I'm not sure how many people have heard about or actually use this so i figured i'd get a post up about it

D65 back or bias lighting actually improves the picture that you'll see on your TV & help prevent eye strain. The proof of the pudding is in the eating so they say. As i own a Philips TV with Ambilight i can have lots of pretty colours blown on to the wall behind the TV that is supposed (according to Philips) to enhance the viewing experience. These are or can be set to match colours that are produced around the screen edges. What it actually does is distort the colour that you view on the screen. I'll see if i can find something to demostrate this, i think you'll be pretty surprised, i know i was

Having discovered this & being lucky that i happen to have Ambilight spectra 3 i soon discovered that i could set the Ambilight to very close to the colour temperature 6500 Kelvin (6500K - D65) & lock it there. The difference this made to viewing was pretty astounding to say the least. No light need to be on in the room as the Ambilight supplies enough from behind the screen to do whatever you need to do. It also improves the contrast ratio

All that is needed to carry this out is some kind of 6500K source of light with a colour rendering index (CRI) of 90 or more. Something like a 15W triphosphor 6500K energy saver right hard up against the back of the TV itself should do the trick for a 42" TV Other tubes that could be used include older halophosphate tubes such as "Northlight" at about 20W due to it being less efficient.

What you are aiming for is about 10% of full screen white brightness as a maximum Smaller TVs will need less powerful tubes, larger TVs a bit more..

Here is a bit of bumph i just found just so you don't think Mark has lost the plot

What are the recommended elements of properly implemented bias lighting?

1. The color of light should be as close as possible to the video white point of 'CIE D65' (loosely referred to as 6500 Kelvins) for color video viewing ['D50,' the 'E' point, or ~5400K in other specific applications].
2. The color rendering index (CRI) is often published for a given lamp. A minimum CRI of 90 out of 100 is recommended for color reference applications.
3. The illumination should originate from behind the frontal plane of the screen to avoid reflections, haze, and glare (which interfere with, contaminate, and obscure the image).
4. The lamp itself should not be directly visible to the viewer, but rather the illumination should be reflected by surrounding surfaces, such as the wall behind the monitor.
5. The brightness of the reflected illumination should be 10% or less of the brightest white the monitor is adjusted to (calibrated for a dark environment).
6. Surrounding surfaces within the observer's field of view of the monitor screen should be neutral in color (gray to white), see: Munsell Color Order System's neutral value scale.
7. Completely surrounding the monitor screen with illumination is not necessary to realize the principle benefits of the technique.
8. It usually works best for the lamp to be mounted on the back of the monitor or TV cabinet (rather than on the wall), in order for the illumination to spread out over some distance.
9. Test patterns for adjusting bias lighting relative to the monitor screen are available in many optical disc programs for setting up home entertainment systems (see: 'Avia II- Guide to Home Theater,' 'Digital Video Essentials' series, etc.).

What are the proven benefits of correctly implemented bias lighting?

1. Reduces or eliminates eye strain and viewing fatigue in dark viewing conditions.
2. Eliminates image contamination due to reflections, haze and glare on the screen from conventional room lighting.
3. Enhances perceived black levels, contrast ratio, and picture detail by enabling dark adapted viewing.
4. Preserves correct color perception of the video image by the viewer.
5. Prolongs monitor phosphor life by enabling dark room viewing and lowering of screen brightness requirements (phosphors are used in CRTs, plasmas, and LCDs with CCF or white LED back lighting).
6. Provides a low level of illumination in the room for movement and peripheral activities.

Says who?

The following organizations are confirmed to define, recommend, specify, and/or use the technique of video bias lighting:

The Society of Motion Picture and Television Engineers (SMPTE)
The International Organization for Standardization (ISO)
The International Telecommunications Union (ITU)
The National Institute of Standards and Technology (NIST)
The Metropolitan Museum of Art
Industrial Light and Magic (ILM)
The Imaging Science Foundation (ISF)
THX, Ltd.
Electronic Arts (EA)
by deluxe
Microsoft Corporation
Image Entertainment
Universal Studios
PostWorks
Joe Kane Productions
Ovation Multimedia
DisplayMate Technologies
CNET Labs
Radical Games
Factor5 Studios
High Moon Studios
CinRam
Rev13 Films
Advanced Television Evaluation Lab- Communications Research Centre- Canada
Apple Corporation
Filet Post Production
Post and Beam
Cheyenne Mtn. Entertainment
Zombie Studios
CBS Television
Deluxe Digital Studios
Splice Here
Slant Six Games
New Hat LLC
Roush Media
Samsung Germany
Digital Film Lab- Denmark
Nice Shoes, VFX New York
Desperate Housewives, Editorial
Rockhopper Post
Live Nation Studios
LionAV Consultants
Avical
Technicolor-NY
Technicolor-Canada
Max Post
Bandito Brothers Studio
Chainsaw Edit
Twin Cities Public Television
Colorflow Post
ABC Television
The Moving Picture Company



Courtesy of this site here