Projection Environment Conditions

[BarkingGhost]

Do you plan on or have already bought a front projector, AND based strongly on the purchase decision the advertised Contrast Ratio performance?

Simple On/Off Contrast Ratio is a measurement of peak white output in full field without blooming, divided by the measurement of lowest black output in full field without crushing.

For instance, an example would be a hypothetical projector can display a full-field peak white that isn't blooming of 1000 lumens, and its uncrushed lowest black light output is 1 lumen. 1,000 / 1 equals a 1,000:1 Contrast Ratio.

Now, my concern is let's say another hypothetical projector claims 10,000:1 Contrast Ratio. Without knowing what the non-blooming peak white or uncrushed black value was, it would be hard to know how the projector is actually performing.

Business projectors typically are used in working environments with a lot of ambient lighting measuring well into the hundreds or thousands of lumens. As such, a business projector typically doesn't care about the uncrushed black light output of a projector and focuses on the non-blooming peak white output.

On the other hand, in a home theater environment the typical working environment is usually light-controlled. I light controlled environment can be quite strong in its ability to control, or even eliminate, all light not coming from the projector itself.

As a result, a typical home theater projector needs to advertise its Contrast Ratio performance in terms of how well it can control light output when it is not wanted. For instance, a fade to black scene in a movie scene that was pretty dark already may lead to a 'black field' that is really more dark gray then true black.

The display technologies currently in production in mass market are all based on blocking, or hiding, light output from their respective light sources. Old technology like Cathode Ray Tube, and future technologies like SED/FED simply do not generate light when it is not called for.

Now imagine, a business projector will an uncrushed black level output of, say, 100 lumens to that of a home theater projector at 0.1 lumen. But the threshold in which the viewer determines his or her desired acceptance of what 'black' is can vary, both in general, and from movie scene to movie scene.

It is not uncommon, though, for manufacturers to make rather outrageous claims in the performance of On/Off Contrast ratios. Why is it so easy to make these virtual-lie claims? Because, most folks do not have access to, nor financial resources to accommodate the necessary equipment to measure the lowest light output from a projector.

Another hypothetical projector may be marketed as having 30,000:1 Contrast Ratio, but a peak, non-blooming white output of 750 lumens. This would mean the marketing is suggesting a uncrushed black light output of 750 / 30,000, or 0.025 lumens. But if you or I didn't have a means to measure that little of light then there would be no way to call the manufacturer out on it.

Now some would say they couldn't tell the difference between 1 and 0.025 lumens, and that may be the case. I could also suggest I couldn't tell the difference between 0.025 and 0.000001. But if I claimed my 750 lumen non-blooming peak output project had a Contrast Ratio of 750 Million to 1 how much worth or value would you place on the aspect of the projector?

First, since I do not know of any measuring device that can measure 1/1,000,000 lumens. As such, I can feel comfortable knowing no consumer can prove that I am lying in my market of Contrast Ratio. I could claim whatever I want, and many manufacturers do, and no consumer protection is there waiting to protect you, or me.

So keep this in mind what the store's little buddy tries to sell you on the more expensive or top of the line product when you may never get the actual performance in the first place. Also, and MORE importantly, what good is a projector capable of 0.025 lumens uncrushed black light output if your environment has 10 lumens of ambient lighting present?