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Old Nov 24, 2011, 7:42 AM   #21
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Based on what I've been able to find out, many if not all states require that educational facilities comply with the Recommended Practice on Lighting for Educational Facilities, ANSI/IESNA RP-3-00 published by the Illuminating Engineering Society of North America. The publication is not available online, but excerpts from it are wildely available on various websites, including those that concern lighting in gymnasiums, one of which is here. It specifies the minimum lighting for particular activities as well as the uniformity of that lighting.
Did you read it (the page "here" pointed to)? ;-)

For high school basketball, you can have areas that are 2.1 times as bright as the recommended lighting level. For elementary, club and recreational, you can have areas 3 times as bright as the recommended level for basketball.

When you look a volleyball (the sport the OP of thread is asking about shooting), it doesn't distinguish between elementary, club and recreational, and you can have areas 3.5 times as bright as the recommended level.

The Uniformity Max/Min column in the page you posted a link to is a ratio. But, it's expressed as a single number by the IESNA. You can find an explanation of how that works on this page:

http://resodance.com/ali/uniratio.html

Also, light from many skylights is not going to be focused by the time it's at the floor level, as it's going to diffuse, especially when smaller skylights are used, just in the way light from fixtures tends to diffuse.

So, I can see where could have lots of cases where some skylights may be used but still allow you to be within the levels specified by the IESNA for lighting consistency, yet cause exposure inconsistency and white balance issues, as observed by JohnG and jdnan (who both shoot sports).

I don't shoot much sports at all, but when I have shot basketball in a gym in my area, I've seen the same thing, where some spots in the gym are brighter than others, with white balance changes between areas (probably because of few windows higher up on one side of the gym)

IOW, the observations of some areas between a full stop different than others in the basketball gym example posted by jdnan would be within the allowed limits, even if they were following those recommendations to the letter.

If shooting volleyball, closer to a 2 stop difference would be allowed (you can have areas that are 3.5 times as bright as the recommended level for Volleyball), according to the page you posted a link to.
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Old Nov 24, 2011, 9:05 AM   #22
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So we've gotten past the question of whether or not there are standards, and now we're discussing how to interpret them. I guess that's progress.

Yes, I have read the webpage I linked to, along with some others. The differences in the specifications between Basketball and Volleyball are inconsequential, I think, as are the distinctions between different levels of play for Basketball but not for Volleyball, because I think it's unlikely that any school would have different lighting systems for different sports. The table lists the minimum lighting levels for different activities, so they would probably install a single system that met the most stringent requirement (that for Basketball), rather that install a system for the least stringent (that for Volleyball) and have supplimental lighting systems for other activities. At the levels we're talking about, too much light isn't going to have adverse effects. That is, Basketball lighting for a Volleyball game isn't going to pose a problem.

Also, it's important to remember that as you double the distance light must travel, the level of that light will be quartered. The court surface directly below a light fixture will be better lit than the court surface that is midway between two light fixtures. That's what the uniformity criterion is about. In other words, you can't put up two very bright lights, one over either side of the court, because the level of light in the middle of the court will be significantly less than directly below either of the two lights. So that specification is more about how far apart lighting fixtures must be placed in order for the court surface to be uniformy lit. And if the court is uniformly lit, then exposure won't change much as you pan on a subject traveling the length of the court.

Also, the author of the link you provided seems to be trying to make a lot of hay about "initial" vs. "maintained" lighting levels, by saying "current lighting industry techniques for predicting maintained levels makes the (questionable) assumption that the distribution of the light does not change over the maintenance cycle of the lighting system". Everything I've read on the subject acknowledges that lighting systems degrade up to 25% over their expected life, and that the lighting industry as a whole agrees that a lighting system as installed must exceed the requrement by at least that much.
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Old Nov 24, 2011, 10:25 AM   #23
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TCAV - at the end of the day, we're back to the same problem when it comes to discussing sports shooting - you're really not speaking from the same experience the rest of us are. Both jdnan and I have indicated we shoot in gyms that have non uniform light conditions. Yet you inanely continue to argue we can't possibly be right. Why on earth is it so important for you to argue about these things? The difference between jdnan, myself and you is jdnan and I are speaking from real world experience - not theory. The mere fact that you seem to insist conditions we have encountered cannot possibly exist because of what you THINK is quite humorous. You're simply wrong. Give up this silly argument and move on and enjoy your Thanksgiving.
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Old Nov 24, 2011, 10:31 AM   #24
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So we've gotten past the question of whether or not there are standards, and now we're discussing how to interpret them. I guess that's progress.
Incorrect again. The "standards" are required only for educational instruction and not for sporting activities. The link to the document you posted is simply an IES recommendation and is not part of an ANSI standard. There are no ANSI standards for sport venues that schools are required to follow. I was a lighting consultant for 5 years, early in my professional career and was a member of the IES. Your assertions are simply incorrect when it comes to sporting venues:

