Tcp Compact Fluorescents

[Anna Uio]

Hi all,

 

Anybody have any experience using Tcp compact fluorescents as light sources? I saw some Par30 4100K in a shop window a liked the color and light, so I asked the owner what they were. On the web I then saw they have a variety of color temperatures.

 

Cheers,

Anna

[Guest Patrick Nuse]

Hi all,

 

Anybody have any experience using Tcp compact fluorescents as light sources? I saw some Par30 4100K in a shop window a liked the color and light, so I asked the owner what they were. On the web I then saw they have a variety of color temperatures.

 

Cheers,

Anna

 

I took some digital stills using a compact flourescent. It is 5500K and 27W about 100W incandescent equivalent. The rendering is surprisingly good. This was just a "daylight" bulb from Home Depot. B&H photo sells fixtures with fluorescents of much higher wattages.

The biggest Ive seen is 105W which is equivalent to about a 500W halogen. I imagine they would look equally great for video.

[John Crow]

Good question. Does anybody know if flicker or color spikes are a problem with those, as they are with regular, non-Kino flourescents? I've never used one to light a scene, every time I've run into them they had to be removed anyway b/c we were using dimmers. And as long as we're on the subject, I've never really totally understood why Flourescents and HMIs go all crazy when you put them on dimmers. I'm sure it must have something to do with the voltage drop. Can anybody answer that more thoroughly?

[John Baustian]

And as long as we're on the subject, I've never really totally understood why Flourescents and HMIs go all crazy when you put them on dimmers. I'm sure it must have something to do with the voltage drop. Can anybody answer that more thoroughly?

 

 

I'll give it a try.

 

HMIs and flourescents both convert electricity into light by the same basic principle, that of passing an electrical current through an ionized gas. The key word is ionized. Keeping the gas ionized requires maintaining the applied voltage within a particular range, while controlling the current. (Too much current can damage the lamp.) Dimming these lamps requires some specialized electronics, which is beyond the capability of most dimmers used for tungsten lamps.

[Walter Graff]

Good question. Does anybody know if flicker or color spikes are a problem with those, as they are with regular, non-Kino flourescents? I've never used one to light a scene, every time I've run into them they had to be removed anyway b/c we were using dimmers. And as long as we're on the subject, I've never really totally understood why Flourescents and HMIs go all crazy when you put them on dimmers. I'm sure it must have something to do with the voltage drop. Can anybody answer that more thoroughly?

 

Dimmers don't change voltage, only cut the wave. Flouros and transformers can't be dimmed properly by cutting the wave and rather need changes in actual voltage.