Cinematography Mailing List - CML

Fluorescents & Daylight


I'm shooting in a hospital with very little control on the hospital fluorescents and windows. Not sure where to go with lens filtration. I'm shooting 5279. My problem is do I filter for the flos with an FLB, what happens to the daylight? Also tungsten? or do I stick on an 85 and let the flos go and clean up in post. If the opp arises I'll gel the windows or flos and feel a bit more in control. Sorry if this message doesn't quite make sense getting abit fraught. Would rather be thinking about the visuals than the technicals. Den(wish I had more experience)Pollitt

Filtering the camera lens isn't going to change the color difference between mixed light sources. It all sort of depends on how dominant one source is over another, but in general you should start either with trying to match your sources (swapping bulbs, gelling windows, etc.) and THEN think about filtration. Or learn to love a mixed color temperature look!

Since you are shooting in 35mm, I would recommend the new Fuji F-500D "Reala" stock, which uses a fourth color layer to inhibit some of the green spike effect when shooting under fluorescents. Won't correct it completely, but it will get you closer by losing some of the greenishness in the fluorescents. If the bulk of your lighting though is tungsten mixed with Warm White fluorescents, you'd probably be better off with a tungsten-balanced stock. But if you're talking about Cool Whites mixed with daylight mostly, I'd look into using this new stock. (I'm less enthusiastic about any of the Fuji & Kodak 500 ASA stocks in 16mm, but can recommend F-500D without reservations in 35mm.) It's slightly more pastel and has a little more shadow detail than its tungsten version.

There's still no substitute for correcting the lights to match -- it gives you more options. I haven't used the FLB or FLD filters, for fear of losing too much light, but I have used milder correction from the LLD or an 812 filter, just to knock back some of the blueness of Cool Whites on tungsten-balanced stock, doing the bulk of the correction in post.

David Mullen
Cinematographer / L.A.

I'd buy a roll of Minus Green and lay it under the flos on top of the plastic covering the fixture. Cheaper and faster than tube or gelling the windows. Get a color temperature meter and a swatch book and meter the flos. Hopefully the individual tubes will all match and you will only have to buy the minus green that kills the green spike. Then pick what you want to appear neutral -- windows or flos -- and balance the color temperature to the film for that source. It's not that technical.

Mark Woods, Director of Photography

>I'm shooting in a hospital with very little control on the hospital fluorescents and >windows. Not sure where to go with lens filtration. I'm shooting 5279.

I am going to assume that you are shooting in a documentary style, and will not be able to add any of your own supplemental lighting.

I once spent two weeks in a hospital, shooting a verite' documentary at The Children's Hospital of Pittsburgh. (When I say two weeks in the hospital, I really mean it!... we did not leave the building for a fortnight... I slept in the inflammatory bowel disease clinic!)

Here is how I tackled the lighting challenges :

During daylight hours, I capitalized on the window light, using an 85 filter on the lens for color correction. For the most part, I left the fluorescents off (the room I was in had a southern exposure). I was lucky in that the room had some sheer curtains on the windows, so I was able to diffuse direct afternoon sun with ease. The piece I was shooting was quite serious in nature, so the high contrast ratio played to strength. However, I was careful to expose for shadow detail, letting highlights lean toward overexposure, since negative film has a great ability to handle highlight overexposure. I also avoided shooting directly toward the window, which would have "blown out" terribly.

When evening rolled around, I would turn on the fluorescent lights (after checking the lamp type, which, in my case, was cool white... you might be luckier. a lot of hospitals are using high output, full spectrum tubes these days) I'd then pull the 85 filter and shoot with a clean lens.

However, I did not simply whack on the overheads. I took care to "shape the light" in order to keep the moody atmosphere of the room. (tense and serious doings in front of the lens, remember?) . In order to accomplish this without using any tungsten lighting, I removed the lamps from the ceiling fixture directly above the bed (having gotten permission from the hospital staff of course). In almost all hospital rooms, there is a "wall fixture" over the headboard of the bed. Usually a fluorescent fixture with a two level switch. I made sure this unit was on (at the high setting) whenever I was shooting.

This arrangement put a nice, high contrast "side light" on the hospital staff and visitors, while lighting the patient with a full facial light. The overhead fixture in the background did a great job of lighting the walls, but If I had left the foreground overhead unit lighted, The whole scene would have taken on a "flat" contrast, and would not have helped conjure the mood the scene demanded.

