Lighting: Parabolic Louvers vs. Egg Crate

[rexus31]

This topic came up in another thread and I thought it may warrant its own discussion for those that are interested. The older I get (currently 52) the more important good table lighting is. As some of you may know, I've built a couple custom lights. One for my 1950's AMF (similar to an Anniversary) and I recently built a custom light for my Gold Crown I. Both lights used the same lighting source: (8) 5000K 48" Fluorescent T8 bulbs each putting out 2600 Lumens at a CRI of 90 emitting through a couple chrome plated standard egg crate diffusers. When I posted my light in the aforementioned thread, members @DeadStick and @EL'nino pretty highly recommended a set of parabolic louvers to replace the standard egg crates I was using. The idea behind the parabolic louvers is the cells are formed in a way that direct the light to a more focused area compared to the egg crates and they also cut down on glare. I'm all for better lighting and improvements even though I'm not at all sensitive to glare. I play for hours on my table and have never felt eye fatigue. But hey, if the lighting is more focused and more importantly, brighter, I'm in. I went ahead and ordered a set from Amazon. They are more expensive compared to the standard egg crate diffusers at $120 shipped for the pair. I sourced the egg crates from Home Depot for $75 (pair) out the door when I built my light.

I'm not real convinced the parabolic louvers are an upgrade in brightness. Sure, there's less light around the rest of the room with them, but that was never a concern for me. I actually think the light is a little brighter with the egg crates. Due to the nature of the egg crates design, each bay of the light covers more table surface than the parabolic louvers. I tested this by covering one of the bays with cardboard. The egg crates clearly allow more light up/down table vs the parabolic louvers. I think this contributes to a little brighter playing surface. The pics below were taken with my iPhone with no filtering used. I think I'm going to return these and use the $120 to donate in my next Ring Game.

 

[bignick31985]

I used the silver egg crates on my current light and it's much easier to look across the light while sitting down. Had black painted egg crates before but the silver ones spread better and appear brighter.

While playing you don t have the brightness blasting you like some of the perimeter lights. At Derby there are 7 perimeter lights on the TV table and Im only 38 and can barely stand to watch the TV table for a while match. Too damn bright and no diffusers to soften it visually. I'd prefer to watch from the 2nd story seating.

 

[Bob Jewett]

I actually think the light is a little brighter with the egg crates. ...

Basic light meters on Amazon cost about $30. They claim better than 5% accuracy. The good ones are filtered to have the correct visible light response. Even a poor one should let you do accurate comparisons if you use the same kind of bulb.

Here is a long thread about lighting -- basically the AZB FAQ on lighting -- including the results of measurements:

Lighting FAQ

After reading many questions on the forums I wanted to post this as a future reference in order to help answer any basic questions regarding lighting. I work in the lighting industry and wanted to help as there seems to be many basic questions...

forums.azbilliards.com

 

[fjk]

This topic came up in another thread and I thought it may warrant its own discussion for those that are interested. The older I get (currently 52) the more important good table lighting is. As some of you may know, I've built a couple custom lights. One for my 1950's AMF (similar to an Anniversary) and I recently built a custom light for my Gold Crown I. Both lights used the same lighting source: (8) 5000K 48" Fluorescent T8 bulbs each putting out 2600 Lumens at a CRI of 90 emitting through a couple chrome plated standard egg crate diffusers. When I posted my light in the aforementioned thread, members @DeadStick and @EL'nino pretty highly recommended a set of parabolic louvers to replace the standard egg crates I was using. The idea behind the parabolic louvers is the cells are formed in a way that direct the light to a more focused area compared to the egg crates and they also cut down on glare. I'm all for better lighting and improvements even though I'm not at all sensitive to glare. I play for hours on my table and have never felt eye fatigue. But hey, if the lighting is more focused and more importantly, brighter, I'm in. I went ahead and ordered a set from Amazon. They are more expensive compared to the standard egg crate diffusers at $120 shipped for the pair. I sourced the egg crates from Home Depot for $75 (pair) out the door when I built my light.

I'm not real convinced the parabolic louvers are an upgrade in brightness. Sure, there's less light around the rest of the room with them, but that was never a concern for me. I actually think the light is a little brighter with the egg crates. Due to the nature of the egg crates design, each bay of the light covers more table surface than the parabolic louvers. I tested this by covering one of the bays with cardboard. The egg crates clearly allow more light up/down table vs the parabolic louvers. I think this contributes to a little brighter playing surface. The pics below were taken with my iPhone with no filtering used. I think I'm going to return these and use the $120 to donate in my next Ring Game.

When you going to finish that wall? It's starting to bother me.

