Not sure if this is a new phenomenon, there seems to be an increase in advice requests for projector setups in ambient light. With lights on, windows open, etc.
Most are looking at their first projector in the sub 2K$ if not sub 1K$ range.
Essentially a big TV.
This is probably the result of price drops in the budget projector market, and increases in TV diagonals. The new UST's (from an aesthetic angle) with those highly viewed videos of UST + ALR combinations are also responsible.
It gives people the impression that a large screen can be had in medium or even high ambient light conditions. If the image were to be inspected, it's not all as it would seem. The bright parts of the projected image have better visibility than the dark, but with too much ambient light both will be washed out.
This is not the environment projectors were originally made for. A dark room, with darkened walls, not an excessively bright screen, in other words a cinema hall. Even with lumens having increased over time the task of using a projector in a ambient light environment is a challenging one.
In low ambient light, a grey screen will absorb some of the light bouncing around, and will keep the image from being washed out.
Originally Posted by bud16415
Here is an example done years ago by a member. It is a side by side comparing a mild neutral gray to a white. The samples were painted one with a flat white paint the other with a flat neutral gray in around the .7-.8 gain range.
One photo is taken with a dark theater setting and the other had some ambient light turned on in the room.
Draw your own conclusions there were no trick settings to the camera and I believe the poster to be honest and he said the photo closely showed what his eyes saw.
With more ambient light, the image would be even more washed out.
Even with an ALR screen, if there is too much light the screen will not be able to help. Increasing the lumens would also do little. Strategic placement of lights so they don't hit the screen directly and not too much light will improve a setup with ambient light.
More info on ALR screens here:
To illustrate how ambient light affects PQ I placed two white A4 sheets on the center of the screen (ALR Cinegrey 3D). Room with white walls, projector puts out ~800 lumens in this configuration. Screen is rated at 1.2 gain, probably it's 1.0 or less. No light is coming from the direction of the projector.
The four scenarios are, from left to right:
1. Lights off, blackout curtains on.
2. Lights off, blackout curtains off, transparent (orange tinted) curtain on. An orange tint can be seen in the second picture.
3. Lights off, all curtains off, with two windows open, in daytime. One window is just the right of the screen (3m/9ft), the other one is at a 45 degree angle (5m/15ft).
4. Curtains on, one light on at 1.5m/5ft from the screen. It directly hits the screen. A yellow spot can be seen in the upper center of the screen.
The result is as described above. The bright parts of the image are better off, the dark parts are seriously washed out.
More examples with this setup:
There are plenty of pictures and videos of ambient light setups available online.
Note: also tested vs a white screen and a Cinegrey matte screen, rated at 1.0, but probably lower, with the same setup. Also had a sampe of a paint mix, the Black Widow Grey pearl.
The Cinegrey 3D increased the saturation of the colors vs the white and especially the grey screen.
The grey screen was washed out with desaturated colors, but with better black level. PJ brightness was about 20fL.
Black level was best on the Cinegrey matte>Cinegrey 3D>white screen.
The BL GP was almost identical to the Cinegrey 3D in the dark, but with lights on it behaved similar to a matte surface, i.e. washed out.
When the lamp was at around 3500h with ~15fL the Cinegrey 3D was bright enough in medium to medium-high ambient light conditions.
More shots with the same setup:
LE2: A review of Carl's ALR with an Epson 6040UB at unknown distance. The pictures projected are very bright so it's unclear if there is a hotspot, but from the pictures one cannot be discerned: