Not sure what to do with these...

[Pixels Are Bad Mmmkay?]

We have a friend who acquired some indoor backlit sign cabinets from a company auction. He owed us a favor and since he got them incredibly cheap, he gave them to us to do with as we see fit. So we decided to use one to hang in our shop window. These cabinets seem to be pretty high end and have a snap frame that goes all the way around for changing out graphics. They are manufactured by a company called MDI Worldwide and they measure 42" x 36" x 4" deep. They have a removable 1/8" polycarbonate or acrylic face. The lighting array consists of 8 T8 flourescent bulbs.

The problem is I'm really not sure what kind of print to use on this type of cabinet as it seems to show hot spots really bad. I'm guessing this type of frame is more suitable for posters. We would like to hang it inside our front window and use it like a standard backlit with adhesive graphics applied to the face or possibly both faces. Is there any good way to do this and diffuse the hot spots at the same time? I was thinking maybe a digital print on Oracal 3651 applied to the front of the face and then to the back side of the face in reverse. Or is there a better way? We are also considering replacing the T8 setup with LED instead if we must. I'm just not sure what option would be the best. Any opinions?

 

[Gino]

Pan face.

 

[J Hill Designs]

these will probably work to cut down the hotspots:

http://1000bulbs.com/product/247/PLAS-100100.html

 

[studebaker]

"Frosted Glass" Vinyl is a great diffuser for the back side. Consider LED's on the sides of the cabinet pointing toward the center. More light bounce / refraction before exiting through the face.

 

[studebaker]

Also, if you want to stay with the Fluorescent tubes, you can apply a thin strip of aluminum tape on the front of the tubes to reflect excessive light to the rear of the cabinet.

 

[Gino]

Also, if you want to stay with the Fluorescent tubes, you can apply a thin strip of aluminum tape on the front of the tubes to reflect excessive light to the rear of the cabinet.

Now, that's a neat idea. Many years ago, metal strips were used to run wires in front of lamps and it worked fine, so this will probably save ya from having to buy a pan face.

 

[Gino]

Also, if you want to stay with the Fluorescent tubes, you can apply a thin strip of aluminum tape on the front of the tubes to reflect excessive light to the rear of the cabinet.

:Oops: double post...... but it's still a neat idea.

 

[Pixels Are Bad Mmmkay?]

Thanks for the tips. I'll keep pondering this until I come up with the best possible solution. Pan faces are a little more expensive than what we would prefer to go with, so I will try the etched glass vinyl first, then the aluminum strips.

One other scenario I wondered about was if we remove the face from the back side (not sure we even want it double sided) and replace it with aluminum finish ACM if the aluminum would reflect enough light back toward the front of the cabinet to kill some of the hot spots. I may throw some aluminum foil in there temporarily and see if it makes much difference before cutting up a perfectly good piece of ACM panel.

 

[J Hill Designs]

I would use light enhancement film before mill finish acm

 

[Pixels Are Bad Mmmkay?]

I would use light enhancement film before mill finish acm

What is light enhancement film? I'm not familiar with this.

 

[Gino]

The general rule of thumb is... the lamp needs to be about 4" or 4.5" away from the face. Given the size of the lamp and the placement, you're not more than 3" away and regardless of what you do in back of the lamps, the front will still remain too close. You either need to get the face further away [pan face] or as mentioned, cover the light nearest the face. No matter how you try to diffuse with fancy faces or vinyl, the lamps aren't gonna move and you're going to continue to have these hot spots, just maybe not as bad in some cases as others.

Being a sign shop and trying to look your best, I would certainly not put a cut-corner remedy in your own shop. You wanna be an inspiration, not a casualty.

 

[John Butto]

Get some polyester backlit film and a clear 1/16" acrylic and I am assuming the piece you already have is white and sandwich the backlit film between them. The white plastic and white polyester will diffuse the light enough in most cases.

 

[Pixels Are Bad Mmmkay?]

Being a sign shop and trying to look your best, I would certainly not put a cut-corner remedy in your own shop. You wanna be an inspiration, not a casualty.

Absolutely. And those are very wise words, I might add.

