Q. Like in a commercial building. Can you buy battery powered commercial lighting thats not connected to a 120volt plug? and what activates emergency lighting?
i figured, that the emergency lights would have to be connected to a 120 power supply from the building to be activated when power is cut. i just dont see how these emergency lights are triggered. unless they are connected to the buildings power?
i figured, that the emergency lights would have to be connected to a 120 power supply from the building to be activated when power is cut. i just dont see how these emergency lights are triggered. unless they are connected to the buildings power?
A. Emergency lighting is always connected to the AC power, both to keep the batteries charged and to detect when to turn on.
If it were not connected to the AC power, how would you charge the batteries?
To repeat, the system is triggered by the AC power going to 0, probably by something as simple as a relay across the AC power leads.
If it were not connected to the AC power, how would you charge the batteries?
To repeat, the system is triggered by the AC power going to 0, probably by something as simple as a relay across the AC power leads.
Anyone know anyone who buys unused commercial light fixtures in California?
Q. Im looking for anyone to buy some unused commercial light fixtures that we have left over from a completed job. Does anyone have any ideas?
A. the surplus house
How do they make the commercial with light pictures?
Q. It's a commercial for a printer or camera or something, and it has people making shapes with glow sticks or sparklers in the dark. How do they make it?
A. It's called light painting. Those commercials are lots of individual shots put together.
Light painting is done with a long exposure in minimal light. Or no light. While the photo is being exposed, the person "writes" in the air with a glowstick or a pen-light. The exposure usually goes on long before or after the person has done the writing, so they often don't appear at all as the scene exposes without them in it.
If doing it in no light at all, fire a flash after you're done to expose the rest of the scene.
Light painting is done with a long exposure in minimal light. Or no light. While the photo is being exposed, the person "writes" in the air with a glowstick or a pen-light. The exposure usually goes on long before or after the person has done the writing, so they often don't appear at all as the scene exposes without them in it.
If doing it in no light at all, fire a flash after you're done to expose the rest of the scene.
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