Foster and Dave Kommel
 

Do you have a link or a demonstration to back this up? An infrared sensor should only respond to infrared light. It shouldn't matter how many volts or watt-seconds the light is. The wavelength of visible light is different than IR light.

I agree that a camera flash could trigger a photocell, but not an IR sensor.

Re: Question for Jeff Foster and Dave Kommel
 

The camera flash thing is bs. The car doesn't even light the bulbs when his rear ties rolled through. If the camera was a problem it wouldn't make both of the lights go out they would blink, but what would I know I'm just using common sense. The main problem is the compulink system works off of a DOS system my cell phone has more technology than a compulink computer. Come one NHRA I think it's time to upgrade your POS timing system. I was involved in two reruns last year one at a big money bracket race and one at the Dallas national both were using compulink. NHRA needs to stop making up excuses and fix that outdated equipment.


Will Carrell

Re: Question for Jeff Foster and Dave Kommel
 

I've been bitten by the camera flash thing a few times, once at Bakersfield points race in the final and I was chasing a slower car, the perp. was on my opponents side of the track and before the 60' clocks. That flash shot straight thru the tree into my face. Me and him had a few words afterwards !! Mike R was involved in the discussions as well.
NO RE-RUN !!!!!!!!!!!!

The other significant time was in the final at Atlanta Nat., I was driving pretty good but I got a red against me in the semi's and my tree was off, at that point ya gotta blow it off but the same thing happened in the final with a more slower car and I sucked again, even mentioned it in the winners story in ND. Wasn't until I got the ND that I noticed the shot of Scott H's Q car leaving with a shot from behind that i understood the problem that time. There was more than one flash that time !!

Sorry Dave, but Toby is right, there should not be any flash photography until both cars leave. Even with the slightest chance of the flash being seen by any driver, where does it say that a photographer should be able to control the outcome of a race !! NUFF SAID !!!

Re: Question for Jeff Foster and Dave Kommel
 

I think before anyone flies off the handle as to the root cause of the problem, I'd like to see it duplicated as Bill Koski suggests. If it was caused by a photographer's flash (No it wasn't me as I was shooting top end at the time), I had thought we fixed the problem of "shine-back" we used to have with the old spotlight and photocells where flash/sunlight/moonlight/whatever would cause a red light even though the car hadn't moved. Again, I thought going to the infrareds stopped that problem. My question is if it's back, should we be going back to black front wheels or shoe polishing them like we used to do?

Now if the problem is an infrared signal coming from the camera to light a flash, I didn't notice anyone on the starting line when I was there using remote triggering of flashes. That doesn't mean the camera wasn't still emitting an infrared signal anyway, but that's beyond my knowledge of cameras.

I've also had "red-light problem" happen to me and I never liked nor understood the answers given as to the cause. Other than wanting to see it duplicated, the only question I have is: Do we have to go back to black wheels?

When I cover the high dollar bracket races, I'm usually told not to use flashes near the starting line at night. But I too have been in the finals of a race when I staged and noticed what seemed like dozens of flashes going off in the corner of my eye. While I might not like it, it's just something you have to put out of your mind and concentrate. And of course, that also precludes us from having any final round photos.

For now though, as Bill said, I'd like to see it duplicated.

Re: Question for Jeff Foster and Dave Kommel
 

One of my favorite final round shots was at the 2001 IHRA Bracket Finals at Darlington. Set the camera on the wall and got them while staging with an 8 second exposure. Wish it was still around, but after a hard drive crash and then server changes at IHRA, a lot of old archived stuff is gone.

Re: Question for Jeff Foster and Dave Kommel
 

[ame="http://www.youtube.com/watch?v=M9h_IGDhxxs"]2011 NHRA Winternationals Super Stock Round 1 - YouTube[/ame]

19 minutes in.

The photographer is about even with the back of the Camaro. Flash double flashes and red light immediately comes on. If it was the cause the camera was not in line with the starting line.

Coincidence?

This was 2 years ago....

Re: Question for Jeff Foster and Dave Kommel
 

We had a pretty good debate about that 2 yrs ago, see Red Light Answer thread a few post down.

Re: Question for Jeff Foster and Dave Kommel
 

Jody, the multiple flashes are called "Burst Flash" and they are used in high speed photography. During the burst flash, the flash fires several bursts in a single exposure.

Re: Question for Jeff Foster and Dave Kommel
 

That would be incorrect. The flash is only firing once during each exposure.

Re: Question for Jeff Foster and Dave Kommel
 

Meant multiple expoure; we use burst flash in the lab and during testing.

Re: Question for Jeff Foster and Dave Kommel
 

Never say never.....but...