 

[FairladyZ]

The footprint is what is key here; casting as much of the light downward onto the table. In the photo, what's on the table surface doesnt look much different as far as shadows around the balls and brightness. Unless light is being projected through lenses, you won't get a higher concentration of light in any given place using basic reflective / refracting; you're basically just guiding the light; not unlike guiding water through a shower head....but just guiding it doesn't intensify it. Like you said, pay more attention to the backround; walls in particular in the two pics....but what's showing on the table surface looks the same. With light guiding (louvers), it's all aimed at the table; leaving little ambient waste; IE, the walls appear darker. You can then use separate lighting for the rest of the room or leave the rest of the room darker (which is what I like)....so I thumbs up the louvers for controlling the wasted light.

I like the refracted light better....Just my worthless 2 cents.

 

[rexus31]

When you going to finish that wall? It's starting to bother me.

It's finished...lol!

 

[DeadStick]

Basic light meters on Amazon cost about $30. They claim better than 5% accuracy. The good ones are filtered to have the correct visible light response. Even a poor one should let you do accurate comparisons if you use the same kind of bulb.

Here is a long thread about lighting -- basically the AZB FAQ on lighting -- including the results of measurements:

Lighting FAQ

After reading many questions on the forums I wanted to post this as a future reference in order to help answer any basic questions regarding lighting. I work in the lighting industry and wanted to help as there seems to be many basic questions...

forums.azbilliards.com

There are also lots of iPhone apps to measure lumens and lux. I use this one, it's pretty accurate:

‎Lux Light Meter Pro

‎Light Meter is a 2-in-1 light intensity (lux) and exposure meter with customizable settings. Whether you want to capture the perfect photo or optimize lighting in any space, Light Meter provides professional-quality readings right on your phone. Forget about expensive professional equipment...

apps.apple.com

 

[DeadStick]

This topic came up in another thread and I thought it may warrant its own discussion for those that are interested. The older I get (currently 52) the more important good table lighting is. As some of you may know, I've built a couple custom lights. One for my 1950's AMF (similar to an Anniversary) and I recently built a custom light for my Gold Crown I. Both lights used the same lighting source: (8) 5000K 48" Fluorescent T8 bulbs each putting out 2600 Lumens at a CRI of 90 emitting through a couple chrome plated standard egg crate diffusers. When I posted my light in the aforementioned thread, members @DeadStick and @EL'nino pretty highly recommended a set of parabolic louvers to replace the standard egg crates I was using. The idea behind the parabolic louvers is the cells are formed in a way that direct the light to a more focused area compared to the egg crates and they also cut down on glare. I'm all for better lighting and improvements even though I'm not at all sensitive to glare. I play for hours on my table and have never felt eye fatigue. But hey, if the lighting is more focused and more importantly, brighter, I'm in. I went ahead and ordered a set from Amazon. They are more expensive compared to the standard egg crate diffusers at $120 shipped for the pair. I sourced the egg crates from Home Depot for $75 (pair) out the door when I built my light.

I'm not real convinced the parabolic louvers are an upgrade in brightness. Sure, there's less light around the rest of the room with them, but that was never a concern for me. I actually think the light is a little brighter with the egg crates. Due to the nature of the egg crates design, each bay of the light covers more table surface than the parabolic louvers. I tested this by covering one of the bays with cardboard. The egg crates clearly allow more light up/down table vs the parabolic louvers. I think this contributes to a little brighter playing surface. The pics below were taken with my iPhone with no filtering used. I think I'm going to return these and use the $120 to donate in my next Ring Game.

Sorry to hear you aren't happy with the parabolic louvers. Personally, I like the way a bright table "pops" in a room that's darker around the perimeter, and I'm very sensitive to side glare, but different strokes for different folks.

It's hard to compare two different iPhone pics, because the phone is auto-adjusting exposure. There are advanced camera apps that let you lock an exposure setting. That caveat aside, I ran a digital luminosity meter over your two pics above, and the table surface in your parabolic pic is about 4% brighter.

 

[garczar]

Sorry to hear you aren't happy with the parabolic louvers. Personally, I like the way a bright table "pops" in a room that's darker around the perimeter, and I'm very sensitive to side glare, but different strokes for different folks.

It's hard to compare two different iPhone pics, because the phone is auto-adjusting exposure. There are advanced camera apps that let you lock an exposure setting. That caveat aside, I ran a digital luminosity meter over your two pics above, and the table surface in your parabolic pic is about 4% brighter.

I like the darker surrounds myself. Both have awesome visibility.

 

[pt109]

 

[Bob Jewett]

I like the darker surrounds myself. ...

In old time pool halls it was sometimes better not to see what was off in the dark.

 

[iusedtoberich]

I play in a room that just got all new perimeter lights. They have horrible glare. IDK what is going on, but I feel super uncomfortable there. I don't recall feeling like this ever before in all my years of playing. I may try a hat next time I go, and I haven't worn a hat since I played T-ball.