Again, I exposed for shadow details, letting the highlight overexpose about a stop or so, having exposed a gray chart in the "Low light" side of the room. The timer was able to add magenta to the scene to counteract the green cast from the fluorescents with little difficulty. I chose not to employ any magenta color correction on the lens, since I did not want to be "robbed" of a stop while shooting.

5279 has a great color latitude. You will be pleasantly surprised by it's ability to handle the florescent environment, IF you let the lab timer (or telecine colorist) know to make the correction! (remember communication is KEY!)

Joe Di Gennaro, soc
Director of Photography

Adding to Joe DiGennaro's observations :

Having lit a lot of doc and medical stuff in hospitals in situations where we had very little control over ambient light and very little opportunity to add much in the way of light (in OR's and ICU's they get VERY touchy about anyone plugging in ANYTHING) I found that one cheap trick that one can employ to shape the fluorescents sometimes is to hang newspaper as teasers - it seems to scare people less than blackwrap - it doesn't weigh much, and you can read it while waiting for your doctor to come back.

Also, beware opening up fluorescent fixtures in "clean" areas.

The crap that collects above the diffusers falls down and freaks the staff out. Mind you, if you go into the typical OR trauma area and stand on things to set lights, you will find that there is often a big layer of dust on the top surfaces of cabinets and stuff - so much for sterility.

If you are augmenting the lighting, be sure to get in contact with the building electrician who will know where the breaker panels are and which outlets you should and shouldn't use. An innocent mistake on your part could shut down equipment vital to someone's care and will certainly ruffle the feathers of the hospital staff.

Mark H. Weingartner
VFX, Photography & Lighting for Motion Pictures & Television

Everything mentioned here in response is good and has merits, but since this all seems somewhat new to the original poster let me toss out one variable, which we've all encounter before when using ceiling practicals :

Many times the fluorescents won't match on a tube-to-tube basis. Pretty uncommon for all the fixtures to have all the very same model "tubes" of approximately the same burn time. What we usually find are Cool Whites and Warm Whites in the same ceiling, or worse yet some really ancient green-makers out in the hallway and something entirely different on the other side of the hallway window in the office or room where we're shooting principals. And yes, it always looks worse in the transfer, you really must stop, look, and think about it while standing there on location. So in the end it does again come down to experience and judgment by eye.

Preplanning may be 90 percent of production, but 90 percent of that preplanning is compromise, change, and adaptation.

Jim Furrer, Director of Photography
Dark Street Films / VGG Systems, Inc.

And yes, it always looks worse in the transfer, you really must stop, look, and think about it while standing there on location.

A little trick that my D.P. showed me: he got an old 4" x 4" colour enhancer camera filter and cut in half, one for each of us. This filter amplifies the colour in floris and even HMI's. It works so well; it amplifies the greens or magentas so you really can judge colour by eye.

Working hospitals are notoriously not friendly to film production. Depending on the location, it might be faster, easier, and politically better for hospital relations, to gel a few windows with plus green instead of gelling 20 or more fluorescent fixtures to match the daylight. Then in the transfer, just correct the light to white. It might also help you by bringing down the exposure through the windows a little bit if you really have that little control and are not lighting through them.

If you shoot using uncorrected fluorescents, intending to correct in post, you may want to consider using some of the hospitals actual fluorescent tubes in Kino fixtures so you can have some lights of your own that match the color, and will give you more control.

If you get a chance to scout, bring a color meter and a swatchbook so you can find out exactly what kind of gel you need to do the job. And don't just trust the Mired correction on the gel's specs. I've found it's much more accurate to hold gel combinations over the meter's sensor. Then just find the right combination of gel to get the readings that you want, and that's exactly what you need. I always carry a Lee Cinematographers Edition swatch book with my color fits quite nicely over the whole sensor.

Craig Kief
Gaffer, LA

If there are a lot of windows, I personally would go with correcting to daylight, lighting your action/actors with HMI's. Just because magenta windows and spill seem weird to my eye. On top of that green (which you will get from your fluorescents) feels somewhat natural in a hospital environment. Depending on your bulbs in the hospital you might consider warming up your HMI's accordingly and letting daylight streaming through windows go a little bit cool. Otherwise your fluorescents might tend to go towards yeelow-greenish, which I personally find unpleasant.