The more I think about it, I know you're right on all counts. But if I didn't want to go the pan face route, would replacing the lamps with LED's be a good alternative? Right now I'm torn between that, covering the front half of the bulbs with some sort of vinyl, probably chrome polyester, or the pan face.

 

[Pixels Are Bad Mmmkay?]

Get some polyester backlit film and a clear 1/16" acrylic and I am assuming the piece you already have is white and sandwich the backlit film between them. The white plastic and white polyester will diffuse the light enough in most cases.

The "in most cases" is the only thing I would scare me off. These things are hot. If I get a chance I will post a pic later of the cabinet turned on. I'm guessing this may be why the company auctioned them off. Perhaps the performance of the cabinet wasn't up to their expectations for whatever the application was.

 

[John Butto]

My other suggestion is you could get some grow lights and raise some weed for some real money. My idea on how to set them up.

 

[MikePro]

painting the inside of the cabinet white would reflect just as much light as would a shiny metal backer panel... still not enough to eliminate hot spots.

what about white plexi faces with dual-whitetrans.print layers?

 

[Marlene]

you could also try an arcylic that is more opaque as the ones that come wiht those can be kind of milky looking. MDI makes some nice stuff good deal getting them cheap

 

[Gino]

Trying to figure out what many of you are saying here with diffusing the opaqueness with vinyl or different kinds of substrate....... doesn't it stand to reason, if you decrease the light coming through at the hot spots with your substrate, it's gonna be even less at the other areas, resulting in the exact same problem, just not as bright all around ??

The lamps either need be moved back or the face outward. Otherwise, that neat new idea of aluminum tape will stop the glaring of the lamps and with the right amount on there should indeed solve your problem. Really, if you are looking at something and the sun is in your eyes, don't you shield the sun out of your eyes with your hand, so you can see more clearly ??
Don't people put lampshades on lamps so they don't have glaring lights in their eyes ??
Ever look at the bulbs in many of the headlights made today for automobiles. It's a rear reflected bulb off the background and the front is totally shielded from view.

I like that new idea. Wish I had thunk of it.............
​

 

[Moze]

Trying to figure out what many of you are saying here with diffusing the opaqueness with vinyl or different kinds of substrate....... doesn't it stand to reason, if you decrease the light coming through at the hot spots with your substrate, it's gonna be even less at the other areas, resulting in the exact same problem, just not as bright all around ??

The lamps either need be moved back or the face outward. Otherwise, that neat new idea of aluminum tape will stop the glaring of the lamps and with the right amount on there should indeed solve your problem. Really, if you are looking at something and the sun is in your eyes, don't you shield the sun out of your eyes with your hand, so you can see more clearly ??
Don't people put lampshades on lamps so they don't have glaring lights in their eyes ??
Ever look at the bulbs in many of the headlights made today for automobiles. It's a rear reflected bulb off the background and the front is totally shielded from view.

I like that new idea. Wish I had thunk of it.............
​

The diffuser acts to diffuse the light from the lamps. It spreads it out, it doesn't decrease it (if it does, it's very minimal).


Like Gino mentioned, the lamps are too close to the face and nothing you do (other than using a formed face) is going to eliminate hot spots (or shadowing from inserting materials in an attempt to eliminate the hot spots). Retrofit the cabinet with LED's, keep them pretty close together and apply a layer of vinyl diffuser to the back of the face (it's specifically meant for that purpose). Remove the back face and insert anything with a bright white surface - aluminum, ACM, etc.

 

[Pixels Are Bad Mmmkay?]

The diffuser acts to diffuse the light from the lamps. It spreads it out, it doesn't decrease it (if it does, it's very minimal).


Like Gino mentioned, the lamps are too close to the face and nothing you do (other than using a formed face) is going to eliminate hot spots (or shadowing from inserting materials in an attempt to eliminate the hot spots). Retrofit the cabinet with LED's, keep them pretty close together and apply a layer of vinyl diffuser to the back of the face (it's specifically meant for that purpose). Remove the back face and insert anything with a bright white surface - aluminum, ACM, etc.

If the face is 3 to 3.5 inches from the LED modules what would be an ideal spacing? Every 3-4 inches?