I would like to make a ring light( also to be used as a eyelight) around the lens , for an upcoming film shoot, and I was wondering what would be a good working size, design and what kind of bulbs, with what wattage would be suitable for this?, I was also considering including a dimmer. Thank you for your suggestions and advice.
There's a couple of things you could do, I think that chimera may make one, www.chimera.com (no I don't rep. Chimera) or else you could make one out of a piece of aluminum about 1/8" thick plate and cut it to the diameter that you need. Kind of like a speed ring, but it depends on the diameter of the lens barrel verus how big to cut the circle on the aluminum. If that doesn't work, try bastardizing a small household scoop lamp, (am just looking at one in my office right now), make an eye lite rig out of it. As far as the wattage of bulbs you need that depends on what kind of stop your looking for during the shoot. You could try mounting little 20 watt JC type bulbs (12volt) or go to 20 watt, 120volt type. If heat is factor working close to a persons eye, try using a bunch of kino-flo's, "micro-flo's", fixtures, come in 100mm & 150mm in lengths. Or how about pulling out the Christmas lites a little early this year, and string them around the matt box, colour temperature would be very warm somewhere around 2400-2600K. As far as mounting of the ring lite, you may make system where it could slide on the mat box rods, or suspend it off a French flag. Just my thoughts for the day
Milwaukee based Cinematographer
I would use MR16 low voltage lamps. These are available in several focus range from floods to spots, run at 12v and would work well through rosco 216 or the like. You can also buy them in 20w,50w,100w and 150w I think. The number of lamps depends on your application, the closer you move in with the camera to a face, the further your lights will be from your subject. An eye closeup therefore may require a very small rig, where as if you were going for the music video look of the subject lit seperately from the b.g. then you might need a large rig with plently of lamps. I would make several sized rigs with removeable lamps which can be swapped in or outl. A standard household dimmer should suffice.
Director of Photography
I got this tip from a tricks of the trade section in AC's web page archives, in this case by George La Fountaine, ASC: Use a GE (or any other brand I suposse) ten-inch circle shaped fluorescent lamp. It fits perfectly around the lens and has just to be colour corrected.
Sorry, You only have two options in this case. 1) Use a low voltage electronic dimmer 2) Use a Variac set at 12v ac and then dial down from there. Good luck, Dan C.
A fun light that I've use on occasion is Christmas tree clear lights wrapped around the matte box or hung on a C-stand. You can dim them with a Variac or other dimmer. I've also rewired them in series to run on 12v to use inside of cars. It adds a little sparkle to the scene
Director of Photography
Stills That Move, Pasadena, CA
Sorry, you rarely have only two options :
1. You can use MR16's with 110v. filaments (they do exist) 2. You can run bulbs in series to get up to 120v (that would be ten, wouldn't it?) Note: they would all want to be the same wattage) 3. You can get a small step-down transformer to run the ringlite and then plug that into a dimmer. Note: some household dimmers cannot tolerate the inductive load of the transformer and die. You should be able to find household dimmers that are designed to work with Lightolier track- lights which have individual trnsformers on each fixture 4. You can run them all in parallel and feed them with a variac. If you do this, you might want to use two variacs with one set at around 40% or 50% (totally non-critical) This essentially "spreads out the scale" of the second one so that you do not accidentally over volt your ringlight. 5. You can build your ringlight using tracklight fixtures that have their own transformers 6. You can find an electronic power supply an use that (AC or DC) It will have to be bigger than you think once you add up the amperage of all those cute little bulbs.
Two other suggestions: Consider using MR11 globes which are only 1 1/8" in diameter - you can space them closer together
You might want to go shopping for a big bundt cake pan to use as a reflector and cut the center out , since the center "tower" is too small for most lenses.
If you build a reflective trough like this, you might want to go with peanut bulbs (wedge socket bulbes that are about the same size as the old AG1-B flashbulbs) You can get them closer together and /or ditribute them however you want - stick a piece of bailing wire on each socket and you can bend them around to put them where you want.
I don't mean to sound pissy , this is a wonderfully diverse list, and many of the contributers have a great deal of time and experience creating innovative solutions to challenges (or fixing other folk's $#%^-ups.) I myself am but a youngster on this list. Be careful when you state things categorically.
Mark H. Weingartner
Lighting and VFX for Motion Pictures
Hey, Mark is right again...as usual.
And there are many more options as well. One of the first considerations should be what is the purpose and quality of the ring light? Is it an eye light for a sparkle or is it a key light for fashion? Or in between? Hard or soft light? The options on how to proceed from once the preliminary questions are answered are, indeed, endless.
One note on the use of the MR lamps. It has been my experience that the low voltage MR 16 lamps are very sensitive to shock. That is... the filaments don't like being knocked around too much. The 120v MR's are more sturdy in filament design and likely to be more durable.
Hope this helps.
Jim Sofranko NY/DP
Kino displayed a very cool, or I should say warm, ringlight at ShowBiz Expo. It was a kino tube, maybe a 3/8" dia., forming a perfect circle about 8" diameter. Temp was corrected to tungsten, it looked pink to me, and was clearly designed to cast a circle in the eye, not really bright enough to light anything unless it was very ECU.
You can examine strobe ring lights for reflector design. They are made by Pro Foto, Broncolor, and Hensel. They are very close to the bundt pan config.
Normal tungsten kinos always look a little on the magenta side of neutral but they seem to photograph well.
Director of Photography