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Osman Blunt
Hey tjluoma, really appreciate you sharing this, I've found this super useful. Apologies if this is a newbie question, but I'm wondering if there is a way to capture a pre-selected boundary for the screenshot (I want to grab a specific area of the screen, convert the image to text, and then copy to clipboard). My gut says I would need to change the /usr/sbin/screencapture -i -c in the shell script, but I'm not 100% sure. Any suggestions?
The Wemax frame is made of aluminum and is produced with acceptable tolerances resulting in slight gaps in the mitered corners, but the construction materials result in a strong and sturdy frame that is easy to assemble. The screen material itself is installed and tensioned using fiberglass tension rods and springs that attach to the aluminum frame. The Wemax screen took me approximately 1.5 hours to construct using the included instructions and I had no issues getting proper tension on the screen.
The Formovie screen had clear, easy to follow instructions and a lightweight but high quality aluminum frame. Unlike the rest of the screens the Formovie screen material is tensioned using screws with fiberglass tension rods and aluminum tension bars which are so much easier to use than springs, and there was absolutely no doubt that the screen would be perfectly tensioned and wrinkle free. The Formovie screen material did have a noticeable smell that reminded me of a newly purchased inflatable raft, but that smell dissipated in just a few hours. The Formovie build time was the least yet at just an hour and 15 minutes and it was by far the easiest screen to put together.
I contacted Brian at projectorscreen.com about it and he was just as confused as me. We exchanged measurements, compared them side-by-side to other screens that we had on hand, and something was clearly wrong with my screen. Brian overnighted me the material from one of his floor room samples and sure enough, they were completely different, you can see the old screen on the left and the retest on the right. Not only is there a night and day difference in ambient light rejection, gain, and black levels, but the replacement screen tensioned easily and without wrinkles.
To get a baseline value for gain, I used a 1.0 gain screen material from Vividstorm combined with a pure white image projected from a Formovie Theater ultra short throw projector. Measured using my lux meter with a directional attachment the 1.0 gain screen gave a value of 19.4 Lux at a distance of 1 meter.
Of the screens that listed a 0.6 gain, the Nothing Projector Screen was the brightest with a measured gain of 0.8, followed by the Vividstorm at 0.74, and then the Wemax at 0.69. The Spectra screen listed at 0.5 gain was about the same as the 0.6 gain materials with a measured gain of 0.77.
Gain and Black Floor are common measurements for any projector screen, but the main selling point of these screens is their ability to exclude ambient light, specifically from ceiling sources. To test this ability I used two banks of diffused LED lighting, one bank at a 45 degree angle from the center of the screen, and another at a 15 degree angle, and again calibrated the measurement using that 1.0 gain non ALR screen sample.
Starting with the 15 degree light, which would be similar to ceiling lighting over your couch, the Elite CLR3 screen rejected 49% of ambient light, then it was the Akia CLR2 screen with 51%. The Spectra, Vividstorm and Nothing Projector Floor Rising all rejected 60% of ambient light from 15 degrees, and the Nothing Projector fixed frame rejected 62%. After that the least expensive screen, the Wemax rejected 64%, and the highest light rejection value was the Formovie Fresnel screen at 70%.
Moving on to a much steeper 45 degree ambient light angle, the pure CLR screens improved significantly with the Akia CLR2 screen performing the worst at 62%, then the Elite CLR3 at 70%, the Wemax at 72%, then the Formovie at 76%, the Spectra at 78%, and the Vividstorm, Nothing Projector floor rising, and Nothing Projector fixed frame all had 80% rejection of light from a 45 degree angle.
The highest performing lenticular screen on paper was the Nothing Projector Screen with a gain of 0.8, black floor of 0.2 lumens, 62% rejection of 15 degree ambient light and 80% rejection of 45 degree ceiling light.
Unfortunately for the Akia, this same trend played out with every light source and every projector, and was even apparent in a room with nearly zero ambient light where you would expect a higher gain screen to perform better, but the colors just looked muted and washed out on the Akia in every situation. The Akia also had unexpectedly poor off axis performance with hotspoting on the near side of the screen and a noticeably dim area on the far side, so the Wemax easily took this round.
For the 45 degree ambient light test and the zero ambient light test, the Nothing Projector Screen had blacker blacks and whiter whites, but in the 15 degree ambient test the Wemax actually had a better black floor due to the fact that it was the lowest gain screen that I tested. Unfortunately, that also meant that the luminance was lower, which was more apparent using the Formovie projector than it was with the super bright AWOL.
