Question on lighting and eye strain

Setup:
-Sharp Aquos 32inch
-Room lit with 3x 30W 3000K compact fluorescent (100 watt equiv to a regular
bulb) lamps.
-The room is lit about 80% of normal daylight
-Small fluorescent tube behind the TV to do bias lighting (8+12watts (equiv
of about a 60watt bulb) -- 3000K I think)
-TV is in a cabinet so the bias light fills the cabinet

When I used to have a basic CRT TV and just a basic 160Watt overhead regular
bulb fixture and no bias lighting I could watch TV for many hours -- but now
with this setup my eyes get tired too easily (2-3 hours movie makes them
very tired).

Is it OK to just have a basic fluorescent tube to act as a bias light? could
TV bright/contrast be a factor (I use the factory setting for medium color
temp and standard viewing)? What is the proper amount of light in a room for
TV (I currently have 70-80% daylight.

Any ideas would be appreciated -- I am happy to change the lighting in the
room but I don't know what would make sense as far as how much light, etc.

Thanks!

"mBird" wrote in message
...
Setup:
-Sharp Aquos 32inch
-Room lit with 3x 30W 3000K compact fluorescent (100 watt equiv to a
regular bulb) lamps.
-The room is lit about 80% of normal daylight
-Small fluorescent tube behind the TV to do bias lighting (8+12watts
(equiv of about a 60watt bulb) -- 3000K I think)
-TV is in a cabinet so the bias light fills the cabinet

When I used to have a basic CRT TV and just a basic 160Watt overhead
regular bulb fixture and no bias lighting I could watch TV for many
hours -- but now with this setup my eyes get tired too easily (2-3 hours
movie makes them very tired).

Is it OK to just have a basic fluorescent tube to act as a bias light?
could TV bright/contrast be a factor (I use the factory setting for medium
color temp and standard viewing)? What is the proper amount of light in a
room for TV (I currently have 70-80% daylight.

Any ideas would be appreciated -- I am happy to change the lighting in the
room but I don't know what would make sense as far as how much light, etc.

Thanks!

Some good reading on the subject he
http://www.cinemaquestinc.com/ideal_lume.htm
Bob

In article "mBird" writes:
Setup:
-Sharp Aquos 32inch
-Room lit with 3x 30W 3000K compact fluorescent (100 watt equiv to a regular
bulb) lamps.
-The room is lit about 80% of normal daylight
-Small fluorescent tube behind the TV to do bias lighting (8+12watts (equiv
of about a 60watt bulb) -- 3000K I think)
-TV is in a cabinet so the bias light fills the cabinet

When I used to have a basic CRT TV and just a basic 160Watt overhead regular
bulb fixture and no bias lighting I could watch TV for many hours -- but now
with this setup my eyes get tired too easily (2-3 hours movie makes them
very tired).

Is it OK to just have a basic fluorescent tube to act as a bias light? could
TV bright/contrast be a factor (I use the factory setting for medium color
temp and standard viewing)? What is the proper amount of light in a room for
TV (I currently have 70-80% daylight.

Any ideas would be appreciated -- I am happy to change the lighting in the
room but I don't know what would make sense as far as how much light, etc.

Thanks!


I don't know how you are getting 80 percent of daylight levels (which
would be about 500-600 watts watts per square meter) out of 3x30 watt CF
lights.

It was my understanding that the light in the room was also supposed to be
6500K and the walls were to be a neutral color.

I think the amount of light used depends on the size of the room, the locations
of the light, and the lightness of the room. Being compatable with the brightness
of the screen is also important, as one doesn't want the screen to be a bright
spot in a dark room, for example.


Alan

On Feb 28, 2:56 am, (Alan) wrote:
snip
I don't know how you are getting 80 percent of daylight levels
(which
would be about 500-600 watts watts per square meter) out of 3x30
watt CF
lights.

It was my understanding that the light in the room was also
supposed to be
6500K and the walls were to be a neutral color.

I think the amount of light used depends on the size of the room,
the locations
of the light, and the lightness of the room. Being compatable with
the brightness
of the screen is also important, as one doesn't want the screen to
be a bright
spot in a dark room, for example.

