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Forum: GLOBAL / Editorial / Led-spotlights part of the friction problem solution Login in to contribute
Led-spotlights part of the friction problem solution
OffLine 8a.nu
  2019-04-27 00:00:00    
During Boulder World Cup finals, normally each boulder are lighten up by a spotlight just few minutes before the first person enters. Then the holds are in constant spotlight and get continuously warmed up for some 24 minutes. This means that the conditions deteriorate minute by minute which make the last climber, the winner of the semi, face the worst friction.

It should be noted that in the Olympic finals with eight climbers, the last climber face holds that have been in the spotlight for some 32 minutes. The simple solution to get more fair conditions during the finals is to use led-spotlights.
OffLine Herman
  2019-04-23 22:06:21    
Jens. Again you present your ideas as facts.
You do it all the time. For the last 20 years. And I will continue to point that out (for the last 20 years) because sometimes I'm bored enough to visit this site and stubborn enough to type...

The fact that you think it's logic does not mean that it is true!
Have you actually tested the "fact" that the holds get warmer?
Have you actually tested the "fact" that the friction gets worse?
It sounds plausable, but we should not make changes on just plausable ideas.

Do the holds actually get warmer?
Do conditions continue to get worse all the time? Is there a plateau after e.g 10 minutes?
Is there a minimal distance from the lights before they don't warm the holds anymore?
Does grabbing the holds also make the holds warmer? If so which of the two has the most influence?
OnLine Jens Larssen
  2019-04-24 09:42:16    
It is a fact that climbers always look for cold conditions in the shade. It must be obvious that if you light up the wall with spotlights from few meters, the conditions will deteriorate. We do not have to know if exact how much and if there is a plateau after ten minutes etc as the solution switching to led spot lights is so simple.
OffLine Steve
  2019-04-24 10:10:59    
" It must be obvious that if you light up the wall with spotlights from few meters, the conditions will deteriorate."

True

"... switching to led spot lights is so simple"

Absolutely not true.
OffLine itinerant
  2019-04-24 10:14:27    
Jens - you should really try and understand the difference between "facts" and "claims".
OnLine Jens Larssen
  2019-04-24 10:19:38    
Why is it not easy to switch to led spot lights?
OffLine Robert Kasper
  2019-04-24 10:40:28    
Maybe this is allready the case. Would be surprised if anyone still used incandecent. Lets have a vote amongst the athletes
OnLine Jens Larssen
  2019-04-24 12:08:12    
I have been told that they were not using Led spotlights in Moscow.
OffLine Steve
  2019-04-24 12:31:47    
LEDs are infeasible for large venues.
OnLine Jens Larssen
  2019-04-24 15:14:54    
Please explain why it is not possible to use LED-spotlights from five meters or so. Obviously, the whole arena does not need to use LED-lights.
OffLine Steve
  2019-04-25 13:09:18    
As I said, they are not suited for large venues. For small rooms, it's ok, but for large venues the effects due to their diode nature and discrete spectrum become an issue. You need warm light, ideally from gas lamps, for a good illumination.
OnLine Jens Larssen
  2019-04-25 13:13:33    
I understand but we are talking about spotlights like from five meters. Why would that be a problem with LED.
OffLine Philippe Vaucher
  2019-04-25 14:25:44    
Because the wall would not be illuminated enough, or even if it is it'll look ugly.
OnLine Jens Larssen
  2019-04-25 14:39:32    
Of course it could illuminate enough. How do you mean it would look ugly?
OffLine Philippe Vaucher
  2019-04-25 15:24:45    
See @Steve answer above.
OnLine Jens Larssen
  2019-04-25 19:29:33    
Please explain why LED spotlights from five meters can not do the job? Obviously we are not talking about spotlights from 30 meters distance or so.
OnLine janez miklavčič
  2019-04-25 20:04:43    
See @Philippe Vaucher anwser above.
OffLine Steve
  2019-04-25 20:27:50    
The thing is, in principle it's possible. It's just extremely expensive to make it with good quality. It's not just like replacing a light bulb with an led, like you would do at home. Sometimes it is used for large venues, like some modern soccer stadiums. But they also have the money to cope with all these technological challenges. I've worked in the lighting industry a few years ago and there is really much more around it. I also talked to some international illumination experts and they agree with me that LEDs are not feasible unless you really put in a lot of money, which is not possible for most associations, which is also their personal experience.
OnLine Jens Larssen
  2019-04-25 20:54:31    
I think when it comes to fairness in the Olympic final etc, surely IFSC could take some costs.