Florian Stadler
Cinematographer, L.A.

Look into Fuji's new 500 Daylight's made with a fourth color layer to help eliminate that green spike from your flouro's. I saw a demo of it last Saturday and it certainly does what it claims. Maybe you can get a test roll from Fuji and run up to the hospital before the shoot for some tests, or check out RGB in Hollywood to see if they might have this stock on 35mm still rolls and shoot some shots with your standard 35mm stills camera.

Ken Glassing
Operator/ Dp
Los Angeles

If you have the opportunity to try our new Fuji Reala 500D, I think you will find that your situation is precisely what this new stock is designed for : "The Reala 500D is an ultra-high speed, daylight-balanced, color negative film stock utilizing Fuji's proprietary "4th layer" technology.

The 4th layer is designed to help more realistically reproduce color as well as to minimize the "green spike" resulting from shooting under fluorescent lights and other artificial lighting sources. This 4th layer technology is particularly helpful when shooting in daylight mixed-light situations."

I'd be happy to get some to you to test if you wish.

Andy Coradeschi

If you can retube the fittings & your production can afford it this would be the way to go. Using cool white tubes would give you a colour temp around 4700'k so it's in between your daylight 5600'k & your tungsten practicals approx. 2800'k.

If your production can't afford the full cost of retubing, try talking to the hospital maintenance dept. in the hospital about splitting the cost. They normally try to tube these fittings with some sort of daylight balanced fitting.

From a cost point of view depending on the number of windows & size of each, it will probably be cheaper to correct the fluoro's both from a labour point of view & materials (gel etc.)

Also if you gel the windows with standard gel you are getting into a possible reflection nightmare as well as getting the gel smooth enough that you don't see ripples or kicks in the gel itself. If the gel remains in place for any period of time & you have any temperature changes you get condensation on the gel. Acrylic gel (costly) can cut down the reflection problem, not necessarily the condensation problem.

With regard colour temperature meters, personally I feel they are a must. Having gelled various coloured tubes for both green & colour correction on many locations,& cringed when looking at the shot by eye, later seeing the dailies looking great, I would swear by a good calibrated colour temp meter & lee swatch to decide what correction to use. Almost every fluorescent tube has a different green spike(depending also on age) & a lot of these spikes don't read to the eye (even though the human eye see's best in the green spectrum).

And if you have to shoot night interior in this location & you are worried about the fluoro’s looking blue you can use HMI's or correct your tungsten lamps to match.

James Mc Guire
Gaffer, Dublin

You also might try Kodak's 250 Daylight film. It has always handled mixed sources (tungsten, daylight, florescent) very well. even Mixed sources in the same frame.

Steven Gladstone
Cinematography Mailing List - East Coast List Administrator

I had a shot for one sequence in an OR and it was a live birth. I had a duffel bag with the camera and a couple of tungsten 1k lights. I was on call during the due date and when it happened I made my way into the hospital with the duffel bag and into the room. The doctor and birth had pre-approved everything but the hospital didn't know. I set up two 1k tungsten lights so they would bounce off the ceiling-this overpowered the tint coming from the hospital lights-it was an insert shot for a feature film. I stood next to the doctor for about 12hours with camera in hand. The producer was at the door while the director was in a corner of the room just waiting. I saw much more than I expected but for this shot this lighting technique was best. I know it would produce an even flood like feel but it was just an insert shot that would fit in with the fake birth sequences shot elsewhere. This might not help for long term shooting in an OR and color temperature problems but it might give some people ideas to over come hospital light by overpowering the existing light to create the same hospital feel if that is your intention.

Brian Fass
New York, NY

I have done a lot of Hospital spots in the past few years. I agree that some of them are not always excited to have us there. You have to feel that out first thing in the morning because that does unfortunately make a difference in your lighting approach. When the job is said and done you want your client to be invited back so you in turn will be invited back.

The first thing I do is order Kino Flos, lots of them. Mostly 4 footers. Then when we get to the hospital I get in touch with the maintenance person and make friends. I then ask if we can borrow a case of spare flo lamps and use them in our Kino fixtures. Now the green is the same and can be dialled out later. If we need bigger guns we usually have good luck with making gel packs for HMIs. 3/4 or 1/2 plus green usually and maybe a little 1/4 or 1/8 CTO depending on the house flos. The only real challenge is getting the correct house flos for the Kinos. Sometimes the house lamps are different in different departments or worse yet, they ordered a different lamp this month and half the hospital is one type and half another.

