Projector Projection Screens
If you are buying a projector you at some stage will need to know about what projection screens are and what they can do for the quality of your final picture. you will need to consider factors such as:
- how large the screen should be, should it be a grey or white screen,
- if the projection screen should be grey or white,
- motorised or not, and
- aspect ratio, 16:9 or 4:3 or even square (1:1).
This article discusses some of these factors.
Why buy a projector screen?
Buying a projection screen will add to the expense of your projector purchase but you will need to consider what you will be compromising. Why isn't a plain white wall good enough? Projection screens use a special optical reflective coating to maximise picture quality. If you use a plain white wall, you will be losing contrast, sharpness and brightness. In summary your projected picture will not be as great as your projector is capable of. Another point worth considering is the longevity of a projection screen. A projection screen can outlive a projector many times over, and may even last a lifetime if it is high quality!
Finally, some projection screens have black borders. The human eyes colour perception is influenced by what colours surround the image that is viewed. Screens with black borders seem to show nicer images, and colours!
16:9 or 4:4 or square?
What aspect ratio you chose will likely be a personal preference. If you have a 4:3 projector, you may consider purchasing a larger projection screen so you can display adequately sized 16:9 images with appropriate masking. Similarly, you may consider buying a larger 16:9 projection screen, for a 16:9 projector to display adequately sized 4:3 images with appropriate masking. If you have a 16:9 projector and you will not be displaying any 4:3 content, then you may be happy with a smaller 16:9 screen. The size of the screen will depend on how big you want your projection for any particular aspect ratio.
Figure 1: 2.25 aspect projection on a 1.77 aspect screen.
Figure 2: 1.33 aspect projection on a 1.77 aspect screen.
How large should the screen be?
This will largely subjective. For example, those who like sitting in the front row at the movies will want a large projection. Those who prefer to sit near the back will likely prefer a smaller projection. The size of the desired projection will determine the size of the projection screen. You may want to give yourself space by buying a slightly larger screen to handle the different aspect ratio's of display material. Points to think about are
- If the projection is too big, you may feel spatially disorientated causing a less desirable viewing experience.
- The larger the projection and the closer you sit, the more noticeable the projection artifacts are.
The so how far should you sit to minimise artifacts. As a guide, try 2 times the width of the screen away. Any closer an you may start noticing artifacts or feel overwhelmed by the image.
Grey or white screen?
If you have a projector with lower contrast but higher brightness levels, you may consider a grey projection screen.
These screens are specially coated to improve contrast levels. This is NOT the same as using a grey painted wall! Indeed, a white wall is better than a grey wall!
Motorised projection screen?
Projection screens can be manual pull down, motorised or just fixed to a wall. Your selection will probably be limited to your budget. Most chose the pull down variety, allowing the projection screen to neatly hide away. If your budget allows, you may consider a motorised screen. These screens can be hidden away in the wall.
Buying a projection screen should be considered when purchasing a projector. Projection screens maximise the projectors capability with respect to contrast, brightness and sharpness levels. A buyer should consider purchasing a 16:9 or 4:3 aspect ratio screen depending on the material to be displayed. Buyer should consider buying slightly larger screens than the typical desired projection size. This allows for larger projections across the different aspect ratios. The size of the projected image is subjective, but be aware of the limitations in having the projection image too large. For example, the appearance of artifacts and being overwhelmed by the image. Grey coated screens exist for projectors that have lower contrast ratios, however there is no substitute for a projector with a good contrast ratio. Projection screens can be motorised or manual. Your selection will depend on your budget and taste.