Off axis performance was equal between the two, and both offer the super wide viewing angles that lenticular CLR screens are known for. If your room has more diffuse Ambient light, and your projector is sufficiently bright the Wemax screen might be a good choice, but in most situations the Nothing Projector Screen performed better, so it moves on to the next round.
And with the Formovie set up properly it significantly outperformed the Nothing Projector screen in both the 15 degree diffuse light and the zero ambient light test, and in the 45 degree ambient light test the results were confusing. The Nothing Projector screen clearly has blacker blacks and rejects more of that ambient light, but you can also see that there is a noticeable gradient of reflected light with the bottom of the screen having significantly better black levels, while the Formovie screen looks more gray, but black levels are uniform through the whole screen.
When testing the floor rising screens I attempted the same side by side comparisons, but the housing of the floor rising mechanism made it impossible to butt the screens together, so I found it was more useful to use the single screen footage and mirror them in Premiere.
The Projector Screen Store is pleased to offer Custom Size projection screens that are built to order! For more information please contact us at 1-800-637-3181, Chat with us, or send us an email at sa...@projectorscreenstore.com
ignoredSVG Pattern Test ResultsResults time! As shown in the tables, there were a few patterns that were not clean and caused the screen reader to repeat the alternative content. And while certainly annoying to users, it is better to hear duplicate content than none at all. Other patterns were much more problematic. For example, pattern 7 was missing the or the element for many browser/screen reader combinations. Likewise, pattern 10 was often missing the element. Worse still was pattern 6 which caused major issues, like not being able to even focus on the image, with NVDA and some mobile screen readers. For best AT coverage, it is probably best to avoid those three patterns until there is more support for them.
Based on these results, it is clear that not all SVG patterns are created equal when it comes to accessibility. Which pattern you choose to implement depends on many factors like how difficult it is to modify baked-in framework code and which browsers/screen readers you are targeting. But no matter which pattern you choose to use, be sure to set aside some time to do your own accessibility/user testing. As SVGs continue to dominate the visual world, it is important not to leave AT users in the dark!
Measurements for color and brightness uniformity were taken at 9 points across the screen, with the meter always perpendicular to the screen. A crosshatch pattern was used to line up to the desired measurement point, followed by a full field, 100% White pattern for the measurement. This assures repeatability as well as consistency across the screen. Color accuracy for the Elite was measured by assessing how close the white point/color temperature in each sector of the screen came to the D65 reference used by mastering studios. That point is defined on a CIE color chart by the x-axis position at 0.3127 and the y-axis position of 0.3290. Measurements taken for the Aeon CLR after calibrating the LS100 showed a maximum color uniformity error for the x axis of 0.004 across the screen (from 0.313 at Center Top to 0.309 at Left Bottom and Right Bottom. For the y axis, the maximum error was 0.003, with the Top Left at 0.330 and the Bottom Right at 0.327. These are considered well below the "Just Noticeable Difference" level for an observer described as "trained" (compared to a casual observer). Brightness uniformity was not nearly as tight across multiple points of the screen. At Center, the Aeon CLR measured its maximum brightness of 30.8 ft-L, and it dipped by 11.8 ft-L to the least-bright measurement of 18.9 ft, taken at the bottom-left. As described in the review, these deltas were likely attributable to the steep angle of the projected light and possibly the projector rather than any inconsistency in the screen surface. See the review for more detail.Elite Screens Aeon CLR Brightness Uniformity
(Foot-Lamberts)Elite Aeon CLR/
Epson LS100Elite Aeon CLR/
Long-Throw ProjectorMatte White Screen/
Epson LS100Top-Left19.646.2411.40Top-Center25.096.4018.54Top-Right20.676.2912.13Middle-Left24.696.5116.64Middle-Center30.786.9126.84Middle-Right25.126.5417.38Bottom-Left18.966.2812.77Bottom-Center24.936.4344.56Bottom-Right20.216.2613.82Elite Screens Aeon CLR Color Uniformity
(with Epson LS100) x axis (x target: 0.313)y axis (y target: 0.329)Top-Left0.3100.330Top-Center0.3130.329Top-Right0.3110.329Middle-Left0.3090.328Middle-Center0.3120.329Middle-Right0.3090.329Bottom-Left0.3090.328Bottom-Center0.3120.328Bottom-Right0.3090.328Buy a ScreenProjector Central has a list of screen dealers that we work with that can answer your questions and sell you a screen at a great price.