Welcome to our community

Be a part of something great, join today!

Log in
  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Balancing Practicals to 5000-5600K

I Bloom

I Bloom

Well-known member
Joined
Jan 5, 2007
Messages
2,195
Reaction score
0
Points
0
Location
USA
Website
www.ianbloom.com
I'm shooting a film with several night interiors. I'm going to be motivating everything with practicals. Aside from photofloods what is the best way to shift incandescent bulbs to daylight.

IBloom
 
David,

Have you used these? Do they need any correction to balance with HMI's? Are they dimmable?

Seems like it would be better to use 100w incandescent that has a permanent CTB filter in place of 20w

Ian
 
Have used some daylight high CRI CFL's in chinese lanterns to light my wife's art studio. They match well with the natural north light from her studio window and render pigment colors very well. We have photographed her paintings with a Nikon D40 under these. They seem to go a little to the red rather than green on the Nikon. Easy to color grade them in photoshop. Shouldn't need to correct for use with HMI's.
There was another site I have run across before that had photographic quality CFL's in a variety of color temps: 3000, 4500, 5500 6500. I'll see if I can find that again.
They are sort of dimmable with dimmers rated for fluorescent use but dimming can cause flicker problems.
 
I haven't used them yet. True, you could gel a tungsten, but I thought we were talking about light bulbs inside of practicals, which are near impossible to gel, so that leaves blue-painted photofloods... but you were asking for alternatives to that. Were you asking for tungsten alternatives? Because there aren't any other than the blue bulbs. There are dichroic PAR's, but those don't go into practicals.

Generally a CFL is not dimmable.

I suppose the alternative would be to build a lamp around a Joker 200 bug lite or something. That would get expensive...

I don't suppose anyone has crammed daylight LED's into a lightbulb housing yet?

I've thought about the daylight CFL idea though for putting into Chinese Lanterns for a soft moonlight effect outside at night.

Unfortunately, having to turn tungsten practicals into daylight tends to be a RED issue because normally you don't want tungsten practicals to be 5500K. I've rarely had to consider doing it on any large scale until the RED camera came along. If I had a tungsten practical come on during a daytime scene, I generally wanted the difference in color temperature. And if I were shooting a night interior scene, there was no problem working with a 3200K balance. So on the rare occasions when I thought a tungsten practical was too orange in a day interior, I used the blue-dipped photofloods, which are around 4800K.
 
stupid question.

What does HMI stand for and are all HMI's daylight temp?
 
Havn't used Practicals yet...
What bulbs can I use in standart fixtures and how bright and in what Kelvins can I get them? Do I have to prepare or have special Practicals when using high wattage bulbs? How long do those live? Are they expansive?
 
Kim Frank said:
Havn't used Practicals yet...
What bulbs can I use in standart fixtures and how bright and in what Kelvins can I get them? Do I have to prepare or have special Practicals when using high wattage bulbs? How long do those live? Are they expansive?
Click to expand...

"Practical" is just a nickname for light fixtures that are seen on-camera, like a desk lamp, floor lamp, worklight, whatever. And these household and office fixtures use all sorts of bulbs, some are tungsten, some are fluorescent, etc. The fluorescent ones are generally easy to switch to daylight-balanced tubes.

You can switch ordinary tungsten lightbulbs to daylight compact flourescent bulbs, the main issue being how much green they have mixed into them, how good their CRI rating is.
http://en.wikipedia.org/wiki/Color_rendering_index

In terms of how high a wattage bulb you can put into a fixture, is just depends. Most plastic sockets say to not use anything higher than 60w in them, but how many people listen to that warning? You can put higher wattage bulbs in, but if you leave them on for too long, there is an overheating, melting, and fire hazard. I've used 250w "213" bulbs in ordinary table lamps, for example, but it does get hot. I've even managed to get away with 500w photofloods, but only for brief periods. If you are using a paper Chinese Lantern for lighting scenes, for example, it's a good idea to get rid of the ordinary plastic socket and get a porcelain socket from a hardware store, perhaps with a heavier gauge wire while you're at it.

One advantage to fluorescents, including compact flos, is that they are generally much lower in wattage compared to tungsten lightbulbs of the same brightness.
 
And if you would need to use high wattage bulbs (do you?) would yor gaffer prep the Practicals as well by changing the socket?
In Terms of Chinese Laterns:
Do you use the normal paper ones, wouldn't they have a slight warm colour shift, or are there some with Frost?
 