I have been around drag racing for going on 50 years and I can never recall seeing NHRA rerun a final round for any reason at a national event

It also seems amazing that the powers that be could decide in such a short amount of time to rerun this round as they did.....

I could easily recount starting line redlight issues going back many years ago.....NO reruns were granted....period...

Re: Question for Jeff Foster and Dave Kommel
 

Rich, not likely to happen for you or I, or Sammy. :-)

Re: Question for Jeff Foster and Dave Kommel
 

Rich, It looks like an admission of guilt, doesn't it?

So there actually IS a problem?

Re: Question for Jeff Foster and Dave Kommel
 

I agree Mark...

And Ed we have to get there to find out....LOL

Jimmy Defrank is still a heck of a good drag racer and deserving of congratulations for winning two eliminators at one race.....

His record speaks for itself......Wins...Titles....they don't come easy....

Re: Question for Jeff Foster and Dave Kommel
 

I just found out there is a video of this and being the video guy that I am I checked it out and here's what I found:

Here's the frame right before the red light comes on:

http://i633.photobucket.com/albums/u...pse471b34b.jpg


Here's the next frame when the red light starts to come on:

http://i633.photobucket.com/albums/u...psfb4cbd13.jpg


Here's the next frame when the red light comes on fully:

http://i633.photobucket.com/albums/u...ps681ea512.jpg


And here's the next frame after the one above:

http://i633.photobucket.com/albums/u...psb6ed538c.jpg


It's hard to tell by just looking at the photos, but in the last frame you can see the reflection of the flash off of the left front corner of the car.

You need to download each picture and scroll through them and it's easy to see. I just use Windows Picture and Fax Viewer and use the right arrow to go to the next picture.

If I were a betting man, which I am, I would bet the camera that took the picture has the capability to trigger external flashes. And to trigger the external flashes the camera uses infrared.

I don't know how external flashes work, but it makes sense that you would have to send out a signal from the camera to the external flashes before the actual flash happens so the flashes are in sync.

The video has a frame rate of 30 frames per second. Which means each frame is .033 seconds apart.

So I believe my hypothesis was correct in my post yesterday.

Re: Question for Jeff Foster and Dave Kommel
 

Look at the O'Reilly sign at the right hand top corner on the sign. Then looking at the passenger side of the car about where the parking light is. According to this the car hasn't moved in any of the four pictures...Just an observation....

Re: Question for Jeff Foster and Dave Kommel
 

Toby, if i'm ever involved in a close race (which is not likely) i'm going to hire you for your (DSI) Drag Scene Investigation, very through. Good job counselor.

Re: Question for Jeff Foster and Dave Kommel
 

If you step through frame by frame on the Mason incident video http://youtu.be/M9h_IGDhxxs you can clearly see the camera flashes, and they do not coincide with the red light coming on. The red light comes on *after* the camera flashes, and the the pre-stage and stage bulbs go out AFTER the red light comes on.

In the Brand incident http://youtu.be/3A5BIAz6W2w there does not appear to be any camera flashes involved, and you're dealing with a footbrake car that staged solidly and then came up against the converter, so you are definitely not dealing with an issue of rocking back out of the beams. Once again, the red light comes on BEFORE the pre-stage and stage lights go out.

This issue has also occured at a track in the east in bracket racing, and we've seen similar things happen in the Pro categories.

Re: Question for Jeff Foster and Dave Kommel
 

[QUOTE=Michael Beard;370036]If you step through frame by frame on the Mason incident video http://youtu.be/M9h_IGDhxxs you can clearly see the camera flashes, and they do not coincide with the red light coming on. The red light comes on *after* the camera flashes, and the the pre-stage and stage bulbs go out AFTER the red light comes on.

If you're going frame by frame wouldn't the red light have to come on after the camera flash? I wouldn't expect it to come on during the flash.

Re: Question for Jeff Foster and Dave Kommel
 

Good point. The camera is stationary, on the ground, so any movement of DeFranks car should be obvious.

Re: Question for Jeff Foster and Dave Kommel
 

Step through the Mason video. The red light comes on 8 frames after the first flash, and 5 frames after the second flash. That's not just "after", that's a *significant* delay. Also, it's been noted that each frame represents a fair amount of time. The timing system is dealing in thousandths of a second, so I would imagine that it IF the flash was the culprit, it is very possible that its results could appear in the same frame, if not the very next frame. 5 frames? Don't think so. Again, it also appears that there aren't any cameras involved in Brand's incident. Camera flashes may just be a coincidence.

None of it explains why the red light comes on BEFORE the pre-stage and stage lights go out in each instance.

