Home theater projectors: 6 things to know before you buy

Projectors are better than TVs. There, I said it. I mean, the picture quality on a projector isn't as great as a TV at the same price. And you need a dark room. And they're kinda loud. But how else are you supposed to get a 100-inch image for under $1,000?

Home theater projectors range in price from a few hundred to tens of thousands of dollars, but you don't need to spend that much to get a high-quality image. But what features do you need? What technology is best? How do you decode UHP, ANSI, LCoS, DLP and countless other abbreviations and acronyms?

Well friends, buckle up and turn down the lights, you've come to the right place. We're going to answer those questions and a few you might not have known to ask. But if you want to skip all that and just get our recommendations, check out the best projector for home theater in 2020.

1. Lovely lumens

One of the most important specifications for projectors is "lumens," which describes how much light a projector can create. This, in turn, determines how bright the image is and how big you can make it. There are a lot of problems with this spec. For one, other than the distinct "ANSI lumens" there's no agreed-upon way to measure lumens. One company's 3,000 might be another's 3,500. Most manufacturers don't specify ANSI lumens, which would be easier to compare across brands.

You can compare broad strokes however. Generally speaking a 3,000-lumen projector is probably brighter than a 2,000 model. But if you're trying to choose between 3,000 and 3,100 lumens, good luck. Even if those numbers were accurate, that little of a difference probably won't be visible anyway.

So how many lumens do you need? Well there are some considerations we'll get to, but generally speaking you probably won't regret getting the brightest projector you can. Other aspects, like color accuracy, contrast ratio, and more, are vital, but for an initial sweep of potentially promising projectors, see what kind of lumen output is available in your price range. It's worth keeping in mind that you can usually turn down the brightness of a projector, but you can't turn up an otherwise dim projector. That is, unless you make the image smaller. 

To give you a rough idea, a 2,000-lumen projector will create a bright, watchable image on a 100-inch screen in a dark room. A 1,000-lumen projector will be "fine" but won't really punch. 3,000 and over will be very bright, perhaps too much so for some viewers. These are all very rough numbers which, again, are hard to compare since the specs themselves are suspect. If you look at our reviews, and what results we've gotten with measurement gear, it might give you a better idea what you're looking at. 

If this is frustratingly vague advice, that's sadly the state of things.

2. Laser, lamp or LED?

Projectors create light and image separately. A light source creates the light, which is then focused on an image-creating chip. Modern projectors use one of three technologies as light sources: LEDs, lasers and UHP (ultra high pressure) lamps.

UHP lamps, which are basically high-powered light bulbs, are by far the most common. These are capable of creating a lot of light and have the added bonus of being fairly inexpensive. The downside is they degrade over time. A UHP projector will never be as bright as that first time you turn it on -- until you replace the lamp. 

This aging is a slow process though. We've reviewed several that, in certain modes, have lamps that can last 15,000 hours before you need to replace them. So if you watch the projector for four hours every night, that means the lamp will last over 10 years. Prices vary, but typically a new lamp will run you $100-$300. More expensive projectors have more expensive lamps. Go figure.

Relatively new to the home theater projection scene are LED and laser light sources. These are cooler than UHP lamps in both senses of the word. LEDs and lasers in projectors function in similar ways and some projectors use both, so for our purposes we'll group them together. They're far more efficient than UHP lamps but cost a lot more to create the same amount of light. If you had a $1,000 lamp-based projector and a $1,000 LED or laser projector, the UHP-lamp projector is going to be brighter. There are lots of affordable LED-based projectors available today but they're usually quite dim. That probably won't be the case forever, but it is right now.

I absolutely understand the appeal of LED/laser, especially since they're often rated for 30,000 hours. Not having to replace the lamp, aka spend money on something you've already spent money on, is completely understandable. However, the price/performance ratio of UHP lamp projectors still can't be beat. Having to spend ~$150 every 5 to 10 years doesn't seem outrageous. You also have a much wider range of UHP projectors available, from many different companies.

