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Choosing a projector

For watching movies, looking at photos or any kind of planning, a projector is an unbeatable device that you won’t want to give up once you’ve tried it. However, the large screen and lower sharpness is not applicable for every job. With games, it’s about half that. If you use the projector a lot, you’ll stop wanting to work on the monitor. The reason will be your eyes. The projector is incredibly easier on the eyes than any glowing screen.

Before buying a home projector, you need to figure out its placement in the room and think about what you’re going to project onto.

Wall or canvas

A regular canvas is only 2-3m long. You can get a bigger canvas, but the price will skyrocket. Rolling canvas will come in small sizes. A flat wall that doesn’t restrict the size of the image and targeting isn’t that hard may be enough for you to project. Minor wall imperfections are not perceptible in the image. A white polar is sufficient, calibration has confirmed this. Unfortunately by projecting on a wall you lose some contrast.


Test where you will place the projector before you buy. The distance and image projection size calculator will help you do this. You can place the projector on the ceiling so that nothing interferes with the image. Before you start drilling, test carefully how far you need to place it to achieve the desired image size. Do not forget to use zoom of the projector when doing this. You’ll need to get two cables to the projector, a power and HDMI video cable. Installing the projector on the ceiling is very challenging, especially the cheap small bracket for low ceilings doesn’t allow for proper locking. But the ceiling is not the only place. Putting the projector on the floor is easier, but you need to adjust the seating. You split the seating and come up with a snack table, a shelf for stuff in between, and the projector in the space on the floor. This takes away the hassle of aiming, cabling and reduces noise. Remember that the projector down below will need to be able to blow warm air away.

You should have enough money to buy a home projector for 1000-2000 EUR. The choice is not difficult, you only need to think about three important features of projectors. The other features are just marketing bullshit.

1) ShortThrow

Hereafter referred to as ST, it stands for short-throw projection. If you have a small room, you’ve just severely limited your choices due to the small selection on the market. An ST projector can do up to twice the diagonal while maintaining the same distance. This is a great feature because even if you have a large room, a projector closer to the screen doesn’t need as strong a light and the light won’t be obstructed by your movement in the room. The ST has a minor drawback: its special lens won’t allow you to achieve perfect sharpness throughout the image easily (expect 1/3 of the image to be fainter).

Surely you know what a picture in a cinema looks like – it’s big! Why buy a projector and then limit yourself to a 3m screen. ShortThrow should be able to do from a ceiling to floor image like a cinema, so about 5m screen. The most important projector property that marketing prefers to hide, but you have to be able to find it in the technical details, is the optical property of the lens. How much it magnifies or reduces the image over a 1m distance. A standard lens is usually 1.2-1.4, so in simplified terms imagine that at 1m distance the image will be 20%-40% smaller. You make the image bigger by walking the projector from the screen to the other end of the room, and for a large image you will need to project from the neighbours :-). The best choice for cinema is the ShortThrow, which will have a 0.69-0.83 lens, so from 1m the image will be easily 30% bigger and from 3m you already have a 4m image and from 4m you get a 5m image from ceiling to floor. Beware of the Ultra ShortThrow projector, which has a 0.4 lens, but its placement is given right below the screen, so the size is usually limited to 2m, so you can buy a TV instead.

2) Resolution and frequency

I have a 4.5m image where even FullHD is less than one would like. Forget anything below HD resolution. Yes, DVD resolution is unwatchable! The difference between FullHD (1080p) and HD (720p) at such a large image is clearly visible, and for games, FullHD is the minimum. You will see the flaws of compression at low bitrates. You’ll spot fake FullHD movies right away – not everything on BluRay is truly FullHD. 4K (2160p) on monitors and TVs is commonplace, but manufacturers are slow to react again with projectors. What’s missing from the market are 4K ShortThrow projectors, without which you can’t create a big picture with a cinema-like experience.

Unfortunately, the refresh rate has remained the standard 60Hz, which is insufficient for the gaming community. There are indeed the first 120Hz projectors on the market suitable for gaming, but these are not ShortThrow projectors. I don’t know what kind of people buy a projector for gaming that will not allow to do real big picture.

