halogen to daylight filter? gel?

[Joe G.]

Homies,

I learned that halogen lights are about CRI 100, which is exceptionally good. Unfortunately they are only 3000 to 3400K, which is relatively bad considering the Red sensor.

Is there a quick and easy way to shift the light temp? Since they are very hot, a plastic gel would just melt. Are there glass filters in the blue range to do this? I suppose a slight bluish tint would do the job, and it wouldn't need to be exact.

Any thoughts?

 

[donatello b]

"which is relatively bad considering the Red sensor."

IMO (based on build 15) normal tungsten scenes are fine using RED ... it is true you get a cleaner blue channel using daylight but tungsten works ... i would keep all lights above 2800Kelvin ..
do a test using tungsten and then take it thru post to CC and see if you like the results ...

 

[Yannick Hagman]

I have dichronic daylight filters on my dedolights, you lose 1 f-stop. So the output is 300w instead of 600w (non-halogen thungsten). Half light power. Glass CTB-filters lose 2 f-stops (150w non-halogen thungsten on my dedos)

 

[Dylan Reeve]

There are heavier gels available, I have used them in the past with 500W halogen flood lights. They worked well.

I've also used normal CTB gel with the same lights - it melted when too close but with a little space between the light face and the gels it was okay.

 

[Joe G.]

tiffen?

tiffen?

What about throwing on a Tiffen 80A or 80B, and using the lights as-is?

What's the specific difference between a and b?

*** I found what I'm looking for: a filter that is 3/4 blue c.t.b. Unfortunately, I can only find it in gels, and not as a glass lense filter. Is there a manufacturer that makes a filter in 3/4 blue?

 

[Joe G.]

Well, I got the answer to the Tiffen question from Tiffen:

"The 80A will balance daylight film to 3200 degree Kelvin lights and the
80B to 3400 degree Kelvin lights."

Harold E. (Harry) Hofmann
Senior Technical & Customer Service Rep.
Tiffen Acquistion LLC

That would appear to mean that 80B is the way to go, as we want 5000K, not 5500k. The 80A is more like full blue, and the 80b is more like 85% blue (by my calculation).