Which of the following is accurate regarding facial and shoulder lighting measurements in a TelePresence
environment?
A.
Facial lighting should be from 200 to 400 lux by using direct lighting and with the endpoint on.
B.
Facial lighting should be from 200 to 400 lux by using indirect lighting and with the endpoint off.
C.
Shoulder lighting should be from 200 to 400 lux by using direct lighting and with the endpoint on.
D.
Shoulder lighting should be from 200 to 400 lux by using indirect lighting and with the endpoint off.
E.
Room lighting should be from 200 to 400 lux by using direct lighting and with the endpoint on.
F.
Room lighting should be from 200 to 400 lux by using indirect lighting and with the endpoint off.
Explanation:
In a Cisco TelePresence environment, facial lighting should be from 200 to 400 lux by using indirect lighting and
with the endpoint off. Facial lighting is measured by holding a light meter at the person’s face and pointing it
toward the camera; this is called vertical plane lighting. Shoulder lighting is measured by pointing the light meter
at the ceiling; this is called horizontal plane lighting. Shoulder lighting should not exceed two times the value of
the facial lighting. Facial and shoulder lighting measurements should always be taken with the Cisco
TelePresence endpoint off. The integrated lighting of the Cisco TelePresence endpoint will provide
approximately 100 lux.
Lux is a measurement of the intensity of a light that strikes a surface. If you do not have a lux meter, you can
calculate lux by using the following formula:
lux = (lumens / meters2)
Lumens is a measurement of the amount of light that is emitted from a light source. A wall that is 5 meters
away from a 4000lumen light source would have a lux value of 160:
lux = (4000 / 52) = (4000 / 25) = 160
Room lighting should be equal to or less than the facial lighting and should not vary more than 100 lux within
the room. A dimming lighting control system should be used to provide consistent lighting throughout the
environment. Because direct lighting can cause shadowing and glare, Cisco recommends that indirect lighting
be used in Cisco TelePresence environments.Cisco: Cisco TelePresence Room Design Guide: Indirect Lighting (PDF)