Why You Can Trust CNET How Important Are Lumen Ratings When Buying a Projector?
From bite-size portable PJs to big home theater light throwers, here's much brightness do you actually need.
One of the most common specs used to compare projectors is a measure of how bright each model is: lumens. This is because, in theory, a 1,000-lumen projector will be brighter than a 500-lumen projector. With projectors, the brightness not only determines how bright and easy to see the image will be, but also how large the image can be. A brighter projector can create a larger image without being too dim to watch.
Frustratingly, it's a lot more complex than that. If you're interested only in the broad strokes of how many lumens you need in a projector, the sections below will cover that. If you're interested in digging a little deeper, including why the numbers can only ever be used as broad guidelines, further sections will, ahem, illuminate the subject more.
Read more: What are Nits, and Why are They Important?
Under 500 lumens
The smallest and cheapest projectors typically have 500 or fewer lumens. These often-battery-powered pico projectors aren't designed to create huge images, despite what their marketing claims. A TV-size image will be watchably bright, but a 100-inch image will be very dim. Watchable in a totally dark room? Technically, yes, but it won't look great.
For reference, the hand-holdable AAXA P8 pico projector is rated at 430 lumens. During our testing, it was able to create an image that was roughly 25 nits on a 100-inch screen. For comparison, many 65-inch TVs can create over 1,000 nits. Even if you make the AAXA's image 65 inches, it's still only creating an image that's roughly 61 nits. Other portable projectors, especially the ultra-cheap variety, are even dimmer than the P8.
Now, for their size and convenience, this is all totally fine and expected. Just don't believe the marketing of wall-size, TV-bright images from something the size of a book and cheaper than a cellphone.
Around 1,000 lumens
The next step up from the tiny portable projectors are typically still "portable" but are somewhere between the pocket-size picos and the backpack-carriable home theater projectors. Overall, this class of projectors is typically designed for occasional movie night use and usually use LEDs or lasers as their light source. Take, for instance, the Epson Epson EpiqVision Mini EF12 shown above. It has a claimed 1,000 lumens.
Creating a 100-inch image is still a bit of a stretch for something rated at 1,000 lumens. They are certainly not as dim as the low-lumen picos, and in fact the Epson EF12 is capable of roughly 3x the light output of the AAXA P8 for instance, but for their price and size, these types of projectors are more about convenience and form factor than outright performance.
Some ultra high-end projectors are in this lumen range as well. However, they're designed for light-controlled rooms and usually have extremely high contrast ratios that make their images look more punchy and lifelike than is possible with brightness-first projectors.
Around 2,000 lumens
For many years, 2,000 lumens was considered a lot for a home projector. Now, it's so common, it's practically the baseline -- take, for instance, the Editor's Choice-winning BenQ HT2060. It's rated at 2,200 lumens, which creates an extremely watchable 100-inch image, though you'll still want a light controlled room. This is the perfect range for a traditional "home theater" projector, even if home theater just means your living room.
Shrinking the image down to 65 inches to compare with a standard TV size, the HT2060 could create around 262 nits in our testing (which is color and color temperature accurate, unlike many manufacturer measurements).
As long as you can control the light in your room or are willing to buy an ambient light-rejecting screen, anything over 2,000 lumens will work for screens around 100 inches. You could create a 150-inch image, though it will be fairly dim, less than half as bright as the same projector creating a 100-inch image.
Over 3,000 lumens
Increasingly, there have been more and more -- and more affordable -- projectors with over 3,000 lumens. For instance, the $500 Epson CO-FH02 is rated at 3,000 lumens and is the brightest projector we've ever tested. It can produce over 500 nits creating a 65-inch image. Its contrast was quite poor, however, so despite its brightness, it didn't look great. At the other end of the performance scale, the BenQ TK860i (review coming soon), is rated at 3,300 lumens and looks really good.
On one hand, I've never reviewed a projector that was too bright. All of them, when creating a 100-inch image, will be dimmer than even a cheap TV. They also create an image way bigger than any TV, which is the point, and it's awesome. So the advice of "get the brightest projector you can afford" isn't wrong per se, but it's incomplete. Brightness is just one aspect of performance. A crucial one with projectors, for sure, but if you put Epson CO-FH02 next to the 1,500-lumen Sony VPL-VW325ES we reviewed a few years ago, no one would say the Epson looks "better," just brighter.
A comparison could be made to cars. Is the fastest car in the world the "best" car? Of course not, because the best car in the world is the Mazda Miata, and if it was a projector it'd barely be rated at 1,500 lumens.
Which is to say, once you get above 2,000 lumens there's a lot more at play than just brightness. A 3,000 lumen projector might not look as good as a 2,000 lumen projector, it will just be brighter. Maybe that's what you need or want, but not always. Then there's the fact that no matter what a projector is rated, its actual light output will be far lower. Which brings us to…
Actual Lumens (ANSI, ISO and CVIA)
All projector manufacturers inflate their lumen ratings. Some by a little, some by a lot. In the most general sense, a 3,000 projector is probably brighter than a 1,000 lumen projector, but 1,200- and 1,300-lumen projectors are probably indistinguishable when it comes to brightness.
For an outdoor movie night, brightness is vital so you can see anything at all. On the other hand, spending a lot doesn't make sense if you're only using it occasionally.
Worse, comparing lumen ratings between different companies is even more difficult, as they are probably differently different, if that makes sense. One might be 10% wrong, the other 30% wrong, for example. Also, if you set up a projector correctly, in terms of picture mode and color temperature, the actual brightness on screen will be even lower than what's claimed, since a manufacturer is going to use the brightest settings for the basis of their numbers, not the settings that produce the best image.
Some companies use ANSI or ISO lumens. These are different methods of measuring brightness. Each has specific rules for how the measurements should be taken. Theoretically, these are a more accurate measurement and are more comparable to other ANSI or ISO measurements (though not perfectly and not against each other). There are still a number of variables that make the exact comparison difficult, least of all a company outright lying and saying their lumens are ANSI when they're not.
Occasionally, you'll see CVIA lumens, or Chinese Video Industry Association, which developed its own way of measuring lumens. It's similar to ANSI but makes the color temperature more variable. As such, CVIA lumen ratings are likely higher than ANSI ratings (and in my opinion, less accurate). Like all lumen ratings, you can make general assumptions about CVIA ratings across different companies, but not against non-CVIA lumen ratings. As in, a 3,000-CVIA lumen projector might be a bit brighter than a 2,500-CVIA lumen projector, but it might be the same as a 2,500-ANSI lumen projector. They might all be brighter than a 3,000 non-CVIA, non-ANSI lumen projector, or they might be dimmer. It's impossible to say without a third party measuring it.
We measure the brightness of all the projectors we review, along with other aspects of performance, so at the very least you can compare our brightness numbers.
As well as covering TV and other display tech, Geoff does photo tours of things like cool museums and locations around the world, including nuclear submarines, massive aircraft carriers, medieval castles, epic 10,000-mile road trips and more. Check out Tech Treks for all his tours and adventures.
He wrote a bestselling sci-fi novel about city-size submarines and also Budget Travel for Dummies. You can follow him on Instagram and YouTube.