How We Test Projectors | PCMag

At PCMag, our goal for projector testing is to follow a test methodology that does two things well. First, the process lets us report meaningful information based on objective results, in the form of quantitative measurements and carefully defined qualitative observations. And second, it defines a consistent test procedure that ensures our results are fully comparable from one review to the next.

---

The Projector Test Procedure: Getting Started

When testing projectors, one thing’s key before we even start: It’s important to let the equipment warm up thoroughly to ensure stable performance. Our first step is to turn on the projector and make sure it will stay on continuously by disabling any settings that might turn it off or put it in an idle (or sleep) mode.

(Credit: Joseph Maldonado)

During the 30-minute warm-up time, we run through some preliminary setup steps. This includes connecting cables to video sources, setting up a Wi-Fi connection to an internet-connected network for streaming when needed, and positioning the projector at the right distance from the screen to get the image size we need for testing. For projectors that offer built-in streaming or a bundled dongle, we also run any needed setup routine for the streaming itself. (That might include adding user names and passwords to apps for Netflix and a few other popular streaming sources.) The choice of additional apps depends on which are available and what features the projector offers that need testing. For projectors that support IMAX Enhanced, for example, we look for a Disney+ app.

(Credit: M. David Stone)

For projectors that have auto-setup features for image geometry—whether just automatic vertical keystone adjustment or a full set of features that can include obstacle avoidance, screen fit, and more—we first test those features to see how well they work. Then, we turn them off, because digital adjustments affect image brightness and can add artifacts. We also test the autofocus feature (if there is one) and leave it on unless we find we can improve the focus manually.

After turning off the auto-setup features, we set all projectors that include an optical zoom lens at the maximum wide-angle setting, which delivers the largest image size and highest brightness, then adjust the image to the right size by moving the projector closer to or further from the screen. For projectors that include a digital zoom, we set it at 100% to take advantage of the entire imaging chip.

For most projectors, we set the image size to 2 meters (78.4 inches) across, which matches the width of a 16:9, 90-inch diagonal screen. (The height and diagonal size will vary depending on the projector’s native aspect ratio.) For projectors that can’t throw a bright enough image to be usable at that size or that are so bright that they can light up a substantially larger screen, we adjust the size as needed and report the image size we used.

---

More Preliminaries and Initial Setup

We also browse through the on-screen menu system to familiarize ourselves with the menus and controls on both the projector itself and any included remote control. Another reason for browsing through the menus is to spot any settings that might require testing beyond what we normally do (with a given setting both on and off, for example). We make sure that any features that might affect our results are set properly.

(Credit: Joseph Maldonado)

Finally, we set our local image sources—computer, Blu-ray player, or both—to the appropriate resolutions for testing. We set the computer to match the native resolution of the projector, which avoids artifacts introduced by the projector scaling the image up or down. We normally set the Blu-ray player to negotiate the resolution automatically; however, we check to see what resolution and dynamic range it negotiated, to make sure it’s what we intended. If the projector claims a native 4K resolution, for example, and the resolution for the connection shows as 1080p, we set the Blu-ray player to connect only at 4K to confirm whether it can actually connect at the claimed resolution.

Once the projector is warmed up, we use a series of setup screens from the venerable DisplayMate testing utility to confirm that the projector is properly focused and set to show the entire image without losing any pixels on the outer edge. We run this test for both the PC and the Blu-ray player (using images on a disc) because some projectors treat input from a PC differently than input from a video source.

---

Testing Projectors: These Are the Basics

Because there’s a great deal of overlap among data projectors, home entertainment projectors, home theater projectors, and gaming projectors, we run all projectors through both our core data-projector and video-projector tests. We skip tests for a given projector only if it lacks an appropriate connector or support for a given input resolution. For example, we don’t test input lag at 4K UHD (3,840 by 2,160 pixels) and 60Hz for a projector that’s limited to 4K UHD at a maximum of 30Hz.

(Credit: Joseph Maldonado)

Our Core Tests Defined

For our core data and video tests, we use the most basic screen possible: a white screen (gray screens effectively increase contrast ratio) with a 1.0 gain. (Higher gains concentrate the reflected light into a narrow cone, making the image brighter within that cone than it would otherwise be.). We also test on this screen without any ability to minimize the effect of ambient light (by scattering overhead light in all directions, for example, while reflecting light from the projector toward the seating area). The overall point is to make sure our observations are based strictly on the projector’s abilities, as opposed to being enhanced by the screen we’re using.

Our data tests use additional DisplayMate test images, plus a PowerPoint file with business graphics and photos. Each image is designed to test a specific aspect of a projector’s imaging capability. As a group, they highlight any image-quality problems that a projector (or other display) may have. The full set thoroughly vets the projector’s abilities for business and education applications. 

(Credit: Joseph Maldonado)

Our video tests center on 1080p and 4K UHD, which are the two video resolutions most relevant to real-world use today. Arguably more important for image quality, however, is dynamic range, which can be either standard dynamic range (SDR) or high dynamic range (HDR).

Although either resolution can be paired with either level of dynamic range, 4K video sources today are most likely to be HDR, while 1080p sources tend to be SDR. If you’re watching at 1080p HDR, it’s often because the original material is 4K HDR, and either the source you’re connecting to is downconverting it to 1080p HDR, or your projector can accept 4K HDR input and downconvert it by itself.

For all projectors, we view a set of photos from the DisplayMate Multimedia Edition, as well as movie clips from 1080p SDR Blu-ray discs. The individual photos and clips are chosen to highlight how well the projector handles motion, skin tones, and memory colors. The latter include grass, sky, the colors of common fruits (such as oranges, which many projectors can’t reproduce well), and other common real-world colors. The tests also show the level of contrast, shadow detail, and black that each projector offers. We report on these issues, as appropriate, as well as any other relevant observations. 

For projectors that support HDR, whether the projector offers native 4K resolution or 1080p, we also view a selection of the same scenes from the 4K UHD HDR versions of the same movies on disc. For this test, we check to ensure the player and projector negotiated a 4K UHD HDR connection for models that support 4K input or a 1080p HDR connection for models that don’t.

A Side Note About HDR

One complicating factor is that there are several HDR protocols, and both the source and the projector have to have at least one in common. The two that we see most often in projectors are HDR10, which all HDR projectors support, and HLG, which the majority support. However, more and more models are also adding HDR10+ and Dolby Vision, two versions of HDR that offer improvements over HDR10 and HLG, and that many streaming sites support.

(Credit: Joseph Maldonado)

Our formal tests using movies on disc use the identical scenes for all projectors. They also let us evaluate how well the projector handles the same scenes for SDR and HDR versions of the same movies, and see what differences, if any, there are between the two. However, the HDR version in these tests is limited to HDR10. To judge how well the projector handles HLG, HDR10+, and Dolby Vision, we run additional tests with streaming sources. (Those tests are described below.) The streaming tests also cover IMAX Enhanced mode, as well as Filmmaker mode for models that offer them. Briefly, IMAX Enhanced offers an assortment of features typical of IMAX theaters, any of which may or may not be supported in any given implementation. Filmmaker mode, meanwhile, turns off enhancements like motion smoothing, with the goal of reproducing as closely as possible the director’s intent for how the movie should look.

For projectors with a native resolution lower than 1080p, we use the same discs as for testing 1080p projectors. We leave the Blu-ray player set to Auto to let the player and projector negotiate a connection at the highest resolution the projector can accept. For 1080p connections, the projector then downscales the image. For lower-resolution connections, the Blu-ray player handles the downscaling.

Input Lag and 3D Testing

We measure the input lag at 1080p/60Hz for all projectors, using a Leo Bodnar Video Signal Lag Tester, often called simply a “Bodnar meter.” 

(Credit: M. David Stone)

For 4K projectors, we also measure the lag at 4K/60Hz. For those models—mostly gaming projectors—that support shorter lag ratings at 1080p/120Hz and 1080p/240Hz, we measure at those settings, too.

(Credit: M. David Stone)

For home theater and home entertainment projectors, in addition to the above tests, we connect the projector to a FIOS box with a DVR feature to view recorded clips from movies, sports, and both live and filmed TV shows. Using recordings ensures that we’re looking at the same selection of clips for each projector.

Stereoscopic 3D isn’t as pervasive as it once was, but it’s still available on most new DLP models and at least some LCD models, particularly those meant for home entertainment. In many cases, it works only with input from computers, which limits its usefulness. However, many projectors support Full HD 3D, which will work with 3D Blu-ray discs, set-top boxes, and streaming services.

For projectors that support Full HD 3D, we run our 3D tests using a Blu-ray disc. The clips are chosen to highlight how well the projector handles the same aspects of projection that we examine for 2D video, plus the 3D-specific issues of crosstalk and 3D-related motion artifacts.

Evaluating Streaming Features

For streaming projectors, we look for a Netflix app so we can check whether it works properly with the remote, since some are designed for mouse or touch-screen control. We also view at least several minutes of a movie to see whether the projector tends to skip over frames with a sudden jump every couple of minutes.

(Credit: M. David Stone)

For streaming projectors that support HLG, Dolby Vision, HDR10+, IMAX Enhanced mode, or Filmmaker mode, we also make the effort to test each mode they support. We say “make the effort,” because running these tests is a little tricky. Two projectors that both support the same selection of HDR modes will often wind up negotiating different connections with the same site, so we sometimes can’t find an appropriate site to test a given mode.

Beyond that, streaming sites often change their available content, and even change which content is available using a feature like Dolby Vision. That prevents us from being able to test with exactly the same streaming material on every projector in the way we can test the same disc-based movies in every case using a Blu-ray player. That lack of strict consistency for our streaming tests is why we refer to them as part of our informal testing.

The same necessary variation is true for our informal testing in a family room that has a skylight and windows to let us see how the picture holds up in real-world use. Also in the category of informal testing is taking a look at any unusual feature a projector might offer—anything from a bundled screen to microphones for karaoke. In those cases, we run ad hoc tests as appropriate.

---

In Sum: A Mix of Repeatable and Informal Tests Is Healthy

Using the same meticulous tests for every projector wherever possible, combined with informal testing where necessary and ad hoc tests for uncommon features, lets us compare and rate each model with confidence. It also lets our expert analysts authoritatively recommend the best projectors for your home and business needs.

About M. David Stone

Contributing Editor

Most of my current work for PCMag is about printers and projectors, but I’ve covered a wide variety of other subjects—in more than 4,000 pieces, over more than 40 years—including both computer-related areas and others ranging from ape language experiments, to politics, to cosmology, to space colonies. I’ve written for PCMag.com from its start, and for PC Magazine before that, as a Contributor, then a Contributing Editor, then as the Lead Analyst for Printers, Scanners, and Projectors, and now, after a short hiatus, back to Contributing Editor.

Read M. David’s full bio

Read the latest from M. David Stone