A poster on DRR mentioned they had this problem frequently at their home track:
We had a different issue at the bracket finals at Rockingham a couple of years ago. We had numerous errant runs. I was announcing and noted the anomolies before racers even got to the tower to complain. We stopped and replaced one or more photocells on the starting line (that had just been replaced a week or two before). Had problems with the Stage beam hanging so bad it wouldn't go out at all. We turned off Stagelock, and had no more problems. Weird things happen. Maybe we think they shouldn't happen, and we maybe we think the solutions shouldn't be the solutions. Doesn't change the facts.

The most bizarre thing I've ever seen is having R/T's, all incremental times and mph matching other timeslips and making sense, but having the finish ET being off by about two tenths of a second, and the MOV likewise showing about two tenths despite the cars being separated by thousandths. It happened multiple times at the same event, with different cars. How or why it happened, I have no idea, but the only plausible explanation I could come up with was that somehow the finish line sensor "missed" the front wheel, and was triggered by the back tires. A car length was roughly the amount of ET that was "missing".

Re: Question for Jeff Foster and Dave Kommel
 

Like I said, I don't know much about external flashes. Cameras also use infrared for autofocusing. The DeFrank red light could be a case of the camera autofocusing before taking the photo. I don't know if it would take that long to fire an external flash.

As for the Mason red light, there are also three other photographers on that side of the rail. Maybe one of their cameras caused it by autofocusing.

It looks the photographer has to be in the right spot and take the picture at the right time for this to happen. It sure looks like there is some infrared coming from somewhere that is causing this. There definitely needs to be some testing to see what is going on so it doesn't happen again. They need to to get all the photographers together at some point during an event and have them take pictures at different angles to see if they can consistently cause this. Maybe there needs to be a car in the beams for it to happen. If they can't get it to happen then it must be the timing equipment.

As for the Brand red light, the footage doesn't show if there is a photographer on the rail or not. It could be caused by autofocusing as well.

Re: Question for Jeff Foster and Dave Kommel
 

Modern DSLR's do not use infared for focusing.

Re: Question for Jeff Foster and Dave Kommel
 

Do all photographers at the track use modern DSLRs?

And what about external flashes? How long of a delay is there after pressing the shutter and the flashes going off? Is this delay adjustable?

It's possible to have the internal flash off and still be sending a signal to the external flashes, right?

Re: Question for Jeff Foster and Dave Kommel
 

Does anyone know if this has happened in the super gas/comp classes?

Re: Question for Jeff Foster and Dave Kommel
 

99% are using modern DSLR's. You might have friends and crew shooting with point and shoot cameras that use infrared focusing.

When you talk about external flash, I assume you actually mean remote flash. The on-camera flash units we use do have infrared, but it only functions to help the camera focus in very low light situations. Auto-focus is based on contrast and when there is not enough light for the camera to discern contrast, it uses the flash to help it focus. In the Dan Mason situation (daylight), there should not be any infrared at all, so if the photographer (possibly me) caused the redlight, it had to be flash and not infrared. Also, if the flash is turned off, there is no infrared in any situation.

Remote flashes are triggered by a cable, a radio slave unit or they can be triggered by the flash of the on-camera flash. No infrared is involved.

Shutter lag in modern DSLR's is very short, somewhere in the 200ms range and is not adjustable. The flash should fire instantaneously when the shutter opens.

Re: Question for Jeff Foster and Dave Kommel
 

I'm not sure about this exact situation, but at the Dallas national last year, the final two pairs of super comp in round 2 had to be rerun. This was because the tree dropped and everything was good. No incremental times/final times or rts. All zeroes and no winlight. Very strange deal.

I think we are putting a bit too much trust in the timing equipment itself. At brackets at the Texas Motorplex, there was a flaw in juniors. Every once in a while the dial ins would be correct but the difference in dial ins would be cut in half in the race. (I.e a 7.90-8.70 race, the 7.90 car's tree would drop just .4 seconds after 8.70 car's tree) this happened multiple times throughout the year. Just a weird nuance.

What happened to the "big news" that compulink was supposed to announce after the winters. I guess that's on hold for now. Also, weren't they testing a new beam for the starting line last year at Denver?

Austin Williams
464Q S/C STK

Re: Question for Jeff Foster and Dave Kommel
 

There are remote flashes that are triggered by infrared.

Here's a quote I found on the web:

"Because the Nikon/Canon flashes are communicating with infrared light, (as opposed to radio signals) you will need to have your remote flashes in line-of-sight of the controller flash."


It's looking more and more like it's a glitch in the timing system, but as long as they have the photographers to blame, there's no need to fix it.

I think you photographers need to get together with Jeff, or whoever's in charge of the timing system, and do some testing and see if you can make it happen. If it is the flash, you should just be able to fire the flash right up next to the hole in the box and it should trigger the sensor.

If you guys are able to do some testing I hope you will share the results here.