That depends on a number of factors, including how much power you're running, how brightly lit the room is, how close you are to the wall, how far away from the projector the wall is, and how smooth or rough the wall is.
As a general rule, a 1 watt projector is going to be OK to view at a distance of 15 ft or greater, assuming the projector is an equal distance away, and assuming that the wall is painted with a flat (not gloss or semi-gloss) paint. More light in the room will increase the safety margin (your pupils will constrict, allowing less light to enter).
Bottom line: if it seems too bright to your eyes, if you find yourself having to squint or shield your eyes, or if you get a headache from watching it, then reduce the output power of the projector or increase your distance from the wall.
If you see after-images, it's definitely too bright!
It's rare to suffer permanent damage to the eye from a diffuse reflection off a wall, even at power levels of 1 watt. However, it's not unheard of. So be careful. And make *sure* there are no reflective surfaces on the wall. (Watch out for things like picture frames, windows, metal light fixtures, etc.)
That *should* be OK, but you may want to reduce your projector's power output when running it on your desk just to be sure. (See if your controller has a beam attenuation map or master brightness control in software to do this.)
Worst case, set it up with the room lights on first, and see how it looks. Then turn the lights off. If it suddenly becomes too bright to look at with the lights off, you know you'll need to turn the power down.
Adam
Originally Posted by buffo
That depends on a number of factors, including how much power you're running, how brightly lit the room is, how close you are to the wall, how far away from the projector the wall is, and how smooth or rough the wall is.
Reply With Quote
