Although a good screen could optimize the viewing experience, it's not necessarily required when you use a projector. For those who don't require a high-quality or expensive screen for their projectors, we know a clean surface like a flat white wall is quite enough. In another way, a good projector is always important. In this article, we don’t discuss the different picture performances with a screen or without a screen but we’ll only talk about projection without a screen, ie, with only a wall.
Is a flat white wall as perfect as you saw?
Take a close look at your wall to find if there are smudges or unevenness, which almost everyone will do to check if your wall is good for a projector to project on. However, it’s not always accurate. Run your hands across the surface of the wall and you will actually feel if it's really flat or not.
An uneven wall may cause projection image distortion
In order to prove that an uneven wall may cause distortion from a projection, we did a test to project the CASIRIS A6 projector from an uneven wall to a flat surface(a flat screen and a flat white wall).
When it’s projected on an uneven wall, the image is distorted with curved lines. The 8-point correction will not work this way even if the 8 points are adjusted to the right positions. This is because the unevenness of the wall hinders the normal path of light. The wall we use to project on looks flat but it’s actually not. So we try to move the projector to the CASIRIS Aura Screen and a flat white wall in another room, and both of them work perfectly.
Check out the test video and the comparison images:
1. In order to get the best viewing experience, make sure the wall to be the projection surface is a flat white wall.
2. Mark the uneven part and smoothen it using sandpaper or a power sander.
3. If possible, paint the wall with projector screen paint.