Build your own projector screen
WHY SETTLE FOR AN EXPENSIVE PROJECTOR SCREEN WHEN YOU CAN BUILD YOUR OWN FOR A FRACTION OF THE PRICE — AND WITHOUT LOSING OUT ON QUALITY?
WITH PROJECTOR PRICES starting at around the $800 mark, and easily exceeding several thousand dollars for a larger screen, they’re a huge chunk of the coin needed to build your own projector-based home theatre. But we’ve got a secret for you — there are several ways to build your own for a fraction of the cost, and you’ll be hard picked to notice any quality di erences unless you’re running a $15,000 projector. From blank walls, to special pain, to building a true frame with re ective material, we’re going to show you exactly how to save a massive amount when it comes to setting up your home theatre screen. Let’s start with the simplest — no screen at all.
WHAT IS ‘GAIN’
Most projector screens refer to their gain, and this simply measures the re ectivity of any screen or projection surface. e number itself represents the ratio of light that is re ected from the screen when compared to the light re ected from a standard while (magnesium oxide) board. A gain of 1. Will re ect the exact same amount of light as that from a white board, while 1.5 means it’s re ecting 1.5x the light of a white board.
Gain is measured directly from the front of the screen, perpendicular to the vantage point, where it’s at its brightest. is is known as the ‘Peak Gain at Zero Degree Viewing Axis’. However, if you move to an angle where the gain is only 50% of the peak value, you’re now viewing it from the ‘Half Gain Viewing Angle’. A screen with a lower overall gain will have wider Half Gain Viewing Angles, as they di use the light more evenly across the screen, making for a better experience when multiple people are viewing the screen.
Many people jump to the assumption that a high gain screen is best, as it’s pumping out a
brighter image. However, as mentioned, this means the optimal viewing angle is relatively narrow, so is best for theatres designed for one or two people. A 1.0 gain screen throws out light evenly in all directions, making it the better gain level for screens that will have several seats that are oblique to the screen.
A high gain can also have another negative e ect — it won’t show red, blue and green equally. is means that, as you move around the room, viewing the screen from various angles, noticeable colour shi s will be apparent.
Finally, a screen with a gain higher than 1.0 can display a phenomenon known as ‘Hot-Spotting’, where it’s brightest in the centre of the screen. Below 1.3, this shouldn’t be noticeable, but it can become an issue on high gain screens.
However, high gain screens have bene ts. ey’re especially useful in rooms where light leakage from outside occurs, as it will help to keep the image nice and bright.
PLAIN WALLS
I remember my very rst projector setup had absolutely no screen — I simply shone it on a matte white wall. Now this was a $1,000 720p projector, so I was working to an absolute budget. I made the screen look a little spi er by painting a black border around the image. Simply set up the projector to the correct size and dimensions, and then use a pencil to mark a border approximately 7cm around the projected image. Pay particular attention to the size and shape of the image — this permanent solution can be super annoying if you get the dimensions wrong. en simply paint the border using a matte black paint to give it that nishing edge. It’s important to use matte paint, as re ective paint will show glare and shine when the image inevitably comes into contact with it. If you want to get really serious, you can also paint the white area to improve the gain of the screen. Look for shades of colour that have absolutely no additives, which are usually referred to as the ‘base white’ colours. You won’t want a totally matte paint here, though, as it will lead to a at image quality. Most paints come in about ve
di erent levels of sheen — we suggest starting with the middle of the pack.
Another option is to use a light to medium grey paint for the main screen itself. ese are popular as they increase the perceived contrast ratio of the projected image, especially in rooms with less than perfect light control. is paint is not optimum for totally dark rooms, though, where white is the preferred choice, especially as today’s projectors have incredibly high contrast ratios.
SCREEN GOO
e next step up from using plain white paint is to use special paint designed for projector screens, with Screen Goo being the most well known. It’s not exactly cheap, at about $399 per 1,000mL tub, and comes in a variety of avours; reference white, high contrast, max contrast and ultra max contrast. Like paint, one of the beauties of Screen Goo is that it can be used on slightly curved walls, making for more of an immersive screen. Painting it on is as simple as using a short-haired bre roller, but the makers suggest spraying it as the ultimate method. A 500mL tub should cover around 2.33 square metres, but this drops slightly to 1.86 square metres when sprayed.