ANSI/IESNA RP-3-00

Lighting for Educational Facilities


This Recommended Practice addresses lighting needs of all of educational facilities from preschool to continuing professional development. Its scope is restricted to learning and study activities, and associated circulation spaces. (The IESNA Lighting Handbook and other Recommend Practices contain guidance on lighting administration areas, sports facilities, or residential accommodations on school and college campuses.)

This is straight from ANSI web site: http://webstore.ansi.org/RecordDetai.../IESNA+RP-3-00
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Old Nov 24, 2011, 10:33 AM   #25
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TCAV - at the end of the day, we're back to the same problem when it comes to discussing sports shooting - you're really not speaking from the same experience the rest of us are. Both jdnan and I have indicated we shoot in gyms that have non uniform light conditions. Yet you inanely continue to argue we can't possibly be right. Why on earth is it so important for you to argue about these things? The difference between jdnan, myself and you is jdnan and I are speaking from real world experience - not theory. The mere fact that you seem to insist conditions we have encountered cannot possibly exist because of what you THINK is quite humorous. You're simply wrong. Give up this silly argument and move on and enjoy your Thanksgiving.
This.
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Old Nov 24, 2011, 10:35 AM   #26
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TCav:

I don't even understand what your whole argument is about. Sports Shooters are telling you that lighting is not consistent in some Gyms with skylights. That has nothing to do with where they're pointing the camera throwing off the metering as you're implying in your comments, since I know from JohnG's posts that he usually goes Manual Exposure in most Gyms.

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Therefore, skylights don't and can't make a significant contribution to the lighting of an indoor venue where sanctioned competitions take place, and will not make a whole lot of difference to a photographer, unless he or she is unlucky enough to point his or her camera directly at one, thereby throwing off the exposure of that particlar frame.
If you look at the sample posted by jdnan when making comments about a stop difference in some areas, he was using manual exposure, too.

Whether or not the difference is "Significant" is a matter for debate. But, if you're shooting at higher ISO speeds, a stop or more can make a big difference in exposure (especially where noise levels are considered). Areas that may have a mixture of lighting types can also throw off white balance. It can be hard enough getting white balance that works well, without mixed lighting entering into the picture.

Now, is there a lot you can do about it? Probably not. JohnG was just pointing out that depending on the type of skylights, it can be a blessing or curse, as you can end up different exposures and white balance in some conditions.

As for if sanctioned sports have to follow those recommendations for lighting, I don't know.

But, I've seen gyms in my areas that had lighting variances, too. I don't shoot a lot of indoor sports, other than some of my nieces and nephews playing basketball every once in a great while, and in one gym they play in, some windows higher up make a difference on one side of the gym, where you have brighter lighting and different white balance in shots taken on that side of it (and I've only shot in the daytime there).

So, if you use manual exposure and white balance settings (as I do), you end up with some darker shots (which means more noise in them), some lighter shots, and different white balance in them, too (as it's not practical to change settings as players are moving from one area to another during play).

Is it significant? Again, that depends on what you view to be significant. Is that difference within the recommended lighting levels you pointed to? That's also a matter for debate.

But, the camera is not as forgiving as the human eye, especially when pushing a camera's limits at higher ISO speeds; and sports shooters like JohnG and jdnan are telling you that they do see lighting variances, and yet you seem to want to argue that's not the case, implying it must be because they're pointing the camera up at lights causing the exposure problems, when they're probably using manual exposure in those conditions when seeing those lighting variances. ;-)
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Old Nov 24, 2011, 11:19 AM   #27
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The law requires that lighting in educational facilities be at certain appropriate levels and must be consistant, skylights or not, daytime or nighttime. Lighting in a gym must be adequate for any time of day, though skylights can provide suplimental light, reducing the requirement for artificial light and energy usage. There's nothing to debate there.

jdnan's sample was taken with the camera pointed up at a light source. That's going to throw off exposure. You don't need to shoot a lot of sports to know that. There's nothing to debate there either.

I conceed that skylights can be either a blessing or a curse (and sometimes both), I suspect as much for light temperature as anything else. But since Greg-M's original post said
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... and not a lot of skylights. ...
I'm not sure what this debate is about either. What I said was this:

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And lastly, indoor sports is indoor sports, regardless of whether it's light outside or dark. You won't see much difference, if any, when shooting during the day vs. at night.
I say something that was on topic and the result is several off-topic posts.

Since Greg-M doesn't have a lot of skylights to contend with, I said that shooting indoors during the day won't be much different than shooting indoors at night. You tell me. Is that what the debate is about?
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Old Nov 24, 2011, 12:05 PM   #28
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Originally Posted by TCav View Post
The law requires that lighting in educational facilities ...
Incorrect, again. See post #24

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Originally Posted by TCav View Post
jdnan's sample was taken with the camera pointed up at a light source. That's going to throw off exposure. You don't need to shoot a lot of sports to know that. There's nothing to debate there either.
You failed to understand the point. The point was the different light levels as clearly seen on the wall, caused by the different light sources, that causes one like the OP to learn to adjust to such thing as skylights, mercury vapor & metal halide mix in the same gym, glow from the scoreboard, etc. This was directly addressing concerns expressed by the OP. It had nothing to do with the angle of the shot.

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I conceed that skylights can be either a blessing or a curse...
Good, then you need to stop contradicting yourself and arguing that the skylights don't make a difference in how the OP learns to shoot indoor sports.



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I say something that was on topic and the result is several off-topic posts.
This is incorrect. The posts following corrected your incorrect assertion (with real world examples), which you continued to defend with incorrect reference to regulations that don't apply to sporting venues, and don't hold true in real world experience EVEN if they did apply.

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Since Greg-M doesn't have a lot of skylights to contend with, I said that shooting indoors during the day won't be much different than shooting indoors at night. You tell me. Is that what the debate is about?
You are now contradicting yourself again. A few skylights or a lot of skylights absolutely impact the shoot, and there is a HUGE difference between shooting indoor during the day or at night, even with a "few" skylights. You just conceded that the skylights can be a "blessing and a curse." When learning to shoot indoor sports such as volleyball, the OP needs to account for this. I shoot indoor sports multiple times a week, during the day, at night, with & without natural lighting.

You are simply incorrect on all points and you are providing inaccurate information to the OP who is trying to learn to shoot indoor sports.
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Old Nov 24, 2011, 12:38 PM   #29
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So, are you saying that, even though Greg-M doesn't have a lot of skylights to contend with, if he wants to shoot an indoor sport during the day, exposure will be different than if he shot it at night?

If your answer is yes, could you please explain how?
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Old Nov 24, 2011, 8:37 PM   #30
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TCav - honestly, stop digging yourself in deeper.
But I'll try to explain this again - if there is a skylight above the court and sunlight falls upon part of the court, the exposure value will be different than if there was no sunlight. Furthermore, because that light is only falling on PART of the court - the exposure for THAT part of the court will be different than another part of the court just a foot away. There is no law requiring this situation cannot happen. It does happen. I fail to see why you're trying to argue that it cannot possibly happen and that it is somehow illegal for a school to allow it to happen. It happens. Two people from two different states are telling you it happens. Why on earth would we make this up? Stop being argumentative about it. Accept the fact and move on.
No one has said definitively the OP will encounter problems. Only that it's possible - you, however keep arguing it is never possible. In point of fact, if there were a lot of skylights things might be better as light would be uniform. With few ones there can be those "windows" on the floor where it's brighter than other areas. All we've been saying is that COULD be the case. Why is that so difficult for you to accept?
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