vidwerk wrote:Just came back from home depot. They have 24" GE "Daylight" tubes rated at a CRI of 92. I also saw plug-in(non hard wired) fixtures for them that claimed to be low-hum/flicker-free. Are these flicker free for motion picture use? I imagine not. The total for both the tube and fixture is about $40. CDN.
vidwerk.
I was checking that out a few weeks ago. Bulbs seem pretty good, and you can even buy plastic housing for the bulbs so they won't shatter everywhere.
I'm also curious if there will be flicker issues. I guess it is also dependent upon the camera you are using. The 1014's 150/220 shutter angle will have different safe speeds than using the 4008's 1/90th or 1/45th shutter speeds.
I'll probably pick one up and give it a test.
BTW - Nice avatar. Cracked me up.
vidwerk wrote:...I also saw plug-in(non hard wired) fixtures for them that claimed to be low-hum/flicker-free. Are these flicker free for motion picture use? ....
The fixtures are likely similar to what is done in compact fluorescent bulbs. The AC is full wave rectified and filtered to DC, and an oscillator drives the tube at a high (ultrasonic) frequency with some sort of current limiting. This eliminates the heavy and expensive line frequency ballast.
There is likely still some 120 Hz flicker owing to incomplete filtering of the rectified AC, but much less than with a regular ballast. So you might be able to get away with filming at the "wrong" speed or shutter opening.
vidwerk wrote:...I also saw plug-in(non hard wired) fixtures for them that claimed to be low-hum/flicker-free. Are these flicker free for motion picture use? ....
The fixtures are likely similar to what is done in compact fluorescent bulbs. The AC is full wave rectified and filtered to DC, and an oscillator drives the tube at a high (ultrasonic) frequency with some sort of current limiting. This eliminates the heavy and expensive line frequency ballast.
There is likely still some 120 Hz flicker owing to incomplete filtering of the rectified AC, but much less than with a regular ballast. So you might be able to get away with filming at the "wrong" speed or shutter opening.