Mike Gillis
Milwaukee Gaffer

>I then ask if we can borrow a case of spare flo lamps and use them in our Kino >fixtures

It's a whole lot easier for everybody if you just order a bunch of Kino tubes of your favourite flavour and stick them in the ceiling fixtures. It works great. Then have a few floating around on C-stands to use where you want to augment, and you're all set.

Phil Badger, gaffer, LA

I've got a slightly different approach for the mixed-source hospital environment. First off, you're best choice is re-lamp everything and stay within a "daylight" color temperature. If your world (and budget) can't oblige the best solution there are always options. You've got some daylight through the windows and PROBABLY cool white fluorescent tubes in the ceiling. Let's assume that your dominant light source is the fluorescent and these are cool white (but check the info on their tubes and get a spec sheet to make sure). No doubt there are hundreds of tubes, and you can't possibly re-tube on your budget. Don't fight it...go with the flo (sorry, couldn't resist).

My favourite for a quick and cheap solution is to 50/50 mix daylight tubes and tungsten tubes with 1/8 or 1/4 Plusgreen gel over these fixtures. This combination yields a source approximating the 4200K color temperature of the existing fluorescent sources and adds that touch of green (to better match the fluorescents) that you can pull out in your transfer (or with your white-balance button on a video shoot). The spectral distribution of color is quite good for the faces in your foreground, and the background should hold nicely since the nominal color temperature is matched. The windows will tend a bit blue, but that's a reasonably well-accepted convention. If daylight is a big player with many windows, then go with that source and change all the ceiling fixture tubes and play with your added sources to match. But if you're running and gunning around a hospital with cool-white fluorescents, it's tough to beat the mixed tube set-up with a touch of green.

Bruce Aleksander
Lighting Designer +

Got a mixed lighting situation where I have to do some major color correction. Location is large office with fluoro's, plenty of windows and these pesky tiny halogen lights. Everything will be in shot due to long steadicam shots and super wide establish shots. Colour temp of fluoro’s came out to 4000K (with a green spike), halogens were approx 2900K. Assuming fluoro’s were Cool Whites. I want to use the floors because there a great looking designer light fixture (and there's about 50 of 'em).

Shooting 7279, no 85, and planning to 85 windows (ones directly in shot anyway)and use all tungsten lighting. Still debating if I should go with Fluoro filter gels on the fluoro's or 1/2 or full minus green because the script calls for a "cold" look anyway. If Fluoro filter gel isn't readily available, what's the alternative? (not feasible to replace bulbs)

Dave Luxton
cinematographer - filmmaker
Edmonton, Alberta, Canada

Subject : Mixed lighting

>If Fluorofilter gel isn't readily available, what's the alternative? (not feasible to >replace bulbs)

Look into Fuji's new 500D stock. It has a fourth layer technology that knocks out the green spike in Flouro’s. I've seen the demo here in LA and it works like a charm. 500 daylight balanced stock, shoot with daylight kinos and small 1200 HMIs and you won't have to gel a thing!

Ken Glassing
Los Angeles

If you can't get fluoro filters there are several alternatives. But you still have to contend with the same two basic issues: 1) you have a green spike coming from the existing fluorescents; and 2) you have light sources with disparate color temperatures. The best solution is to replace the existing fluorescents with color corrected tubes, but according to your posting, that is not feasible.

Ken Glassing's suggestion to augment with HMI's and daylight Kino's, then shoot Fuji REALA 500D would deal with the green spike, but it wouldn't change the fact the existing fluorescents are outputting 4000K, while the daylight sources are at 5500K, and the halogen practicals are at 2900K. REALA also wouldn't help you achieve the "cold" look you're after because you'd be using daylight film, a few properly balanced daylight sources, and several comparatively warm sources.

To solve this you could gel the halogens and existing fluorescents to 5500K. Then all of your sources would match and you could add an 82 filterÑor something from that family--to the camera to cool off the image.

One big problem I see, though, is that there are fifty fluorescent fixtures at the location. I don't know how big your crew is, but that's a lot of gelling, especially if you plan to do it tube by tube.