Alan

The telecine suites I worked at in Hollywood (maintenance engineer,
not colorist) used 5000K dimmable flourescents with neutral gray
fabric covered walls. The monitors were Sony BVM-1910 calibrated to
6500K and 30 foot-lamberts on white (100 IRE). 20 IRE was around .5 fL
with the final setting for the black pluge. The CRTs are not all the
same. The monitors were verified by the THX folks periodically. Ours
always passed BTW.

The ambient light level was far lower than you folks are talking
about. A mini Mag-Lite set to widest field from around 8 feet would be
pretty close to the ambient level the colorists used.

At the time ('94-'97) we were transferring 'A' titles for Universal in
5 bays. Any major Universal movies you rented then came through my
telecines - Rank Turbo 1 and Turbo 2 with DAV digital deflection, DAV
Accu-glow and DAV Accu-Grade, the latter 2 additions designed by me.

GG

On Feb 27, 6:24 am, "mBird" wrote:
Setup:
-Sharp Aquos 32inch
-Room lit with 3x 30W 3000K compact fluorescent (100 watt equiv to a regular
bulb) lamps.
-The room is lit about 80% of normal daylight
-Small fluorescent tube behind the TV to do biaslighting(8+12watts (equiv
of about a 60watt bulb) -- 3000K I think)
-TV is in a cabinet so the biaslightfills the cabinet

When I used to have a basic CRT TV and just a basic 160Watt overhead regular
bulb fixture and no biaslightingI could watch TV for many hours -- but now
with this setup my eyes get tired too easily (2-3 hours movie makes them
very tired).

Is it OK to just have a basic fluorescent tube to act as a biaslight? could
TV bright/contrast be a factor (I use the factory setting for medium color
temp and standard viewing)? What is the proper amount oflightin a room for
TV (I currently have 70-80% daylight.

Any ideas would be appreciated -- I am happy to change thelightingin the
room but I don't know what would make sense as far as how muchlight, etc.

Thanks!

Chances are good that you have too much light!
Chances are also good that the screw-iin fluorescents you are using
are creating glare. If they don't fit the fixture well, and especially
if you can see the lamp directly then they are likely the cause.

Try using just the bias light.

Richard Reid, LC

Flourescent light flickers at 60 hz. tv flickers at 59. and change hz. this
produces a beat that your eye may or may not see. your brain DOES see this
beat and this is what is causing you pain. Replace all the flourescent
lighting that can strike the tv screen and your eyestrain will go
away."mBird" wrote in message
...
Setup:
-Sharp Aquos 32inch
-Room lit with 3x 30W 3000K compact fluorescent (100 watt equiv to a
regular bulb) lamps.
-The room is lit about 80% of normal daylight
-Small fluorescent tube behind the TV to do bias lighting (8+12watts
(equiv of about a 60watt bulb) -- 3000K I think)
-TV is in a cabinet so the bias light fills the cabinet

When I used to have a basic CRT TV and just a basic 160Watt overhead
regular bulb fixture and no bias lighting I could watch TV for many
hours -- but now with this setup my eyes get tired too easily (2-3 hours
movie makes them very tired).

Is it OK to just have a basic fluorescent tube to act as a bias light?
could TV bright/contrast be a factor (I use the factory setting for medium
color temp and standard viewing)? What is the proper amount of light in a
room for TV (I currently have 70-80% daylight.

Any ideas would be appreciated -- I am happy to change the lighting in the
room but I don't know what would make sense as far as how much light, etc.

Thanks!

On Apr 15, 1:33 pm, "Larry" wrote:
Flourescent light flickers at 60 hz. tv flickers at 59. and change hz. this
produces a beat that your eye may or may not see. your brain DOES see this
beat and this is what is causing you pain. Replace all the flourescent
lighting that can strike the tv screen and your eyestrain will goaway."mBird" wrote in message

...

Setup:
-Sharp Aquos 32inch
-Room lit with 3x 30W 3000K compact fluorescent (100 watt equiv to a
regular bulb) lamps.
-The room is lit about 80% of normal daylight
-Small fluorescent tube behind the TV to do bias lighting (8+12watts
(equiv of about a 60watt bulb) -- 3000K I think)
-TV is in a cabinet so the bias light fills the cabinet

When I used to have a basic CRT TV and just a basic 160Watt overhead
regular bulb fixture and no bias lighting I could watch TV for many
hours -- but now with this setup my eyes get tired too easily (2-3 hours
movie makes them very tired).

