Design LED Light Box

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So I'm working on a 3" deep overall depth light box with a 1/4" thick milk plastic lens and 1/2" thick bottom. Believe it's like 18"x39" in lens. Will have wished a deeper box and might shoot for another inch but... Designer wanted this thick.

I have already decided on trying first a set of 24" and 36" T-5 high output fluorescent lamps from the outside edges of the lens. There will be a display object in the center on top of the light box, so lighting the center isn't as important. 11,000 lumens side lit = less direct for less overall lumens even with a white interior, but might be enough.

Second option is 6x 36" T-5 lamps 2.3/4" O.C. across the body of the lens for 21,000 Lumens more direct - but you will probably see the lines of light from the lamps thru the lens. Might try a RX-105 Tough Spun between lens and lamp if the direct lamp light isn't too bad for this fix. This might help further disperse but doubt enough.

Dialing in the luminous output with a dimmer at the display unit a bonus for shows dependant on the show ambient lighting needs, believe or think a CFL/LED dimmer will dim a T-5 lamp? Something I have never done before. Fluorescent dimmer?

Third option is back to the parameter side lighting but with 4 node wide LED tape (I really want to try the four node wide tape and bying the 98' spool is cheaper, I'll easily use the rest on other projects, and the followup parts of this project.) https://www.superbrightleds.com/mor...mds-per-ft-high-cri-1-chip-smd-led-2835/3615/
LED tape mounted to the base of the light box vertically around all sides 1" back from the lens. 118" long, 12 watt per foot, 118 watts. 12,906.6 lumens. RS-150-24 Meanwell Power supply for it. Believe I can use a normal Lutron LED/CFL dimmer for dimming this. Or given the Meanwell psu is self adjusting for voltage, would trying to dim with a architectural LED/CFL dimmer not work?

Fourth option isn't viable really... it would be like the luminous output of a 1.5Kw incandescent lamp inside the light box for intensity and non-dimmable - but be really cool. Eight or nine strips of four node LED tape laid across the bottom of the light box with about a 1" spacing. 38,522 lumens but 351 watts and while I could do a SE-450-24 Meanwell PSU, there is no such thing as a LED architectural dimmer type I know of that could dim this. Has to be a dimmer in the display panel if going to dim at all. Even if I went only eight strips wide, it would be over 300 watts. 150 Watts to at best 200 Watts from what I understand is the best LED you can dim with a architectural type dimmer. This short of remote 1-10v control dimmer to a in-fixture or remote controlling PSU dimmer unit that isn't really designed for this purpose I think. Have some of these dimmers with some architectural LED high bay wash light fixtures converted to touring usage.

Fifth option, single node high output normal white tape but say 1" spacing (boring) and have to run the math for lumens and PSU+dimmer as probably option #3 or #4 realistically to work especially with the tough spun gel.
 
Is this a theatrical or architectural project? Do you need good dimming control? If you want really good dimming control at the low end you will want to avoid fluorescent tubes. The dimmable ones still have a minimum power requirement to turn on, so there will be a jump at the bottom of the fade. You also need a dimmable ballast, but these range (typically by cost) in how much jump they have at the low end. LED tape will give you much more control. LEDs will also require a dimmer that does PWM, as analog dimming will cause them to jump intensity at the low end as well. With PWM you can get a really good fade. If you are using a DMX system City Theatrical B series dimmers would handle this for you. As far as the commercial style lutron wall dimmer switches go, they tend to get hot at high wattages and are likely to have a short life if controlling more than a few dozen watts. Some of the wall mount switch dimmers are also not able to give a good fade at the low end, depending on the technology they are utilizing.

More information about how you want to use it, and your technical need and budgetary constraints can help us propose ideas.
 
Display booth trade show light box with I believe some form of motor above it in the center of the light box table. Lamps on all day for dispay, the dimming only a thought about adjusting intensity show to show in ambient lighting for adjusting the output to the light box table. An option not requested but in doing a proper job considered.
So mostly low end control, plug the light box in, set the dimming level for the show and forget. Literally Edison cord in and any control I do is inside the light box a bonus.

Budget none persay, but want carpenter type in ability to power this up and adjust the lighting.
 
You are the king of ghost load. How could you not swing option four.

Also if you didn't go ghost load why not run the PSUs inline for input power and have 4 150w dimmers to control each section of nodes. I know space is an issue and that amount of psu and lights might cool everything so you would possibly have to put an in and out fan in there somewhere too.

I vote option 4 cause it sounds like the build that is going to be the most fun to concept.
 
Being trade show and dimming performance isn't critical it sounds like you could go fluoro or LED. Sounds like budget is your largest constraint.
 
Budget wasn't a constraint, more the depth of the light box.

So I did the 22" and 34" T-5 lamps at the parimiters of the light box lens. Looks good but fab shop didn't supply the lens to once wired by the end of day, and I didn't have any ML-2 flange mout outlets in stock to finish it. Small question about the ML-2 outlet and wiring sticking up within the lighted zone in blocking it some. Otherwise for a light box, there is light coming out, just don't know if sufficient.

Trying to avoid lamps and or LED tape across the field of the lens size - can frost further etc. but it's still fighting the nodes or linear parts of the bright parts of the light from the lens. Next goal would be the four node vertically placd on the parameter of the light box so still there is no lines of bright spots linear to fight against. There is some form of prop installed at the center of the lens so a darker center of the light box isn't important.

Don't know, will see how this above 22" and 34" from the paramiters of the light box works out and go from there. The four node wide and perhaps much wider tape is coming and I'm starting to think of it design wise. Think it important to know about.

Onto LED I-Beams, Modifying power supplies for them, the further light boxes and booths from the other project, a few cable builds, signing into the computer like 100 more lamp serial numbers etc. Down in staff my best fabricator, promised help. Hope I at least get a exploded MR-16/208 power supply power supply person even if three sets of lamps before figuring out there was a problem... I find such people with supervision really ready to learn. Than judge them once supervised and trained. Busy coming week for me.
 
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If budget wasn't an issue, and maybe even if it is - Light Turning films! I believe they have both refractive and reflective.
http://www.luminitco.com/products/direction-turning-films

The T-5 lamps were accepted and was a go in bright enough, how its plugged into the base stand a different story as only +2" inside the box room for output ML-2 socket. Intererested in the above link but not refined in product link for a product. In the works given spacers to go back to my understanding of the design. AKA.. what I wired up didn't have room to wire without spacing in showing thru. How I got it done is amature in finished product - to change. Designer wasn't thinking thru his product and will be changed for how it's plugged in. Sorry to the designer. but a light box with about inside the box 2" spacing between the box and lens is not a good thing for other than side mounted lamps - LED or flourescent.
 
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Intererested in the above link but not refined in product link for a product.

They have some pretty odd stuff and don't publish all their data on the web. So the best bet is call them and tell them what you are up to. I'm pretty sure they know all about light boxes.
 

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