Blacks is black and white is white

A photo or video image is made up of all shades of gray from black to white and all the colors that go along with them. The goal is for the whites to be white and the blacks to be black with everything in the middle to be in the right place along the scale.

There are two general ways to do this. One is to start with a white surface such as white paper or canvas and build up pigment or ink to get to black. With good paper and high quality printers or paint, this works great. The opposite approach is to start with a black surface such as a TV or computer monitor and light it up to produce white. This also works very well. In each case how black the screen or how white the paper are big factors in the quality of the image.

A nearly impossible task is start with a white surface and try to light it to produce a whole range of tones from black to white. This is theoretically impossible and practically very difficult. Movie theaters are able to do this for all practical purposes by darkening the room so that the white screen looks black and then lighting it with the projector. Sometimes a silver screen could be used which is easier to make look black and is more reflective for the white areas, but reflective screens have their own problems such as stray reflections and directionality.

For this reason the use of video projectors in lighted rooms cannot produce images with an acceptable degree of tonal range no matter how powerful the projector.

I foresee that video projectors such as currently used will soon go the way of broadcast TV and wired telephones. LCD flat screen video monitors are a much better choice in most situations. The breakthrough that is needed is folding LCD screens. I presume that engineers are already working on this. Stay tuned.