If you’re sensing a “but”, then you’re getting the hang of this home theater stuff. You can simply use the horizontal lens shift controls to push the image on the screen, to scoot it over that one foot or so to the left. Horizontal lens shift allows you to physically move the image, to basically scroll it left or right. Instead, it moves the image up, down, left, and right, while maintaining the resolution and fixed aspect ratio, like magic.Ĭompared to our example above, you’ve been forced to mount the projector a foot off the center-line, but instead of rotating the projector to face the center-line of the screen, you point it directly at the wall ahead, so that when you turn it on the image is (who’d have guessed) a foot too far to the right. Thus, it doesn’t open the image quality up to degradation from post-processing or warping.
How Lens Shift WorksĪs opposed to Keystone correction, Lens Shift is a much more elegant solution in that it is a physical manipulation of the light, not the source image. Notice, the image is a near-perfect rectangle now.īut what if you could mount the projector off the center-line but not rotate it at all? Enter Lens Shift. This is the projector’s image after adjusting the keystone options.
Notice, the image is pretty distorted, as none of the corners are parallel to each other. Example of Keystone Correction This is the projector’s image before adjusting the keystone settings. If it’s mounted a foot to the left, you have to rotate it to aim at the center-line of the screen, and that will make the light on the left side of the screen spread out more–warping that leads to the left side of the image being physically taller than the right, putting you in a position where keystone correction is your only tool. If the projector is mounted on the center-line, it’s pointed straight forward. Like anything good, keystone correction is best used in moderation: when a mild offset of the projector causes a little warping of the image.įor an offset projector, this means you will want to be minimizing the rotation of the projector as much as possible. This is going to play havoc with the final resolution and may be especially problematic when it comes to text and other fine details (like if you’re projecting a computer screen to do work.)īut it’s not all bad news those problems with resolution wonkiness really only reveal themselves when you put yourself in a position in which you have to crank the keystone correction all the way up to eleven. Because of that, it’s taking the image and reprocessing it some. How Keystone Correction Worksįirst, and most importantly, you should understand that keystone correction is a digital manipulation of the image, not the physical light source. Examining a few more details about each is helpful for understanding the solution to our off-center projector problem. At first glance, they may seem like the same thing–it’s all manipulating the image to fit the screen right? There are options for dealing with this, tried and true methods that fall into one of two categories: lens shift and keystone correction. What If You Can’t Physically Center a Projector?
PROJECTOR CENTRAL SCREEN CALCULATOR INSTALL
Beyond fans and electric lights, physical skylights, air vents, recessed speakers, any of that can make your install a little less than straight forward.
Look, there’s no getting around the fact that mounting a projector on the center-line is physically easier–with a little string or a trusty measuring tape you can mark a spot on the ceiling by eye, fine-tune the measurements to make sure it’s centered, adjust as necessary and get the drill out.īut plenty of things can get in the way. How Do you Center a Projector on the Screen? Horizontal lens shift? Keystone correction? What’s going on with all this terminology, and how do you use those answers to understand if you can just mount the thing off to the side of the ceiling fan or recessed lighting blocking the center-line already? I’m glad you asked. Not all projectors have horizontal lens shift, which is not the same as keystone correction.īut already I’m sure you have more questions than answered. It’s easy to make assumptions because that’s one less question you need answered, right? But today we’re going to take a minute to talk about a question that many people forget to ask: do you really need to center your projector when you install it? What about pico projectors? Does the same rule apply (more on that here)?Ī projector does not have to be centered on the screen if the projector has the horizontal lens shift range to move the image onto the screen. It’s easy to get caught up in all the details of building the perfect home theater, all the file formats, cables, questions on resolution, wireless video, etc.
0 kommentar(er)
