Home Theater Forum and Systems - HomeTheaterShack.com (https://www.hometheatershack.com/forums/)
-   General Screen Discussion (https://www.hometheatershack.com/forums/general-screen-discussion/)
-   -   Ambient light measurement standards (https://www.hometheatershack.com/forums/general-screen-discussion/120033-ambient-light-measurement-standards.html)

 A J 04-20-15 01:07 PM

Ambient light measurement standards

All,

I measured the light hitting my potential screen position with my windows open (measured in direction of proposed projector position) and get a consistent 5 lux.

5 lux = .46 footcandles
5 lux = .47 footlamberts

My proposed usage is an Epson 3050 from 11.5ft onto 100" diagonal.

Using the Projector Central calculator and a 1.0 gain screen shows an image brightness of 30 foot lamberts.

If ambient light occurs from the side, shouldn't the vast majority of the light just 'skip' off (angle of incidence = angle of reflection ...) ?

I always try to over analyze things and really need to fully understand ambient light and measurements.

What measurements etc. can I take to better quantify my living room as a projector/screen location?

AJ

 Yiannis1970 04-20-15 05:53 PM

Re: Ambient light measurement standards

If you have already measured the incident light (5 lux), job is done!:)

 A J 04-20-15 06:01 PM

Re: Ambient light measurement standards

Quote:
 Yiannis1970 wrote: (Post 1180729) If you have already measured the incident light (5 lux), job is done!:)

Great, just curious if that is the right approach (aiming from screen location toward projector to) or should I aim at the windows each direction to measure the light?

Thanks,
AJ

 Yiannis1970 04-21-15 02:24 AM

Re: Ambient light measurement standards

Although i believe would make the slightest difference because the light is being reflected from wall to wall into your room, let's say the proper way to do it is to aim your luxometer directly against the primary source of light. In other words, from the screen position you can aim directly your windows.

 All times are GMT -5. The time now is 02:02 AM.

Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.

Copyright ©2006 - 2019, Home Theater Shack, LLC.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.

For the best viewing experience please update your browser to Google Chrome