3. Chip tech

After the UHP lamp/LED/laser creates the light, some kind of chip manipulates that light into an actual image. There are three technology types when it comes to projector chips: DLP, LCD and LCoS. We go into these technologies into greater detail in DLP vs LCD vs LCoS: Projector tech pros and cons, but here's a short list of the highlights:

DLP

• Available from numerous brands
• Widest range of prices, from budget to high-end
  
• No motion blur (aka sharpest picture)
• Contrast ratio only average
• Color is often mediocre, though that's not inherent in the technology.

LCD

• Budget to midrange projectors, mostly from Epson
• Motion blur
• Contrast ratio is often poor.
• Color can be better than most DLP projectors.

LCoS (SXRD and DILA)

• Mid- to high-end projectors including Sony and JVC
• Motion blur
  
• Best contrast ratio
• Color is often very good, but that's more to do with being found in higher-end projectors.

The image chips are one of the most confusing, but also most interesting, aspects of projectors. Despite dozens of companies making projectors, the chips are almost all made by just four companies. Every DLP-based projector uses a "light engine" made by Texas Instruments. This includes the chip and the color wheel (to make all the colors you see). How it's implemented in a case, the overall airflow, what lamp is used, how the settings are tweaked and more, are often done by the projector maker, aka the name on the outside. Some companies just use a reference design and slap their name on it. Others might use the base reference design, and then tweak it to their specs. That all said, two DLP-projectors that cost the same, but are from two different companies, are going to look more similar than different. Probably not identical, though. There's still a lot that can be tweaked.

For LCD, Epson is by far the biggest name. Lower-end models typically have very poor contrast ratios. It's just harder to get a good black level with LCD, something that's true with TVs as well. However, Epson has come a long way in recent years. Its Home Cinema 2150, for instance, had a better contrast ratio than many competing DLP projectors. They're all three-chip designs, as in there's a separate chip for the red, green and blue components of an image, so it's possible for them to have better color compared to many DLP projectors, which usually rely on a spinning color wheel. This largely varies per projector, however.

In terms of overall picture quality, LCoS is usually the winner. The two biggest manufacturers of LCoS (or liquid crystal on silicon) chips are Sony, as SXRD, and JVC, as D-ILA. These are found in more expensive projectors, even the cheapest being a few thousand dollars. Their contrast ratios are significantly higher than either DLP or LCD. They're all 3-chip designs, so they typically have excellent color as well.

4. Placement

Now that you've got the basic tech down, it's worth considering where in your house you're going to put the projector. That might limit which projectors you can buy, as some might not fit where you want them to. 

Affordable single-chip DLP projectors typically have very little, if any, lens shift. This means that you can't adjust the height of the image without moving the projector. These units also typically have an upward throw angle, meaning the bottom of the image is at or above the top of the projector. Because of this, they have to be mounted either on the ceiling, or on a coffee table. It's difficult, if not impossible, to place them behind a couch on a stand and still have a normal-looking image.

Many LCD and nearly all LCoS projectors have lens shift, so they'll work in far more places.

You also need to consider how far back you have to place the projector to create a large-enough image. Projectors have a limited zoom range, though some are greater than others. To create a specific size image, aka the size of your screen, there will be a limited range of distances that will work -- a spec typically listed as throw distance. For inexpensive projectors, this "sweet spot" could be as narrow as a few feet. Higher-end models might be far greater. Typically these numbers, along with a distance calculator, are available on a manufacturer's website.

Read more: Projector setup tips: How to get the biggest, best image for movie night

Watch this: Six things to know about home theater projectors

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5. Other features and what they mean

Just like TVs, projectors have numerous features to mire you down in acronyms and marketing. Some of these features have real value, others, not so much.

Automatic iris: A mechanized iris is a common feature found on both inexpensive and expensive projectors. During dark scenes, the iris closes down, making the entire image darker. On bright scenes, it opens back up for maximum brightness. This is a bit of a cheat, as the contrast ratio at any one moment is the same (and almost entirely determined by the image-creating chip or chips). However, it can make an average or poor black level, and the corresponding gray-ish shadows, less noticeable by making them, and everything else to be fair, darker during dark scenes. Some versions of this technology are slow, meaning it takes a moment for them to catch up to the video, resulting in a noticeable pulse to the brightness of the image. If you don't find the iris's action distracting, there's no real downside to having one or using it. Not a huge benefit either, though.

