Tips for Improving Your Home Theatre Viewing Experience
Backlighting the Display & Ambient Light
Have you ever watched TV late at night with all the lights out in complete darkness? After a time, did you experience eye strain or discomfort. Well, you arent alone. We will address this issue and provide some tips & tricks on how to improve your viewing experience with incidental lighting in this report.
Why did you experience eye strain and discomfort, perhaps headaches, with the lights out? The reason is that the sole light source, your display or TV set is an ever shifting level of light as the images roll across the screen, sometimes rather dark and other times bright. With this changing light, you pupils dilate and contract. But that isn't all, the complete darkness (besides the TV) means that your pupil is dilated on average to a much larger diameter. What does that have to do with anything? Have you ever looked through a keyhole or a peephole? Did you notice that everything seemed to be in focus from up close to far away? This optical property is in play with your pupils. When dilated wide open, the depth of field of objects in focus is much diminished, but when the pupil is very small, like in full daylight or in a lighted room, objects near and far are both in focus. In that dark room with the TV, your dilated pupils, have minimal depth of field, and are continuously searching for focus. The way to address this is to shut down the pupil with some incidental lighting, or even better, backlighting!
There are some terms that lighting experts use to describe the characteristics of light.
Lumen rating describes the total intensity of the light being output. We want enough light to shut down the pupil some and gain depth of field, without overpowering the TV displays light output. That 100 watt classic incandescent is too much, ouch! A 60 watt incandescent in a table lamp is much better, 40 watt even better. For backlighting the TV set itself though, 25 watt incandescent is more like it. This figure is used more often these days, but in the past, when incandescent lights were the most commonly available bulbs for the home, wattage became a common alternative to lumen rating. However with new light fixture technology, light halogen, florescent, led and others, you cant use wattage to determine the relative lumens between the units. Lumen ratings can be used across technologies to compare light output. Check some common wattages for standard incandescent bulbs for their lumen rating and then use that to gauge other light technologies output.
CRI, or Color Rendering Index, is another aspect of the light that interests us. Different light technologies produce light that is not uniform across the visible light spectrum. This alters the colors of objects that you see illuminated by them. For color fidelity, choose a light bulb with a high CRI, in the 90s (on a scale of 100).
Temperature is yet another aspect of light that is of interest to us. You've no doubt seen cool lighting of classic standard flourescents and warm lighting of halogens. Now flourescents and other lighting technologies come in a variety of temperature ratings. You can get flourescents with 2700K (very warm) 3500K, 4100K, 5000K, and 6500K ratings. 6500K is the temperature standard that film and television production use for color rendering. Your TV sets colors are set to this standard. A correctly calibrated TV set's white will match the white of the 6500K bulbs. So this is a neutral light for color rendering, aka the standard!
What is available?
CinemaQuest Ideal - Lume
CinemaQuest offers the Ideal-Lume. A 98 CRI 6500K florescent tube light in a housing specifically designed for backlighting displays. Check out the particulars on the link. CinemaQuest's website also has fantastic information on 6500K, CRI, and other technical issues on backlighting displays. An outstanding product!
That's expensive, anything cheaper?
All of the big manufacturers make 6500k florescent tubes in a variety of standard sizes and can be found at local Home Depot's and Lowe's and even Walmarts and other retailers. All of these are very good alternatives to the above. Compare the CRI's before purchasing. You can also find 6500K Available in CFL, Compact Florescent as well. All of these manufacturers also make a 5000k Sunlight model.
Daylight Florescent Tubes 6500K
Philips Daylight Deluxe
GE Daylight Deluxe
What to put them in?
Walmart has a half dozen Under Cabinet Lighting & Utitlity Lights, which come in a variety of sizes from 6" to 12" and use a variety of standard sized flourescent tubing, and standard wall plugs. Great for mounting behind the Flat Panel TV with double sided tape or clear packing tape. Perfect! Other retailers are sure to have them, or you can Google "under cabinet lighting" or "utitility lighting." If the light is too bright for your liking, you can use aluminum foil wrapped around the fixture to cut down the light to the desired level, leaving some portion of the middle of the bulb exposed.
