Just curious. Some reviews report a projector's lowest light output in fL, with some of the better units coming in at .001-.003 footlamberts. How do these levels compare to the lowest black level I might see at my local cineplex?

Thanks,

Warren

Digital cinema is specified for 2000:1 ON/OFF contrast and 14ftL peak whites, 12ftL reference whites. Your local cineplex complying with that is unlikely....

ftL used as a measure in reviews is useless if they don't tell you what the white measure was. Anyone can setup a screen too dim or too brite for the PJ. Some do it under the guise of "comparison" reviews - but the winner will be the PJ that was matched to the screen. It is unrealistic that someone would over/underdrive a screen in a calibrated setup. Pay attention to calibrated contrast numbers - divide by your ftL target - that is your blacks.

Thank you. The reviews that I mentioned usually do report peak white level along with the black level, after the display had been calibrated to their standard. So for digital cinema with peak white at 14 fL and 2000:1 CR, would that translate to a black level of 0.007 fL?

Warren

As already mentioned, digital cinema projectors have a typical on/off CR of about 2000:1. The first reason why this is not higher is because of the importance of light output...even more important than it is for home theater. The second reason is because of rapidly diminishing benefit caused by the ambient light, anticipated by the DCI specs to be as high as .01fL from the screen. A projector with 2000:1 CR in an environment with .01fL ambient and 14fL white will produce .017fL black and CR of 824:1.

Thank you very much!

Warren