David Mullen ASC said:
I haven't used them yet. True, you could gel a tungsten, but I thought we were talking about light bulbs inside of practicals, which are near impossible to gel, so that leaves blue-painted photofloods... but you were asking for alternatives to that. Were you asking for tungsten alternatives?
Click to expand...

Well, I don't trust CRI's yes because of the green content. If they don't get the proper wattage I think they are likely to shift.

Photofloods are too bright and they burn out after two hours. I guess the ideal is a 100W bulb painted CTB.

IBloom
 
I Bloom said:
Well, I don't trust CRI's yes because of the green content. If they don't get the proper wattage I think they are likely to shift.

Photofloods are too bright and they burn out after two hours. I guess the ideal is a 100W bulb painted CTB.

IBloom
Click to expand...

Blue dipped 100w and 60w globes exist - I'll ask my gaffer what they are called and where they come from. We were using them the other day.

You could also try these grow lights ....

http://www.filmtools.com/60wdabufe.html

Matt Uhry
www.mattuhry.com
 
Yes, I've seen lower-wattage blue-dipped bulbs too (maybe it was over at FilmTools or Moletown), I just never have much use for them because once you paint a 250w bulb blue, it's already more like a 60w bulb in brightness.

I think Rosco makes a paint for bulbs.
 
Kim Frank said:
And if you would need to use high wattage bulbs (do you?) would yor gaffer prep the Practicals as well by changing the socket?
In Terms of Chinese Laterns:
Do you use the normal paper ones, wouldn't they have a slight warm colour shift, or are there some with Frost?
Click to expand...

Just depends. Most of the time, I just put the brighter bulb in the practical and make sure to turn it off between takes.

Yes, I use the normal paper lanterns. Usually they are not as warm as the household practicals in the room so I have to put a brighter bulb in the Chinese lantern and then dim it down to warm it up.
 
I Bloom said:
Promising:
http://www.filmtools.com/bca250wattge.html

I'll post some stills if I shoot with these. Should I expect the output to be closer to a 60w tungsten?

IBloom
Click to expand...

Yes, 60w to 75w. Think of it this way, the amount of blue gel needed to convert a tungsten light to daylight loses nearly two-stops of light. So half of 250w would be 125w, and half of that would be 62.5w... hence why the output is in the 60w to 75w range.
 
David, thank for taking the time to shed some light. I have a few questions that I can't seem to find any answers to:

1. For an interior daytime scene, what color temp for the practical bulbs are best? I assumed that blue daylight photofloods are the best, but you said something about 3200k bulbs being ok for interior daylight scenes? Why is that, does it give a cool look or what?
2. What about for interior night scenes? What color temp for the practical bulb is best? 3200 or the blue photofloods?
3. At 4:46 into this documentary on the making of The Shining, you see Kubrick on the floor with a bulb taped to his chest used as diffused fill on Jack's face. What kind of bulb do you think it is? Blue photoflood? Any guess as to the wattage?

Thanks!!
 
It's not Kubrick with the bulb taped to his chest. That's the camera op. There are three guys down there: the cam op with the bulb on his chest, an AC to his right, and Kubrick, to his left. You can see Kubrick's left arm and hand in the frame: the dark blue sleeve of his jacket. Kubrick is using his hand over the bulb, playing his fingers as a moving cucaloris (handalouris). The bulb is most likely a standard tungsten bulb that anyone would buy and put in their table lamp. He was probably using Kodak 5247, a tungsten balanced color negative we used in the 70's and 80's. We are only trying to use daylight practicals these days because the RED likes daylight. Most all practicals one finds in homes now are tungsten bulbs and 4000k or so compact fluorescents (CFLS). I've been using daylight balanced CFLs in my translucent half umbrella China balls since using the RED. Seems to be better than the 3200 or 4000 k CFLs. I say try the CFLs before you go to CTB gels or blue bulbs - B and H has a bunch meant for photography and they might not have a nasty green spike or be poorly balanced.

The handalouris trick works great for imitating firelight as well. Have your gaffer put on leather gloves, and CTB and orange gel up a 1k open face light, and put it on the ground to get the same angle as a fire. Your gaffer can play the light through his fingers on your talent, working with the emotion or dramatic intent of the scene. Or you can do it yourself.
 
You must log in or register to reply here.
Back
Top