 

[Nick B]

Not a Lighting Engineer (Automation & Control) but I've done a little bit of lighting work over the years. I expected about 5~10% improvement with parabolic type. Basically getting the light that used to wash onto walls back to table. I also seem to see less shadowing with parabolic. Again what I expected. Note height is a factor. These "lenses" are generally designed around 10 foot ceiling. I suspect your working height is less so performance upgrade is less because of that, The egg crate would really push the light wider if up a couple of feet.

Your iris and camera phone are both wonderful devices. You could double the foot-candles (lumens) and swear it was only 25% better.

 

[rexus31]

All this talk about lux meters and measurements piqued my curiosity so I downloaded a lux meter app on my iPhone and took some measurements. I measured 15 points on the table with the silver egg crate diffusers, parabolic louvers and no diffusers. Below are the results. On average, the parabolic louvers produced 3.4% brighter light than the egg crate diffusers while no diffusers produced 8.6% brighter light vs the parabolic louvers and 12.5% brighter light vs the egg crate diffusers.

It is clear the egg crates facilitate each bay of the fixture to spread more light across the entire table as evidenced by the slightly higher lux readings at the head and foot of the table vs the reading with the parabolic louvers. The parabolic louvers do provide slightly brighter light at the rails on the head string and foot string vs the egg crates. At the end of the day, I think it's splitting hairs on which light diffusion produces brighter light and it comes down to personal preference. If you are sensitive to glare and prefer darker surroundings with the light directed primarily on the table, the parabolic louvers are for you. If those conditions aren't important to you, you can't go wrong with the silver egg crate diffusers. I am not sensitive to these conditions so I think I'll be sticking with the egg crates.

 

[DeadStick]

I play in a room that just got all new perimeter lights. They have horrible glare. IDK what is going on, but I feel super uncomfortable there. I don't recall feeling like this ever before in all my years of playing. I may try a hat next time I go, and I haven't worn a hat since I played T-ball.

Same. Love their design, but hate their glare. They light up the whole room. If some company offered one with parabolic louvers I’d probably buy it.

 

[Bob Jewett]

All this talk about lux meters and measurements piqued my curiosity so I downloaded a lux meter app on my iPhone and took some measurements. ...

Impressive. Where I play the ends of the table are down around 150 lux. A six ball on the far end rail is a challenge.

 

[DeadStick]

All this talk about lux meters and measurements piqued my curiosity so I downloaded a lux meter app on my iPhone and took some measurements. I measured 15 points on the table with the silver egg crate diffusers, parabolic louvers and no diffusers. Below are the results. On average, the parabolic louvers produced 3.4% brighter light than the egg crate diffusers while no diffusers produced 8.6% brighter light vs the parabolic louvers and 12.5% brighter light vs the egg crate diffusers.

It is clear the egg crates facilitate each bay of the fixture to spread more light across the entire table as evidenced by the slightly higher lux readings at the head and foot of the table vs the reading with the parabolic louvers. The parabolic louvers do provide slightly brighter light at the rails on the head string and foot string vs the egg crates. At the end of the day, I think it's splitting hairs on which light diffusion produces brighter light and it comes down to personal preference. If you are sensitive to glare and prefer darker surroundings with the light directed primarily on the table, the parabolic louvers are for you. If those conditions aren't important to you, you can't go wrong with the silver egg crate diffusers. I am not sensitive to these conditions so I think I'll be sticking with the egg crates.

Nice measurements. 1600 in the center down to 800-850 on the ends is quite a dropoff - what type of bulbs do you have in there? And did you angle your phone to point directly at the center of the light in each position?

My flat panel LEDs produce a more even light end to end as I recall - will try to measure when I return home from a business trip.

 

[rexus31]

Impressive. Where I play the ends of the table are down around 150 lux. A six ball on the far end rail is a challenge.

Wow! My eyes couldn't fade that!

 

[rexus31]

Nice measurements. 1600 in the center down to 800-850 on the ends is quite a dropoff - what type of bulbs do you have in there?

The fixture has (8) 5000K 48" Fluorescent T8 bulbs each putting out 2600 Lumens at a CRI of 90; 20,800 total Lumens.

And did you angle your phone to point directly at the center of the light in each position?

I did not. The phone laid flat at each measuring point.

My flat panel LEDs produce a more even light end to end as I recall - will try to measure when I return home from a business trip.

I debated going LED when I built the light but decided against it because I used these bulbs in a previous light I built and I liked the lighting. I wasn't interested in trial and error with LED's so I stuck with what I knew. When the ballasts go I will probably rewire and go with frosted LED tubes.

 

[iusedtoberich]

All this talk about lux meters and measurements piqued my curiosity so I downloaded a lux meter app on my iPhone and took some measurements.
....snip...

Which app did you download? I have one called "Light Meter" on my iPhone and I'm getting about 470 Lux in the brightest part of my table. I have qty 2: 2x4 LED panels without any grates, flush mounted on the ceiling.