3) Technology

3LCD yellow light from the main lamp is split through a dichroic filtering mirror. First you separate, for example, the red wavelength with one mirror, then the green wavelength with the other, and you are left with blue light. Each light is directed onto a different LCD. LCD for red, LCD for green and a third for blue. Each point on the LCD will either pass or not pass the light. Eventually, the three light images are combined again. The splitting of light and loss across each screen causes a loss of contrast compared to DLP technology. However, the refresh rate was dependent only on the LCD, so much simpler compared to DLP.

DLP and its rainbow effect is unique when the manufacturer uses a six-segment wheel (RGBRGB). You can only find out the type of wheel from detailed reviews, but for home cinema, (RGBRGB) must be used to ensure good colours. Other colours are put into the six-segment wheel, which can improve brightness, contrast and degrade colours. The image does not pass through the LCD, but through a screen made up of microscopic mirrors that rotate rapidly, thus either dropping the image onto the screen or off as a black pixel. It is not easy to increase the resolution and speed for DLP. 60Hz is 60 frames per second, so 60 times the rotation of the wheel, 120 times the projection of each colour and 360 times per second the rotation of the mirrors. For 3D the speed had to be increased to 120Hz (60Hz for each eye). However, 120Hz was initially only used for 3D and it was still a long time before the advent of gaming projectors.

What is a laser projector? The idea was to use three RGB laser lights instead of the main lamp, so that the light would not have to be split and there would be enough light for 3LCD technology. Using extra 3DLP can make the best and most expensive projector. But the laser is really expensive and it is worth using mainly blue. The middle option is to use two blue lasers, one for the blue light and the other is sent to the phosphor wheel to return the yellow, which the dichroic mirrors then make green and red. Finally, the light is processed by 3LCD technology. There are more combinations and the cost is moving towards the cheapest option of using just one blue laser with DLP processing.


The 3D display on the projector was no add-on, it was truly a 3D home theater. The new 3D ready projectors supported all 3D standards such as the most widely used side-by-side and interlaced. I recommend buying glasses directly from the manufacturer. You avoid synchronization problems and for example the Benq 3D uses a red spectrum color shift and the original glasses correct the shift perfectly. 3D glasses are expensive so it hurts that manufacturers don’t address convenience more and neglect polarizing filters. 3D on a projector has a big limitation with the older HDMI standard. While 720p ran at 60Hz, 1080p only ran at 30Hz, which limited the amount of games that were tolerable to play. The third dimension is completely immersive when playing and is the best you can experience yet. Unexpectedly, however, the biggest problem with 3D is with action movies. 25 frames for 3D is not enough, and projector manufacturers, unlike TV manufacturers, have completely ditched creating in-between frames for a smoother experience. But if you watch movies without fast scenes, you’ll feel like you’re in a movie theater already.


I have a Benq W1080ST DLP projector and the first thing that is very surprising is that even at this low price point, the colors are better than any monitor. Calibrating it, I found that the white balance was accurate from the factory. Unfortunately, the age of the projector lamp understandably changes the white balance. An inexpensive fix, if you are using a projector connected to a computer, is to calibrate the colors with a monitor probe to even out the colors. This is an anomaly that disappears with laser technology.


You know why noise is not addressed in cheaper models anyway? Behind a noiseless projector there is lower power (less consumption), worse luminosity, different segment wheel. In the end, less noise will be redeemed by the poorer image quality of a cheap projector. In the dark, a powerful projector has too strong a light. You can count on using the economical Eco mode and noticeably extend the lamp life. To get an idea of the real noise level, multiply the manufacturer’s stated noise by two. Note that the projector is always noisier on the ceiling above your head than when it is somewhere below you. Do you think the noise will be a nuisance? The most annoying thing about a projector is how much it heats your room. The measured power consumption of the Benq W1080ST is 280/210W in Eco mode.


Small integrated speakers are used to provide maximum sound for the presentation. In home cinema projectors, speakers make no sense at all. For movies and games, you’ll use headphones or large speakers that cover the projector noise sufficiently most of the time.


KeyStone allows image correction if you place the projector anywhere other than strictly horizontally opposite the center of the image and vertically up or down to the edge of the image. The use of optical correction in the case of vertical placement could perhaps be considered, but it is always a degradation of the image. Some take it as a minus when the projector doesn’t have it, but it’s actually a plus because it’s unnecessary. When you place the projector in a space in the room, everything else has to go. Because you can’t fake the image.

Think about

Do you know how well a graphics card can heat a room? So together with a projector you can heat the whole apartment 🙂