Dynamic lamp: Another way to achieve the same dynamic dimming of the image brightness is by reducing the power on the lamp. This has the added benefit of extending its life. Just like with the iris, on certain content you might notice the projector dimming on dark scenes. On other projectors, you might notice the fan speed ramping up and down at the same time. Like the auto iris, this doesn't improve the native contrast ratio, as in the contrast during any single moment on screen, but it does help a bit to make darker scenes appear somewhat darker. As long as you're not bothered by it, there isn't any downside.

4K: Great picture quality is reliant on many factors, including contrast ratio, brightness, color, and yes, of course, resolution. The latter, being the easiest to understand and quantify, typically gets far too much weight when comparing projectors. 4K on a 100-plus inch screen is very cool, but it is just one aspect of a projector's overall performance. Personally, I'd take a bright projector with accurate color and a great contrast ratio over a dim projector with a poor contrast ratio that happens to be 4K. 

And unlike 4K TVs, which are quite affordable these days, 4K resolution projectors are still relatively expensive, starting at around $1,500.

3D: Many projectors are still 3D-capable, though they rarely come with the glasses. If you're super into 3D, you'll be able to find lots of options. If you're not already into 3D, I can't imagine now is the time you'd get into it.

Lens shift: As mentioned above, being able to adjust the height of the image separate from the height of the projector is very handy. It allows for a wider range of placement options without having to resort to the quality-ruining potential of digital keystone adjustment. So lens shift is certainly a benefit, though if you already know exactly where your projector is going, and don't need lens shift to put a projector there, it's not a big deal.

Short throw: This isn't really a feature as much as a category of projectors. A much shorter throw distance means so you can place them closer to a screen for the same size image. For certain rooms it's very useful. The opposite would be a long throw projector, which, as you'd guess, means you can place it much farther from the screen than a typical projector.

Motorized lens: This can mean motorized focus, motorized zoom or both. Not vital, though handy. Motorized zoom, especially if you can save preset sizes, means you can fill a wider-than-normal screen for movie nights, then zoom down to just fill a 16:9 portion of the same screen for TV shows.

Game mode: For gamers, a mode that lowers the input lag can help tremendously. First-person shooters, racing games, platformers, really anything that requires precise timing between button pushes and what's happening on screen. Not all game modes are made equal. DLP projectors often have low input lag, and especially low for game modes. LCD and LCoS projectors are more varied.

HDR: More and more projectors are offering HDR-compatibility. Don't expect a lot. Done right it can look a little better than the non-HDR version of the same content on the same projector. It's just not as big of an improvement as it is with televisions.

6. Don't forget cables

Most new projectors have a USB connection that will let you power a streaming stick which plugs into an HDMI input.

Otherwise, you're going to need to run a long HDMI cable. These don't have to be outrageously expensive. Make sure they're able to handle the resolution and frame-rate you want over their distance. If you're sending 4K, for example, you're going to need a better cable than if you're sending 1080p.

One option to consider is fiber optic HDMI cables. These have HDMI connections at either end but send the signal optically. These are typically thinner than long-run copper cables. Monoprice has some options for around $2.50 per foot, compared to $0.70 for an equal-length, equally-capable copper cable.

Another option is wireless. These are typically more expensive than cables, and might not offer the resolution/frame-rates you're looking for. Some will drop the signal if you walk between the transmitter and receiver, and won't work if placed in a cabinet.

There's plenty of other stuff to consider in your projector purchase but that sums up the basics. For more details, check out CNET's reviews of home theater projectors.

As well as covering TV and other display tech, Geoff does photo tours of cool museums and locations around the world, including nuclear submarines, massive aircraft carriers, medieval castles, airplane graveyards and more. 

You can follow his exploits on Instagram and Twitter, and on his travel blog, BaldNomad. He also wrote a bestselling sci-fi novel about city-sized submarines, along with a sequel.