Question for Jeff Foster and Dave Kommel

Toby Lang · 02-17-2013, 11:27 PM

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?

Winklovic · 02-18-2013, 12:01 AM

Might it be the infrared focusing cameras use?

Don Kennedy · 02-18-2013, 12:47 AM

Quote:

Originally Posted by Toby Lang

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?

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

SSDiv6 · 02-18-2013, 09:40 AM

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.

340Cuda · 02-18-2013, 10:37 AM

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

Dave Kommel · 02-18-2013, 11:31 AM

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.

SSDiv6 · 02-18-2013, 12:25 PM

Quote:

Originally Posted by 340Cuda

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

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.

larry dowty · 02-18-2013, 12:33 PM

toby what happened to ask that ?

Bill Koski · 02-18-2013, 12:52 PM

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?

Toby Lang · 02-18-2013, 08:14 PM

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.

02-17-2013, 11:27 PM	#1
Toby Lang VIP Member Join Date: Jan 2002 Location: Auburn, WA Posts: 2,133 Likes: 2 Liked 2 Times in 1 Post	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?

02-18-2013, 12:01 AM	#2
Winklovic Member Join Date: Jun 2010 Location: Winnipeg, Manitoba Posts: 270 Likes: 3 Liked 29 Times in 8 Posts	Re: Question for Jeff Foster and Dave Kommel Might it be the infrared focusing cameras use? __________________ Brent Mazur Winnipeg, Manitoba

02-18-2013, 09:40 AM	#4
SSDiv6 VIP Member Join Date: Feb 2003 Location: Glendale, Arizona Posts: 2,990 Likes: 690 Liked 1,454 Times in 542 Posts	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.

02-18-2013, 10:37 AM	#5
340Cuda VIP Member Join Date: Apr 2003 Location: Tulsa, Oklahoma Posts: 1,567 Likes: 3,154 Liked 677 Times in 290 Posts	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

02-18-2013, 11:31 AM	#6
Dave Kommel Member Join Date: Jul 2007 Location: San Dimas CA Posts: 143 Likes: 2 Liked 2 Times in 1 Post	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. __________________ Dave Kommel

02-18-2013, 12:33 PM	#8
larry dowty Member Join Date: Jan 2005 Location: tacoma wa Posts: 281 Likes: 0 Liked 3 Times in 3 Posts	Re: Question for Jeff Foster and Dave Kommel toby what happened to ask that ? __________________ larry dowty 6388 SS

02-18-2013, 12:52 PM	#9
Bill Koski Member Join Date: Dec 2002 Location: Las Vegas NV Posts: 213 Likes: 0 Liked 0 Times in 0 Posts	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?

02-18-2013, 08:14 PM	#10
Toby Lang VIP Member Join Date: Jan 2002 Location: Auburn, WA Posts: 2,133 Likes: 2 Liked 2 Times in 1 Post	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.