Other Backlighting Considerations
Backlighting works best when the Flat Panel TV is on a TV stand a bit from the wall, parallel to the wall. Light gray paint is ideal, however other light neutral colors work great too, like beige, tan, or white. If you have hot yellow, dark blue, or deep red don't dispair, it will work well, its just not ideal.
My TV doesn't have a wall behind it or is in the corner, what to do?
If your TV is in corner, or not against a wall, then backlighting is not for you, but you can still get the benefits of incidental ambient lighting.
6500K or Wide Spectrum = Incandescents, Halogens, CFLs
- Replace the bulb in your table lamp.
These 2 series of incandescent bulbs are made to show accurate colors, with their wide evenly illuminated spectrums. Excellent for our purposes, and are widely available at major retailers. The GE Reveal line also has halogen and compact florescent bulbs available.
SoLux is a patented halogen light source designed to replicate natural sunlight and is used in many of the world's top museums including the Van Gogh and Guggenheim Museum is testament to its unmatched color quality. Many styles are available, from track lighting fixtures to clamp on fixtures. Professional and high quality, check the link for more information on models and usage.
Solux Art Light
Solux Track Light Single Head
Solux Wall Mount
Fish Tank Light
- Turn on the Fish Tank Light, Works Great! You can even replace the florescent tubes with 6500K high CRIs if you like! Come in all shapes and sizes. The water filtered light is really eye pleasing and tranquil.
LED Rope Lights
- Wrap around the backside of the Flat Panel TV, for backlighting.
IKEA White Dioder
- Just like the rope lights, perhaps smaller and better. Can be used with wall mounted Flat Panels. Also many generic brands available.
Christmas Tree Lights
- Use the small bulb white lights. The small 10 light string works great in a ficus tree. You dont have to decorate it with christmas ornaments though!
Halogen Mini Spot
- Uplight plants, or place behind the plants and uplight the wall/ceiling. You dont really want to see the direct light. You can even get these in GE Reveal Wide Spectrum halogens, but I like the warmer light of the standard halogen. The 25 watt halogen spots are plenty for our purposes here.
Electric Candle Lamp
- Just place this on a table somewhere. Comes in all kinds of styles. Real candles work too, but you will need more than one, generally, to get sufficient light.
Dimming Torchiere Lamp
- Adjust it down to a pleasing level. Throws up a nice backround light toward the wall and ceiling and away from your eyes. In general, this is what you are shooting for, you want indirect diffused light, bouncing off walls or filtered through water, lamp shades, etc.
Wait a second! What happened to 6500K and High Color Rendition Index?
I didnt get that one past you, did I? Well, since most of us dont have ideal situations, or dedicated Home Theatre Rooms, we make compromises in the interest of general living spaces and the areas we have to work with. The most important thing, is to get some steady incidental ambient light going, to keep your pupil shut down in a steady state. The above are some pleasing ways to do so. As for myself, I prefer a warmer light, and have eschewed the 6500K standard for my backlighting and incidental ambient lighting purposes.
One last comment about backlighting vs incidental ambient lighting...
Backlighting does offer an advantage over incidental lighting, in that it delineates the black bezel around the screen itself and highlights it. This heightens the already high contrast of black bezel to the screen and the wall, and gives it a 3 Dimensional effect, which is very pleasing. It's not a big deal, but worth mentioning.
Philips Ambilight LCD Flat Panel HDTVs
Philips released several series of TVs with backlighting integrated into the design, called Ambilight. They also integrated it into the TV signal, analyzing prominent colors on the television image and mimicking them with colored light and varying intensity. However I found this a bit busy and distracting. The additional colored light also distorts the color on screen as it activates the rods on your retina. You could choose steady white light or varying white light, in all models though. Check it out below...
You can get a similar effect using...
IKEA Multi-Color Dioder
Remember, do what you like, and what makes you comfortable, its your home and entertainment.
Next week we'll discuss unwanted ambient light, from windows and elsewhere, and how to control it.