Behind-TV Lighting

[FreshDTSht]

Hey guys,

I'm hoping you can refresh my memory a bit. In the past there's been discussion on how to light your room so that you can watch movies in the dark without straining your eyes too much.
One of the solutions that I strongly recall hearing was that a light source behind the screen is helpful when watching in a dark room, as it allows your eyes a consistent light intensity which lowers strain. This is similar to those Philips Ambi-light televisions that were around a couple of years ago.

I went ahead and tried this concept out on my DLP tv with some small LED light pucks from Ikea. So far I'm pretty happy with it, and it does seem to help with my eyes after watching some movies in the dark.

Am I out of my mind here, or is this a point of discussion in the past we've had? I'll take some pics when I can and post them so you can see how it came out...

 

[PaulyT]

Yeah, that's come up before. I also have a lamp that's behind the plane of the screen that I put on low at night when using the TV (moves or games). It helps, esp. if you need to look at something other than the TV, get up and move around, etc.

 

[yromj]

Let me start by saying that if you like the effect of the light behind the screen, then awesome.

BUT, a light behind the TV (such as the "ambi-light") will really do nothing more than effectively diminish contrast, etc. While, yes, you should have some ambient light in the room, the source of that light should not be visible between the viewer and the screen.

A better option, IMHO, would be a dimmable light either overhead or somewhere else in the room farther back than the seating position.

John

 

[PaulyT]

Yeah, I have my lamp about 4' to the right and 1' above the TV - as far as I can get it in my small room. And it's a torch style, with the light facing up rather than shining towards me. It's not perfect, but anywhere else in the room and it just reflects off the screen which is much worse. I also hate lights behind me because they reflect off the rear surface of my glasses.

 

[Randy]

Let me start by saying that if you like the effect of the light behind the screen, then awesome.

BUT, a light behind the TV (such as the "ambi-light") will really do nothing more than effectively diminish contrast, etc. While, yes, you should have some ambient light in the room, the source of that light should not be visible between the viewer and the screen.

A better option, IMHO, would be a dimmable light either overhead or somewhere else in the room farther back than the seating position.

John

I like my light behind also, but with many displays you have to be careful to avoid glare. I think that is one of the many benefits of the "ambilight", that and the fact that those lights are supposed to 6500K lights so they help the eyes focus on the display a little better.

 

[Yesfan70]

I have a single canister light in the ceiling that I replaced the ceiling fan with when I hung my projector. I don't like it on for the same reasons that have been mentioned in this thread. It washes out the image a bit. Glare isn't much of an issue since I have a projo screen.

I thought about redoing my frame to where I can mount a couple of those "lit kits" (they are just fluorescent lights with some sort of filter on them, so they are at 6500K) in between the screen and the wall. Maybe do one on each side or just a single one at the bottom of the screen pointing to the floor behind my gear rack. I don't know yet to be honest.


Fresh,

There was a discussion on S&V about those, so no you're not out of your mind. Matter of fact, I'm pretty sure there was a topic on the AVS forums about making your own. It involved buying a fluorescent light kit (sort of the cheap style you would use in a small bathroom) and adding some sort of tint to the bulb or lens cover to get the color temperature right. Do a search for "6500K light" or similar and see what you get. I think even IG (Flint here) runs something on his RPTV.

 

[FreshDTSht]

Here is a couple of attempts at photos with the room darkened:
This picture is more to the side, so it looks a bit brighter than what it really is...

This is another not so good photo from the front. The light is not very bright, just enough to provide some illumination behind the tv.

Here's a photo of the little LED 'pucks' on the back of the TV. It actually came with 4, I've only used 2 so not to overdo it.

 

[DIYer]

One of the solutions that I strongly recall hearing was that a light source behind the screen is helpful when watching in a dark room, as it allows your eyes a consistent light intensity which lowers strain.

