Originally Posted by is250sp
I've been doing research and keep reading conflicting information about contrast on DLP vs 3LCD projectors. Which technology has deeper blacks?
You have been given all truthful and accurate information about blacks and CR.
What I believe misleads people the most is not understanding how humans and their eyes perceive black. Measurements are great and they tell us a lot and the manufactures don’t help the things by stating a lot of highly over rated specs that don’t mean much in the real world but help them sell projectors.
The real bottom line IMO is in how we watch and how we perceive blacks though because our eyes are not light meters and actually if they were light meters they would be awful ones. Our eye has an iris that that opens and closes and adjusts how much light gets in. Our screens are white or gray and projectors don’t put out black light as a color to do black they just send out no light, so the black on the screen is how our eyes perceive it given how much light is in the room (ambient) and how bright the image is overall setting the size of our iris. A small iris / bright image will produce a on screen black that is very dark and convincing it is an inky black even though a meter will tell you it is a poor CR black. This is because our eyes take in the full image and adjust to average it and when the amount of black is overcome with brightness someplace else in the image the smaller iris lets in less light from what is black and thus it looks black. This is what people are talking about when they say perceived CR or perceived black. It is also the reason people say more lumens help with poor room or if you hear someone say I want to watch football in the daytime with some light coming in so I have a very bright projector. More lumens can’t make actual darker blacks as blacks are no lumens. What they do is make a brighter image and increase the perception of black. Dark gray screens help in a similar way.
Actual blacks occur when our iris is fully opened by a very dark image and perception is mostly not there. A good example is when the credits run at the end of the movie and there is mostly black on the screen or when the movie does a fade to black and we finally get to see the true black the projector is producing. This is why all the questions about room colors and ambient light. Because the very best projector that can produce the best black by stopping the most light will be easily destroyed by the slightest ambient light leakage.
This is why you seem to see a lot of discrepancy between reviews and specs with 4k DLP and 3LCD and older 1080p DLPs etc. When a projector is reviewed and measured and real numbers are assigned to CR, remember CR is the difference between black and white brightness. So if a projector puts out 1 lumen doing black and 2000 lumens doing white it is said to have 2000:1 CR. Then you will read another review that is done visually and they will say the picture is so spectacular and colors are vivid and lifelike and blacks dark and convincing. They are not lying it is what they see.
Many times for most people the only times they will be bothered by a lesser CR is in a dark nighttime image and most of the time those problems are largely and mostly ambient light in the room.
Directors of movies know this and know their movies will be playing in commercial theaters that get pretty dark but are far from perfect so even in the dark nighttime images they use some lighting during filming to help with a little perception happening.
It is really mostly about how much of that type of image you watch and how important it is that you get blacks at those times as dark as don’t bother you and your room will support.
Some people are very obsessed with these black levels others not so much. I personally just understand and except the limitation of projection in these areas and the advantages more than outweigh the disadvantages. Just know the difference in these CR isn’t going to be that apparent in 99% of what most of us watch.
That’s my opinion others may not agree.