A complete installation


Even the largest flat screen TV does not give a cinema-like impression except in small rooms or if you sit close. Be warned! Once you have used a projector you will find even 60 inch TVs too small. Fortunately projectors are now quite cheap. However the range of choice can be mind-boggling and it's easy to choose the wrong one. This is what I have discovered.


There are two types; LCD (liquid crystal display) and DLP (which uses an array of tiny mirrors). For TV and cinema it is best to have one with three LCDs (3LCD), one for each colour. The contrast is poorer than DLP, but you don't get the coloured fringes in fast moving pictures that happen with DLP, called the 'rainbow effect'. LCD projectors are larger but that is not a problem for a permanent installation.

Choose a projector that has lens shift controls that can physically move the image vertically and horizontally without tilting or turning the projector. Your projector is unlikely to be perfectly lined up with your screen and using electronic adjustments such as 'keystone' will reduce picture quality.

If you are planning to use an electric screen, it is best to buy a projector and a screen that allows the projector to lower the screen automatically when it is switched on.


This is a tricky one. The first projector I used produced 1200 lumens. Even on a 2.3 m screen this was fine for brightness. If you cannot blacken your room, or need an even bigger image, then you will need a higher brightness rating. It is best to blacken the room because if there is any light in the room you cannot get true black on a white screen.

I have recently been trying a new high-definition projector, the Epson TW3500, with 1800 lumens, 1080p and contrast ratio of 36000 to 1. First impressions are very good. The quality of the picture is excellent even at 2.3 metres wide. 1080i, on BBC HD from freesat, is very clear and the brightness is good enough for a fairly bright room if you use the dynamic setting. I have used up to 10 metre HDMI connections with it. The cables I use are ordinary quality, not high-priced ones. So far they have worked fine. The remote is good, with separate buttons for the most-used functions, including a separate one for each input - HDMI1, HDMI2, Component, VGA etc. I am going to recommend this projector.


This takes some thought and planning. If you want to install the projector permanently it is probably best to ceiling mount it if you have the height, or rear wall mount it if not. The ideal position is where it is exactly central to the screen both vertically and horizontally. However this is usually not possible, so you will need to shift the position of the picture. Remember that the lens is not normally in the centre of the projector. I forgot this when I positioned one ceiling mount, which was beautifully lined up with the centre of the screen. So, of course, the lens was offset a bit. Obviously I moved it using lens shift. Make sure that the projector you buy has enough lens shift adjustment (see 'Type' above). This is different from keystone correction as you will see later.

The higher or lower it is, or the more it is displaced sideways, in relation to the centre of the screen, the more the picture must be moved. Movement using the lens shift adjustments might reduce picture quality, but not usually noticeably.

One important thing that is not usually mentioned is the centre of mass of the projector, also known as centre of gravity. If this is not exactly below the centre line of the mount there will be forces on the projector that will gradually tilt it. I have never seen the centre of mass shown in a manual, so you will need to find it for yourself. You need a triangular or round bar slightly longer than the longest dimension of the projector. Put the projector on top of the bar so you can see both ends and move it until it is balanced. Mark the position of the bar in some way. Do this again with the bar at right angle to its first position. Mark again. Where the lines cross is the centre of mass. It would be worth putting a small permanent mark in case you need to re-install.

You must make sure the projector is aiming dead level, not tilted up or down. This is not easy. Projectors ought to have a spirit level built into them! Make sure the mount is vertical and the projector is at right angles to it. If the projector is flat on top, you can put a spirit level on it to get it level. If it is curved then tilt the projector until the edges are exactly parallel. You can use the screen edges as a guide. Why is this important? In this position the picture has no 'keystone' distortion. This where the picture gets narrower from top to bottom, like the keystone at the top of a stone arch, or from side to side. Once you are sure it is correct then check that the top and bottom edges are parallel, swivelling the projector from side to side until they are. It might take a bit of fiddling to get all four sides correct. Finally use the lens shift adjustment to move the picture up or down, or to one side, to get it central on the screen. Some projectors have a 'Pattern' button, which projects rectangles and circles to help you. Do not use the 'keystone correction' on the projector. This will always reduce the quality because it moves pixels within the picture.

You will also need to ensure that you can get an image that fills the screen. Projectors can zoom to change picture size. It is best to spend some time experimenting with the projector and screen to get the best combination of height and distance before you decide where to put everything. Projector makers' sites often have an online calculator for picture size and distance.

Two warnings

One problem with projectors is the cost of the replacement lamps. If you buy a lamp made by the original manufacturer it is likely to cost a hundred pounds or more. However if you note the number and then search on eBay, you might well find one at about twenty pounds. There will be a delay as the supplier is likely to be in the Far East, so buy before you need it and get two while you are at it. You can usually check the elapsed hours on your projector using the menu. Replacing the lamp is usually very simple.

You should clean the projector regularly. Follow the manual scrupulously. There will be at least one filter which should be banged clean at least once a year. The frequency will depend on the dust level in your house. In the end the filter will need replacing. You will know when, because your projector will shut down due to the lamp overheating. Filters cost more than the cheap lamps.

Cables and wires

You will need to provide power and signal wires to the projector. If you want to sink these in the walls this is a major job, described on another page. Alternatively you can buy quite attractive surface trunking at TLC. Be aware that if you do other than minor work to the permanent mains wiring you might need it inspected under part P of the new Building Regulations. The nanny state assumes that you are an incompetent imbecile too stupid to avoid harming yourself. You should also keep mains and signal cables as far apart as you can and they should cross at right-angles if possible.

There are very many ways of connecting, which are discussed elsewhere in this document. If you can, go for component video connections or HDMI. You can use HDMI up to 10 or even 15 metres, but for longer connections you will need either an inline HDMI amplifier or use component. Both component and HDMI will allow you to watch high definition up to 1080i, though for 1080p only HDMI will work.

You might have several pieces of equipment to connect, for example a sound system, video cassette recorder, freesat tuner and recorder, and DVD recorder. The main problem is the wires. You can't get wires short enough to connect equipment in a stack. 0.5 metres is usually the shortest. This means a revolting tangle of overly long wires. I have taken to making up shorter ones where I can, for example phono wires for component video and mains wires. It's still a mess though.

SCART sockets are inflexible because they do not seem to be isolated from each other in most equipment. This means that if I wire up so that a piece of equipment is connected to the AV1 socket on a TV for playback and also to a DVD player/recorder, and then I connect the DVD player to AV2 on the TV, there is loop and problems occur. You have to use a switching box to overcome this.

In the near future many of the connections problems will probably disappear. Belkin has launched a wireless connection, called Flywire. This has a transmitter that can take HDMI, SCART, S-video and component signals and send them to a receiver near the television or projector which will input to an HDMI socket. This will be particularly useful for wall or ceiling mounted projectors. This system is expensive, but devices will of course get cheaper, especially when the receivers are built into equipment.

HDMI is a special case and has a whole page devoted to it.


Screens can be ceiling or wall mounted or put on a tripod. The last is not a good idea if you have children! A white painted wall may be used, but you will lose some brightness as the screen material is reflective.Screens can be manually pulled down or electrically operated. Manual ones are fine, but it is a fiddle to get the position exactly right. Some projectors now come with a socket that allows them to lower an electric screen that also has this facility.



(C) Peter Scott 2009

Last edit 1 February 2017