I've read about it before and from my recollection, it applies to smaller TV like the ones we used to have before the big screens became the norm. The theory about not needing it for big screen is that it's large enough (if size and distance are properly chosen) to fill the sufficient area of your cone of vision so that the contrast strain is not much of an issue. I watch movies with the room as dark as I can make ever since I bought BR player and preamp with back lit remote.

 

[Flint]

It is called "Bias Lighting" and it is absolutely necessary if you want to perceive color and contrast at the highest accuracy from a well calibrated display.

Basically, if you look at a TV screen and can see a black or extremely dark frame around it from an unlighted wall behind it, then you will not get the highest realism. Adding a proper bias light with color temp of 6,500K and a perfect 70% gray wall behind the TV, the color will be most ideal and the contrast will be perfect. Without that, your braind will not see things properly.

 

[DIYer]

Why don't they do this in movie theaters?

 

[Flint]

They do, but it isn't as obvious since the screen is so large. Ina movie theater the screen occupies the majority of your field of vision and this there is lighting on the side walls to prevent your peripheral vision from seeing pure black.

If your HT TV screen fills nearly all of your field of vision, then I guess it isn't as important to have a bias light. But you still do not want a pitch black room while watching TV.

For people with normal sized flat screen TVs or who sit farther away from large projection screens, the bias lighting is pretty important.

 

[Orbison]

It is called "Bias Lighting" and it is absolutely necessary if you want to perceive color and contrast at the highest accuracy from a well calibrated display.

Basically, if you look at a TV screen and can see a black or extremely dark frame around it from an unlighted wall behind it, then you will not get the highest realism. Adding a proper bias light with color temp of 6,500K and a perfect 70% gray wall behind the TV, the color will be most ideal and the contrast will be perfect. Without that, your braind will not see things properly.

What kind of light would this be if I want to get one? Is it just a particular type of bulb?

 

[Flint]

Most people use a flourescent tube designed to provide 6,500K temperature. They sell at most home DIY stores, like Lowe's or Home Depot.

 

[Towen7]

If your HT TV screen fills nearly all of your field of vision, then I guess it isn't as important to have a bias light. But you still do not want a pitch black room while watching TV.

I stole this picture from the internet to demonstrate one way to get "bias" lighting in with a big screen. I've never enjoyed watching TV with the lights off but thats a problem with a projector based display. So... I'm looking into adding a couple of sconces to either side of the screen like in the picture.

 

[yromj]

OK, so I stand corrected on my first post. (And, FWIW, the screenshots Freshie posted do look very good.)

I don't think I would like point sources of light on the side of the screen (ala T7's pic), though. I was really happy with the lighting in my room using the dimmable sconces on the side walls (preferred) or the in-ceiling can lights. My screen filled the majority of my vision, though.

John

 

[Towen7]

I don't think I would like point sources of light on the side of the screen (ala T7's pic), though. I was really happy with the lighting in my room using the dimmable sconces on the side walls (preferred) or the in-ceiling can lights. My screen filled the majority of my vision, though.

I'd also prefer to mount sconces on the side walls but there is no way to run wiring in the wall on the right side of the room. But now that I think of it I do have can lights in each corner... :eusa-think:

 

[yromj]

I'd also prefer to mount sconces on the side walls but there is no way to run wiring in the wall on the right side of the room. But now that I think of it I do have can lights in each corner... :eusa-think:

I think dimmed flood lights in the corners would be preferable to the sconces.

John

 

[Flint]

http://www.cinemaquestinc.com/ideal_lume.htm

A little light reading on why Bias lighting is critical.

 

[Yesfan70]

I'd also prefer to mount sconces on the side walls but there is no way to run wiring in the wall on the right side of the room. But now that I think of it I do have can lights in each corner... :eusa-think:

I think dimmed flood lights in the corners would be preferable to the sconces.

John

That's what I have. I actually thought about some art decco style sconces myself.

 

[yromj]

http://www.cinemaquestinc.com/ideal_lume.htm

A little light reading on why Bias lighting is critical.

:laughing-rolling: Oh jees you kill me. I'll bet that article is very illuminating though.

John