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Flaring From Overhead Fluorescents


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#1 Bryce Fortner

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Posted 21 September 2006 - 02:11 PM

Hello,

I'm shooting in a hospital location this weekend and we have some tracking shots looking straight up into the ceiling; acting as a stretcher 'POV'. I've had bad experiences in the past with getting flares from existing fluorescents... which can be pretty ugly! Outside of shooting with an eyebrow and hard matte, does anybody have any ideas/tips on how to avoid getting these flares? I'm shooting with an S16 SRII and Zeiss super speeds.

Thank you!
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#2 Michael Collier

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Posted 21 September 2006 - 04:28 PM

If possible, you can try and lower the relative intensity of the unit. Flaring will occur as it would normally, but like all things light, if its not as bright, the flare will be less noticable (to the point where it may be invisible) You can throw Neg green on all lights (as apposed to filtering the camera or replacing with kino tubes.) this will reduce the actual light output of the units. Then boost the level of light inside much higher so you stop to well over what you would if you did not have additional lighting. That will make the flare (which is just a picture taken of the reflection through the glass) less intesnse, and if you get it right, it would be barley noticable, or even invisible. The problem you will run into is eventually you will reach a point where the floros are no longer convincingly bright. if you can get right on the edge of that though, there should not be enough relative light to flare the lens.

Also what type of floros are these? Do they have the plastic diffuser in front, or just the egg crate in front? A diffuser will spread light output over a larger region, bare bulbs will have more light concentration on the tube, making flaring more likley and visible.
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#3 Dan Goulder

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Posted 21 September 2006 - 05:38 PM

I've had bad experiences in the past with getting flares from existing fluorescents... which can be pretty ugly! Outside of shooting with an eyebrow and hard matte, does anybody have any ideas/tips on how to avoid getting these flares? I'm shooting with an S16 SRII and Zeiss super speeds.

Unless you really need the extra stop, you'll get less flare from using standard speed primes. Short of relamping the shooting location, you should get decent results from filtration, using an FLB for tungsten stock, or an FLD with daylight stock.
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#4 timHealy

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Posted 21 September 2006 - 07:00 PM

generally speaking, I have always thought one needed a strong specular light to get a flare. I didn't really thinka soft light of any type would flare. BUT boy was I wrong! A fluorescent can flare a lens!.

I think you have several ways to solve the problem. One (which you are already are doing) is to use flags and matteboxes to cut out any lights out of the lens. You can use the lens like a mirror by looking right into it and trying to see if you have any reflections of any light s and get rid of it. If a light is in the shot, there is not much you can do about it.

As someone mentioned, you can use gels, but as you question did not include anything about color correction, I would use ND rolled onto the bulb itself putting the seam behind the bulb. I assume these bulbs are not your only lighting source. If they are your only lighting source this would change your exposure and may not be a solution.

But also I would use newer lenses with newer anti halation coatings. If you are using an older Zeiss or Angenieux lens with older anti halation coatings or no coatings at all, nothing may help if the light is in the shot. Any idea how old your lenses are?

Best

Tim
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#5 Bryce Fortner

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Posted 22 September 2006 - 11:11 AM

Thank you all for the advice. Unfortunately this will be a total run and gun affair. We only have the location for a few hours (at night) and I won't really have the time to re-lamp or gel the units... Though, as this will finish digitally I'm not too phased about color temp. The camera package is being donated to us, so I'm afraid that super speeds are my only option (though I wasn't aware that standard speeds would flare less... do they just have better coating on them?). I think I'll try to light the talent with a seperate source and bring them up to a stop where I shouldn't have to worry about the intensity of the flaring... and from there just cross my fingers.

Tim, I remember I had the same thought you did about a soft source not flaring a lens... imagine my surprise in the telecine suite when the actor's face was masked by this huge flare (and there was no discernable flaring in the eyepiece)! Fortunately, because it was a sci-fi flick, people seemed to buy it and though it was intentional... I cringe every time I see it.

Anyhow, thanks again guys!
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#6 timHealy

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Posted 23 September 2006 - 10:49 PM

Tim, I remember I had the same thought you did about a soft source not flaring a lens... imagine my surprise in the telecine suite when the actor's face was masked by this huge flare (and there was no discernable flaring in the eyepiece)! Fortunately, because it was a sci-fi flick, people seemed to buy it and though it was intentional... I cringe every time I see it.

Anyhow, thanks again guys!


I basically had the same experience. I was shooting a student film and the crew size was undermanned. I had not seen a discernable flare in three shots where I used a single tube Kino as a backlight and with the rush rush rush did not set a flag to cut the light out of the lens. We were also shooting in a place where the ceilings were low and the Kino backlight was out of frame. Sometimes I used a french flag just above the frame but for some reason the AC kept lifting it up when I left the camera to adjust lighting, but not seeing anything discernable, I let it go. Boy was I surprised at what kind of soft flare I got that kinda looked like a light leak

I learned an invaluable lesson on that one. Be safe and cut all light out of the lens.

best

Tim
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