I have also been talking to so LED experts and they have told me that lighting up the final boulders from just few meters is easy and not much more expensive in comparison to normal spot lights.

Why should it be expensive to lighten up with LED from just five meters or so? It seems you are talking lightning up the whole arena and sure that would be costly...but again, what is important is the light from like FIVE METERS!
OnLine digdeep
  2019-04-25 21:19:29    
This thread is total nonsense. Basic physics shows why: assuming the climbing holds have perfect absorptivity and the spot light acts as a black body with a radius of 1m and a temperature of 180C, the equilibrium temperature of the holds would be around -50C if they are 5m away. Yes, I did the math, and yes it's approximate, but it goes to show that the amount of heat transfer in this scenario is ridiculously small. There is no factual basis to the claim that illuminating the holds warms them up. The surface temperature of the holds is entirely determined by the ambient temperature.

edit: word
OffLine Steve
  2019-04-25 21:24:09    
"I think when it comes to fairness in the Olympic final etc, surely IFSC could take some costs."

Please appreciate that it is not just some costs, but very expensive. IFSC cannot even pay their live stream commentators, so surely they won't be able to bring up this kind of money, even for the olympics.

"I have also been talking to so LED experts and they have told me that lighting up the final boulders from just few meters is easy and not much more expensive in comparison to normal spot lights."

I am sorry, but I'm afraid that the people you asked are wrong. Please look at my response further above about the technical challenges. It's the diode nature and discrete light spectrum that make it difficult to create a good illumination. As I said, you need warm light and a continuous spectrum, ideally from gas lights, for a good illumination. Even more so, when considering filming. Then you need to take camera interference into account, as most modern cameras are digital, too. If you don't put a lot of money into LED illumination, you will have a crappy picture. I'm sure that IFSC will care more about a good illumination and filming than about competition fairness.

"Why should it be expensive to lighten up with LED from just five meters or so? It seems you are talking lightning up the whole arena and sure that would be costly...but again, what is important is the light from like FIVE METERS!"

Thank you for agreeing with me that LEDs are too expensive. Also, please note that it's not distance, but venue size that matters, i.e. viewer and camera position etc.

@digdeep That's a very interesting insight. Thanks for sharing!
OnLine Jens Larssen
  2019-04-25 23:04:00    
”The surface temperature of the holds is entirely determined by the ambient temperature.”
Spotlights from five meters like in Moscow increases the ambient temperature!

Normal spotlights should lighten up the Venue. The Led spotlights only when more light is needed from five meters. This should increase the cost just marginelly.
OffLine Herman
  2019-04-25 23:59:39    
Jens, this might help!
https://www.8a.nu/images/forum/5237_636918334948815428_Universele_schep_met_steel_van_PP_3col__AA00123864II_01.jpg
OffLine Herman
  2019-04-26 00:00:30    
https://www.8a.nu/images/forum/5237_636918335460138846_Universele_schep_met_steel_van_PP_3col__AA00123864II_01.jpg
OffLine Philippe Vaucher
  2019-04-26 08:17:48    
@Jens: simply ask ~10 competitors what they think about it, and report ALL the results, not just the ones supporting your claim.
OnLine Jens Larssen
  2019-04-26 08:40:05    
I have over the years been talking to many more than 10 competitors and most of them agree that it would be best to start as #1 in the final. Some say they do not care but none said starting last is best.
OffLine Philippe Vaucher
  2019-04-26 09:39:48    
Notice how you switched the subject? I told you to ask them if the lights temperature is a disadvantage for the first guy, but then you talk about starting first or last without reguard to the temperature, which is another subject.

