true match coollights combo

[J Davis]

anyone shooting with a coollights and true match combo?
do you see a cast or is it the same as when in a kino?

 

[Bern Caughey]

I've only compared the CDM-150's daylight output to Diva 400's. The Coollight's is warmer, & if I remember correctly, more magenta. I tried various gels but never matched them exactly.

Even with the help of a Color Meter matching different types of lamps is often tricky, especially discontinuous sources.

 

[J Davis]

hi bern, I meant the true match bulbs as in the ones made by kino but place in the coollights flo unit
I know logically the light should be the same as a kino but my mind might be playing tricks on me and seeing a cast

 

[J Davis]

I looked up the documentation provided by kino and they do say somewhere if the true match flo bulb is dimmed it gets a
magenta cast but
I don't know much about volts - watts -amps relationship so I'm guessing that maybe the coollights flo powering a true match bulb
might be similar to a slightly dimmed kino. (very wild guess)

 

[Bruce Watson]

anyone shooting with a coollights and true match combo?
do you see a cast or is it the same as when in a kino?

I remember seeing something about this a few years ago. Might have been on this forum, IDK. Bottom line, the Kino bulbs in a Cool Lights fixture should give the same quality of light as if using a Kino fixture. But... it's a (very) small change that's perhaps not worth the effort or cost.

What I remember is that the Kino true-match bulbs are pushed a little more toward film capture. Film is more sensitive to color than video, so the Kino bulbs have a little higher CRI, at the expense of a little less lumen output.

The bulbs Cool Lights uses are pushed more towards video capture. They make the opposite trade off -- more lumens for a slightly lower CRI.

But don't get too hung up on CRI -- every time I watch a basketball game on HDTV, lit by huge stadium HMIs with a CRI in the mid-80s maybe, but giving excellent results, I'm reminded that CRI isn't everything.

 

[ian dart]

i have been using kino tubes in richards cl455p lights for the last several years without any problem.
the main reasons i use them is: they are easily available, they are a known quality, and when i tell the dp i can
give him a 4 banker he knows what to expect light wise.

although mine are non dimmable i have noticed on the diva that they do have a slight magenta shift when dimmed.

cheers

 

[J Davis]

i have been using kino tubes in richards cl455p lights for the last several years without any problem.
the main reasons i use them is: they are easily available, they are a known quality, and when i tell the dp i can
give him a 4 banker he knows what to expect light wise.

although mine are non dimmable i have noticed on the diva that they do have a slight magenta shift when dimmed.

cheers

when you put the bulbs on the cl455p, does it look like when they are on the diva slightly dimmed?

 

[ian dart]

i have had the coolights and keno on in the same setup and and cannot see any difference in brightness.

there is probably an expectation that at four times the price that the keno would be brighter but i have never noticed this.

i do tend to only use them with lee 250 or quarter grid to soften them up and as a mid to close up light.
if i need something with more throw i go with the 4ft 4 bank kenos.

as a freelance gaffer it is important that my lights are similar to the industry standard so the dp can make an informed
decision based on his previous experience.

cheers

 

[J Davis]

i have had the coolights and keno on in the same setup and and cannot see any difference in brightness.

Thanks for writing back Ian. What about color shift? Do you see a slight magenta cast when the same bulb is in the coollight fixture?

 

[ian dart]

i have not seen color shift in undimmed fixtures.
i have the non dimming coollight fixtures and am more than happy with the keno tubes in them.
if i need to knock back the level i turn off tubes, move them back or use nd.
i have seen a slight magenta shift in diva's when dimmed and i assume it is barely noticable on camera when used
with other lighting in a scene because no dp's have asked me about it.

cheers

 

[J Davis]

...in undimmed fixtures.

that might be it !
there might be a difference in voltage between a dimable coollight on max brightness and a non dimable coollight. This voltage difference might explain the magenta cast that I think I can see. I have a dimable coollight and a non-dimable coollight .... will run some tests when i next have testing time

 

[ian dart]

well theres the problem....

theoretically there should be no difference if both models are at max output and the tubes are the same make.

perhaps richard can let us know. i have found him most helpful when requesting information.

what type of tubes are you using ? i have only noticed the shift if dimmed below aprox 50%.

ahhhhh life was so much easier in the old days when you only had incandescent or hmi.

cheers

 

[J Davis]

just ran a test -
top is a non dimmable coollights 4 bank loaded with only two true match bulbs
bottom is a dimmable coollights 2 bank loaded with the same two bulbs and the dial on max
edit: same camera, same lens yada yada ...