Screen Goo is an acrylic paint that is designed speci cally for projection surfaces, and is available in various levels of gain. According to the manufacturer, the lack of any ller gives it a far superior image quality than usual paint, using “museum-grade acrylic base resins and the best pigments available”. Other bene ts include exceptional colour delity, excellent gain with minimal hotspotting, industry-leading horizontal and vertical o -axis performance, wide viewing angles, zero colour shi ing and a colour accurate screen structure.
BUILDING YOUR OWN SCREEN
While painting a screen is arguably the cheapest method, nothing beats using proper projection material for your projector. Building your own screen and frame only requires a handful of tools, and can be done for around $600 including the cost of material. Let’s see how it’s done.
First things rst, determine the size you want, simply by projecting it on the wall. You’ll also need to pick the aspect ratio you’ll use most o en — 4:3, 16:9, 2:35:1. e most common aspect ratio for a Blu-ray screen is 16:9, though many movies now use 2.4:1.
Now to choose the material to use. You’ll want something sti enough that the screen doesn’t warp, which is where light gauge steel studs are handy. ey’re only a little more expensive than wood, but far more rigid. ey can also be easily cut with tin snips or a hacksaw, and are nice and light. Buy ve studs that are around three inches thick, and the right length for your height and width. You’ll want two vertical studs, but a third one to run through the centre of the screen to help keep it nice and rigid.
Now we need to assemble the main rectangular frame. Cut one edge of the stud so that the other piece can slide into place, and then use a rivet gun or bolt and screw to rmly a x each corner together. Next up is installing the centre brace — use the same method as you did to a x each corner to set this directly in the centre of the screen. is isn’t always necessary, though — if you feel like the frame is already sturdy, we’d avoid this, as it can lead to the central strut being visible through the projection material.
If you do go with the central strut, we’ll need to add some so padding across the entire front side to cover any spars or bolts. Very thin quilt stu ng will do the job nicely, so buy a piece slightly larger than the entire front space, and glue it over the front of the screen. Ensure you pull it extremely tightly as you do so, then trim o any spare overhang on the edges. You should end up with an extremely smooth surface devoid of any bolts or brace being visible, and this is what we’re going to stick our projection material to.
ere’s a wide array of di erent projection screen material on the market, all o ering di ering qualities — price, gain and colour. Go for a slightly greyish material if light is going to be an issue, while still with a gain of around 1.2 if your room is going to be dark. Go higher gain if light is a problem.
Buy a size that allows the material to wrap around the edges of the screen — not all the way so that it’s overhanging the rear, but so that it reaches the back edge of each screen edge. Now we’re going to buy some doublesided Velcro tape to keep it in place. Use one
piece per edge of the screen, giving the material something to affix to. Now place your material over the front of the screen, and slowly add the other side of the Velcro tape to each edge. As you do this, stick it to the screen, ensuring you pull it tight so that there are absolutely no wrinkles, and work your way around the edge of the screen. If you’ve done it right, you should end up with material in place that has no wrinkles.
However, the bene t of using double-sided Velcro tape is that you can pull it tighter in certain places if you notice wrinkles, which will also develop over time. Make especially certain that your corners are well placed with the Velcro in the right place, as this is where you’re most likely to get warping and rippling.
Our nishing touch is the black velvet used to outline the screen and provide a sharp edge to the image. We use black velvet as it absorbs any light — if your projection is slightly out of shape, the black velvet will make it impossible to see the error. Buy this in a long strip approximately 7cm thick, and then use more double sided Velcro to place it around the edge of the projector material.
Clean up any rough edges, and then you should have a screen that looks professionally made for a fraction of the cost.
Mounting it to the wall can be done in several ways. I’ve generally just used three or four screws, which the metal struts can just sit on, but some prefer a more rugged method.
It’s possible to screw a short (40cm) length of wood to the top strut, and then have a matching piece on the wall. e screen will then sit on this piece of wood — make sure you use a spirit level to ensure it’s nice and straight, otherwise you’re going to have an o -kilter screen.
e total cost of a screen like this is approximately $500, though it really does depend on the screen material you use, which can cost upwards of several thousand for the really serious stu .
One bene t this type of screen has over others is the use of the double-sided Velcro — screens do sag and wrinkle over time, but by using the Velcro, it’s incredibly simple to tighten up any so spots. It’s also perfect for building the perfect sized screen for your room, whereas most pre-built screens only come in select sizes.
Just remember to take your time, measure everything twice, and don’t get frustrated if things don’t go right straight away. Once it’s up and running, the joy of knowing you built this for a fraction of the cost of a pre-built projector screen will make the e ort more than worthwhile.