If it's best to start #1 it's mostly because of the mental pressure, not because of the "deteriorating conditions".

Of course if a competitor believes that the conditions deteriorate with time then his mental will suffer and he will not be in the right state of mind.

We are arguing that the conditions do NOT deteriotate significantly for it to be a real factor (friction/temperature is the same wether you start first or last), but psychologically of course anything can happen.
OffLine Philippe Vaucher
  2019-04-26 09:39:49    
edit: removed double post
OffLine Steve
  2019-04-26 09:40:44    
"Spotlights from five meters like in Moscow increases the ambient temperature!"

No.

"Normal spotlights should lighten up the Venue. The Led spotlights only when more light is needed from five meters. This should increase the cost just marginelly."

Please explain how LED spotlights would increase the cost only marginally.
Also, @Jens, you should read up how illumination works. Gas lights and LEDs have roughly the same light temperature. Therefore, the warming of holds is similar. However, the light from gas lights is "warmer" and therefore provides a better illumination.
OnLine Jens Larssen
  2019-04-26 10:02:24    
So what do you say about this piture?
OffLine Steve
  2019-04-26 10:22:17    
@Jens: Please explain how this picture contributes to the discussion.

Also @Herman: agreed!
OffLine TheoR
  2019-04-26 10:37:15    
OK guys, i usualy let this kind of polemic without any intervention knowing how far this can be from reality when non expert speak about topic they don't master…

Just for introduction i'm a thermal expert and i'have worked in the professional LED lighting industry for about 5years.

I supposed your statement for LED is because "LED don't warm-up" or because they "consume less energy". And the last but not least "the diode nature and discrete light spectrum". I have eard this statement so many times...Let me explain what is behind.

1st : Whight light from LED is created from blue chip covered with phosphorus. The Phosphorus is re-emitting part of the light in a continuous spectrum. In fact the white LED technology has a continuous spectrum and it's is the closest to the sun light visible spectrum.

Color randering index can be above 95 which is high end professional lighting.
The DC power supply eliminates flickering problems that you have for many other light sources.
You can have all color temperature (in the white) including warm or cold white.
In fact LED IS USED FOR SPORTS and is one of the best application ! It's suitable for HD camera, some football and basketball stadium already use LED lighting ! Their is great randering including for HD cameras and photgrapher !

IS it going to solved your climbing probelmatic ??! NO !

1st : "LED don't warm-up", is false YES they DO !! They're electronic device and if you wan't to avoid failure you need to maintain the LED Chip below 100°C.
As for ANY light source, part of the energy consumed is transformed into heat and part into light.

2nd : LED "consume less energy", yes but as mentionned by steve for event with camera you need a certain amount of ligh and a certaine randering index (which correspond more or less to a continous spectrum). You'll set-up some LED spots that will consume less energy but that will illuminates the holds with the same amount of light.

The only difference is you'll have less power dissipated into heat near the spot itself !!!
@digdeepjust demonstrate that the IR radiation are negligiible (and forgot about the visible spectrum radiation…).

You might have air slightly colder with LED light but for such events the light heat source is nothing in comparison with the crowd (>100W per person).

If your effect does exist. The only way to make it fair to the athletes is to warm-up the holds before the 1st athlete is climbing. You'll reach an equilibrium (plateau) were the temperature stop rising. I believe this is what is done with the 24minutes warming you mentionned...
OnLine Jens Larssen
  2019-04-26 10:52:40    
@ TheoR: Thank you very much. Just to confirm. You mean that there is no difference in between normal spotlights and a LED spotlights placed like two meters behind the climber resting, in regards heat?
OffLine TheoR
  2019-04-26 11:24:31    
If you ave comparable spectrum and same amount of light (which is most probably the case in regards with what is needed for the cameras)

