How Bright Should Your Projector Be?

Understanding the projection details

It is becoming more and more common for people to just think that any projector will work in any room for any type of viewing. This is just not the case.

Image Quality

First, understand that a projector’s brightness rating isn’t the bottom line for what gets to your screen. You can’t usually get 3,000 usable lumens out of a projector rated for 3,000 lumens with the kind of image quality you want for a dark-room home theater. Most often, you only get about half of the rated brightness from almost any projector when it is adjusted for the best video quality.

Exceptions

There are exceptions to this rule, but it is always a good rule to divide the rated brightness by 50% for a close estimate to how much real world brightness you should expect. But, what does the resulting 1,500 or so lumens of that 3,000 rated-lumens projector actually provide to you in terms of screen size? Well, it all comes down to math. And not even hard math.

Home Theater

For home theater use in a dark room, 13-18 lumens per square foot is the recommendation. Some people like a bit more punch, and 20-25 lumens is more than enough to deliver that.

Looking at some common screen sizes, the square footage, and actual brightness needed for 18 lumens per square foot is as follows…

Screen Diagonal (in inches)	Total Square Feet	Lumens Needed
100	30	540
110	36	650
120	43	774
133	52	936
150	67	1,206

Most Important

So, you can see, that even fairly dim projectors can deliver a 100-inch diagonal image that will be punchy and bright enough in a dark room.

The problem is, that once you start adding light to the room, things change dramatically. Projectors can’t project black. This is the most important thing to understand. So, if a white wall is lit with light in the room, then that will be ‘black’, and the projector needs to get much brighter than that wall to make it appear as black.

Correct Lumens

This means that the 18 lumens you needed in a dark room which delivered a 1,000:1 contrast ratio, will now need to be 60 lumens in your lit room to give you a 50:1 contrast ratio (or less).

So, your 100-inch diagonal now needs more than 1,600 lumens to be usable, and it won’t give you a great image, but a usable image. Your 120-inch diagonal will need almost 2,600 lumens. The 150-inch screen will need over 4,000 lumens.

Not advertised lumens… Real world, calibrated, color corrected, lumens.

Wired Or Wireless?

Today’s premium Bluetooth wireless headphones are so awesome, sound quality is virtually indistinguishable from wired versions of the same thing.

The sense of freedom, no longer being physically tethered to a device, and so on — but why? This is a no-brainer: If you can afford wireless headphones, buy them. After all, almost every pair of wireless headphones on the market today also ships with a wire, so you still get the best of both worlds.

That said, there are still two big reasons to consider wired headphones. If you’re a serious musician, sound engineer and/or audio tech, you’re going to want wired headphones for the higher quality audio and consistently better sound – no matter the conditions.