what am i doing wrong?

[Anonymous]

i was calibrating a projector today and setting the actual brightness (foot lamberts measurement of a 100% white window with 25% APL) or in chromapure the “small windows” setting.

My memory and my spreadsheet tell me that i should be aiming for about 14 fL for a projector. The lowest i could get it was about 27 fL. so i finished the calibration and tested with some Blu-rays.

The colours were good but the picture was horrendously dull so much so that i had to increase it to about 42 fL to look right.

i also did a TV recently and set it to 30 fL through the backlight and the same thing – it wasnt bright enough.

Am i taking the wrong measurement… is my memory incorrect? i feel im doing something obviously wrong.

ive attached a screenshot of my 42fL measurement.

Thanks for any help.

Topic

[Anonymous]

Hello,
I am guessing that you may be reading Luminance in Candela/Meter^2 not Foot-lambert.
Check the settings on your software to change output reading.

Hope this helps

RayJr

[Anonymous]

unfortunately not – i make sure every time its fL and not cd/m2

[Anonymous]

i just checked chromapure and in the main page settings luminance was set to candelas and the settings for white balance was set to foot lamberts.. so i guess you were right.

[Anonymous]

Glad you were able to get it figured out.

RayJr

[Author]

Replies