Is it OK to just have a basic fluorescent tube to act as a bias light?
could TV bright/contrast be a factor (I use the factory setting for medium
color temp and standard viewing)? What is the proper amount of light in a
room for TV (I currently have 70-80% daylight.

Any ideas would be appreciated -- I am happy to change the lighting in the
room but I don't know what would make sense as far as how much light, etc.

Thanks!

I replaced my kitchen fluorescent task rod lighting under the
cabinets with Xenon. It is a soft pleasant light but not cool. I can
feel the warmth of the gas sometimes when I bend over the sink. The
fluorescents made me nauseous and gave me headaches.

Diva

Diva

In article et "Larry" writes:
Flourescent light flickers at 60 hz.

Many flourescent lights flickers at 120 Hz (in the 60 Hz power world).
Once for each half cycle of the power line. A few flicker at a few thousand
hertz (with solid state power supplies).

tv flickers at 59. and change hz.

TV flickers at 59.97 Hz, sort of.

LCD doesn't flicker at all. DLP flickers at much higher rates.


this
produces a beat that your eye may or may not see.

A beat only is produced when you have a nonlinear mixing or switching of the
signals. For example, a camera with no memory (such as a high speed shutter,
or ancient iconoscope or image dissector camera tube), and a flickering light
source. To deal with that, some folks ran studio lights off of DC.

Two light sources at differing frequencies in the same room do not cause a beat.

your brain DOES see this
beat and this is what is causing you pain. Replace all the flourescent
lighting that can strike the tv screen and your eyestrain will go
away.

The light reflecting off the TV screen may be causing eyestrain, but it
has nothing to do with a beat effect.

Alan

In article ,
(Alan) wrote:

In article et "Larry"
writes:
Flourescent light flickers at 60 hz.

Many flourescent lights flickers at 120 Hz (in the 60 Hz power world).
Once for each half cycle of the power line. A few flicker at a few thousand
hertz (with solid state power supplies).

tv flickers at 59. and change hz.

TV flickers at 59.97 Hz, sort of.

Actually 50.94, twice 29.97 which is the frame rate.

LCD doesn't flicker at all. DLP flickers at much higher rates.


this produces a beat that your eye may or may not see.

A beat only is produced when you have a nonlinear mixing or switching
of the signals. For example, a camera with no memory (such as a high
speed shutter, or ancient iconoscope or image dissector camera tube),
and a flickering light source. To deal with that, some folks ran
studio lights off of DC.

Two light sources at differing frequencies in the same room do not
cause a beat.

your brain DOES see this beat and this is what is causing you pain.
Replace all the flourescent lighting that can strike the tv screen
and your eyestrain will go away.

The light reflecting off the TV screen may be causing eyestrain, but
it has nothing to do with a beat effect.

Alan

--
Tom Stiller

PGP fingerprint = 5108 DDB2 9761 EDE5 E7E3
7BDA 71ED 6496 99C0 C7CF

In article ,
Tom Stiller wrote:

In article ,
(Alan) wrote:

In article et "Larry"
writes:
Flourescent light flickers at 60 hz.

Many flourescent lights flickers at 120 Hz (in the 60 Hz power world).
Once for each half cycle of the power line. A few flicker at a few thousand
hertz (with solid state power supplies).

tv flickers at 59. and change hz.

TV flickers at 59.97 Hz, sort of.

Actually 50.94, twice 29.97 which is the frame rate.
Oops that should be 59.94.
^

LCD doesn't flicker at all. DLP flickers at much higher rates.


this produces a beat that your eye may or may not see.

A beat only is produced when you have a nonlinear mixing or switching
of the signals. For example, a camera with no memory (such as a high
speed shutter, or ancient iconoscope or image dissector camera tube),
and a flickering light source. To deal with that, some folks ran
studio lights off of DC.

Two light sources at differing frequencies in the same room do not
cause a beat.

your brain DOES see this beat and this is what is causing you pain.
Replace all the flourescent lighting that can strike the tv screen
and your eyestrain will go away.

The light reflecting off the TV screen may be causing eyestrain, but
it has nothing to do with a beat effect.

Alan

--
Tom Stiller

PGP fingerprint = 5108 DDB2 9761 EDE5 E7E3
7BDA 71ED 6496 99C0 C7CF