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practical lighting, How do I get the cone effect from lamps?


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#1 Ray Lavers

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Posted 03 June 2010 - 11:01 PM

I'm shooting some interior night stuff in a living space. Using lamps as practicals is there a particular bulb I should use to get that cone effect to come out, without blowing out the lamp shade? Also when faking the practical light, what gel is best to use to get that nice yellow tinge? I'm using tungsten balanced fresnal source to fake it.

When doing moonlight are there any good gels or gel combinations to use? I'm using an HMI source. I have hear of mixing CTB with green.

I'm pretty stressed any help would be much appreciated.

Ray
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#2 Phil Rhodes

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Posted 04 June 2010 - 01:44 AM

Sorry.... "cone effect"? Are you referring to a visible beam of lighting emanating from a source? If so, that's more to do with having some haze in the air than anything else, although small, point sources of light will produce a better-defined shadow. Can you find some images online that demonstrate what you're after?

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#3 Daniel Smith

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Posted 04 June 2010 - 06:24 AM

For moonlight I'd suggest 117 Steel Blue. It was used on the video I gaffered here:

Bear in mind however this was used on a 3200k tungsten, not a HMI.

As for practical lamps, I'd suggest hiring some dimmers (or building your own) and buying a selection of cheap tungsten bulbs (between 50/150watt). You can warm them up by dimming them and control the luminosity to an exact level. Call me lazy but I love working with dimmers, gels are just a pain.

Edited by Daniel Ashley-Smith, 04 June 2010 - 06:27 AM.

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#4 JD Hartman

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Posted 04 June 2010 - 10:57 AM

If the shades are too "hot", ND the inside of the shade. A pain in the ass really. Easier to swap out the globe for a lower wattage. Just dim your Tungsten lights down to match the practicals.
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#5 Ray Lavers

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Posted 04 June 2010 - 02:07 PM

Hey people,
Thanks a ton for getting back to me so quickly. By cone I didn't explain properly I made that term up myself haha. I mean when a practical makes a nice line up the wall. It happends naturally however I feel like their must be a way of exaggerating the effect. This is a photo from Gregory Crewdson (not a painting). Maybe if i ND the lamp shade with a stronger bulb perhaps I I could achieve a similar effect. I was just curios if there were any specific method that works best. I was thinking of trying some straw maybe to get a good yellowish backlight.

As for moon light, the steel blue isn't bad. I want to stay away from CTB because, it just looks like a ctb gel.


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#6 Daniel Smith

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Posted 04 June 2010 - 03:10 PM

I think some light ND on inside of the shade would work well. Run some tests with a stills camera.
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#7 Mathew Rudenberg

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Posted 05 June 2010 - 02:32 AM

Hey people,
Thanks a ton for getting back to me so quickly. By cone I didn't explain properly I made that term up myself haha. I mean when a practical makes a nice line up the wall. It happends naturally however I feel like their must be a way of exaggerating the effect. This is a photo from Gregory Crewdson (not a painting). Maybe if i ND the lamp shade with a stronger bulb perhaps I I could achieve a similar effect. I was just curios if there were any specific method that works best. I was thinking of trying some straw maybe to get a good yellowish backlight.

As for moon light, the steel blue isn't bad. I want to stay away from CTB because, it just looks like a ctb gel.


Ray


The cone effect you speak of will naturally happen when a bright globe is in a practical with a similar lampshade to the one in you picture. Preventing the lampshade itself from blowing out can be done using ND, or by simply using a thicker lampshade that absorbs more of the light that hits it directly.

If you're using an HMI for moonlight, remember that it is a naturally blue light source already. How blue it is depends on the color balance of your film or that your digital camera is set at. It also depends on the camera you're using and the level of saturation you're finishing at.

I find a 56k 'moonlight' at a 32K setting to be too blue for some digital cameras (like the venerable old F900) but just right with less color sensitive cameras like the red. I don't think I would add blue to a HMI if shooting at 32k unless I wanted a really particular effect.

Green is quite commonly added to moonlight for a more stylized effect. Remember that moonlight is merely sunlight reflected off the moon's surface, so realistically speaking it should be the same color as sunlight, maybe slightly modified by the color of the moon's surface that it is bouncing off of.

That being said, decades of movie goers have been acclimatized to the visual cue that blue light = nightime.
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#8 Gustavo Brum

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Posted 08 June 2010 - 02:41 AM

First, remember to use "clear" globes or transparent globes because they will give a better shape and darker shadows. It will look more dramatic. If you want less dramatic, use the opaque globes.

Second, have some "Streaks n' tips" spray which is basically spray paint used in human hair.

Make sure the globe is off and COOL to the touch!!! This is very important, because if the globe is hot it will explode on your face.

Use the Streaks n'tips in the center of the globe, the side facing the camera, because if you dont do that you will have a very menacing hot spot. The Streaks n'tips will "slow down" the hot spot.

Dimmers are good, but on household globes they will make the globe change its color temperature enormously.
The lower the intensity, the more red the light coming from the globes. So it has a price.

Also you can use ND gels underneath the lamp, so you have one intensity on the top of the light and another on the bottom, this is an option in case your subjects are sitting close to the lamp, or you have some piece of furniture or props that are white (or lighter color) and and will expose too bright.

Edited by Gustavo Brum, 08 June 2010 - 02:42 AM.

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Visual Products

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Media Blackout - Custom Cables and AKS

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Metropolis Post