-No difference from heat absorbed by the holds from the light itself.
-Small difference on the air beeing heated up arounf the spot. Most probably negligible if you compare the heat source genated by the lights with the one generted from the crowd.
OffLine Philippe Vaucher
  2019-04-26 11:29:17    
Jens: now that you admit the conditions do not deteriorate because of the lights, you only need to understand they also don't deteriorate significantly due to friction, and that the only thing left is psychological pressure, which is not something we should fight against IMHO.
OnLine Jens Larssen
  2019-04-26 11:48:37    
Thanks again. I have been talking to my expert again and he agrees with you that the light itself does not heat up the holds. On the other hand he says that the heat created in the ambient by regular spotlights from five meters in comparison to LED is absolutely not negligible after having put on the light for 24 min. He says that we should take notice that the wall itself is overhanging and covered up on the sides. The temperature can be easily measured and he says he would be super surprised if not the temperature would increase like from 20 to at least 23 degrees, next to the wall, after 24 minutes. For a LED spotlight he says the increase would be much less. Do you think he is dead wrong or is it just some kind of misunderstanding going on?
OffLine Steve
  2019-04-26 12:20:03    
@Jens he is wrong, but not dead wrong. As mentioned above, the temperature increase by LED is only marginally less. The reason is, as TheoR mentioned, that LED spots themselves heat up. In fact, large spots, as they would be already needed for 5m distance and camera production quality, require water cooling. That coolant goes into the surrounding and therefore contributes to the ambient heat increase.

Also, please note that while TheoR corrected some statements, he may not have understood the general theme of this discussion, which is to distinguish facts from claims.
Anyway, as you said, with the current lighting situation, the temperature increase can be felt after 24 minutes. But IFSC has already accounted for this fact by setting the bouldering time to 4 minutes max, thus creating fair conditions.
OnLine Jens Larssen
  2019-04-26 13:10:41    
It will take 32 min in Tokyo in between the first starter and the last try for the last starter so it seems your conclusion is based on 4 min?
OffLine Steve
  2019-04-26 14:14:41    
No.
OffLine TheoR
  2019-04-26 14:15:36    
Last answer.

If we are not speaking about the light then yes the LED are going to heat-up the air less.

Some more figures :

-LED doesn't bring avantage regarding the direct heat-up of the holds from light. Which propably does exist has for camera you need a tremedous amount of light...For an order of magnitude more than 4 000 000lm for a basketball stadium !

-When we speak about heating up the air, yes they will heat less. But they will still heat. The problem of the air heating-up during the comp has more to deal with having a properly sized building cooling system for such event (taking into acount lights but also crowd but also all other electronic devices and so on...)

So LED are not bringing a real solution !

My point is, when you have technical topics as this one, most of the post are made by people who don't catch the physics behind, don't bring figures or don't do the math.
If there is a real issue it should be discussed through scientific article based on fact and physic, then the article can't be relayed in 8a.nu. Creating polemic on nothing is just steril.
OnLine Jens Larssen
  2019-04-26 14:34:27    
I totally agree on everything you say and as you see by the headline I have only said that LED-spotlights are part of the solution for which you seem to agreee but to a lesser extent :)

I will suggest IFSC make a research to find out what is most important to improve to make it more fair for the last one out in Tokyo.
OffLine Simon Fonn Storevik
  2019-04-27 12:42:08    
How about a completely different and much easier take on the fairness situation. It doesn't need to be totally fair in the final, as long as the winner of the semi-final gets the best conditions. That would be a fair advantage of winning the semi-fnial.

Now since there seems to be a dispute regarding when its best to start, we could take something from the sport of alpine-skiing. They have an inherent problem with unfair conditions, and there is nothing you can do about it, so they let the best ranked athletes choose their starting numbers.

This could be the solution, let the winner of the semi-final choose their starting position in the final.
OffLine Steve
  2019-04-27 12:48:25    
"I will suggest IFSC make a research to find out what is most important to improve to make it more fair for the last one out in Tokyo."

Seems like you are learning. Great! Research is the best way to get facts straight and refute stupid claims. :D
Pro-tip: Make it a feature interview with someone from IFSC asking how they address fairness and especially how they address light and heat issues.
OffLine Jan V'
  2019-04-29 14:09:22    
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