If I were in this situation I would forget about gelling the fluorescents altogether and gel the other sources instead. If you want to try the REALA 500D, then warm the HMI's (assuming you can afford them) to 4000K with 3/8 CTO (or thereabouts). Use the same gels on the windows. Then cool the halogens from 2900K to 4000K using 5/8 CTB. At that point all sources will be at 4000K and you can filter the camera back to 5500K with a combination of an 82C and an 82A filter. Of course you'll have to compensate by opening up one stop. If you want a colder image, add more blue filtration to the lens rather than the lights.

I wouldn't bother renting Kino Flo fixtures for any reason on a shoot like this. I'd just go to Home Depot, buy some $7.00 shop lights, load them with the same tubes that are in use at your shoot location, attach them to C-stands with Mafer clamps, and use those as your floor lights. Flicker is not issue in this instance because the existing fixtures confine you to using HMI-safe camera speeds. The Home Depot units will definitely flicker, but at the same rate as the practicals.

The same theory applies if you want to shoot 7279 500T. If you don't want to gel the fifty existing fixtures, gel the other sources instead. If you're augmenting with tungsten, cool those lights from 3200K to 4000K, cool the halogen practicals from 2900K to 4000K, and warm the windows from 5500K to 4000K.

Of course if you're using any film stock other than the Fuji REALA, you'll have to contend with the green spike, too. The best way to do this is to add Plusgreen to all of the additional sources; e.g., the tungsten will have 1/2 Blue and Plusgreen, the halogens will have 3/8 CTB and Plusgreen, and the windows will have 3/8 CTO and Plusgreen. This will put all of the light sources at 4000K with a green spike.

Then put an FLB on the camera to rebalance to 3200K and remove the overall green cast. To achieve a colder look, you can use the aforementioned 82 filter. Or you can use a CCM filter on the camera to eliminate the spike--in lieu of the FLB--then add a light amber filter--like an 81A or something from the 81 family--to partially correct from 4000K toward 3200K.

If I'm wrong about the fifty fluorescent fixtures and you do indeed have the time and manpower to gel them all, I would cover each of them with Minusgreen to eliminate the spike and add Lee 1/4 CTO to warm them from 4000K to 3200K. Then gel the windows with Full CTO, gel the halogens with 1/4 CTB to get from 2900K to 3200K, and you're ready to shoot tungsten film with no filters on the camera. Once again, to achieve the "cold" look, add an 82 filter to the camera. For more blue use one of the higher density filters from the 82 family.

Regardless of which approach you take, I'd use my color temperature meter to determine exactly how much Minusgreen or Plusgreen is needed to neutralize or match the spike and use that amount. Using a 1/2 Minusgreen on fluorescents when your meter indicates you need more is going to give you a green cast rather than a cold look. And if you try to time out the extra green in telecine or printing, your other sources will take on too much magenta.

So, the common thread in all of the approaches is to make your light sources match in terms of color temperature and green spike characteristics. If they do, you can easily tweak the overall look with various camera filters or at the telecine and printing stage.

D.A. Oldis
Winston-Salem, NC

How about renting a bunch of kino bulbs and using them in the ceiling ; match either to daylight or tungsten? At that point you can decide to have a daylight and tungsten light mix; or look into putting a little piece of heatsheild and CTB to correct the little track lights. I don't think anyone would see/notice the gel if it is cut correctly. (seems that there are places in LA where you could get a good deal on a couple armloads of kino bulbs)

I suggest no matter what keeping it simple. I think if you eliminate the green spike, you could choose to make either day or tungsten be white, and use the remaining blue or yellow light to highlight.

Matthew Alcorn
Los Angeles

P.S. Seems like in order to expose the outside correctly you might have to gel the window (ND at least); in which case you could gel with CTO, and then use tungsten balanced Kino's; then you're matched.

I just spoke to someone at Philips (UK) who gave me the spec on some of their daylight fluorescents: they have '965 tubes' which are 6500 Kelvin and '950 tubes' which are 5300 Kelvin... if you were to run these in their high-frequency luminaries (around £40 for the 2 bank, 5ft version) I imagine you could shoot with most speed/shutter combinations? (their HF ballast gives you 42-48kHz)

Brendan McGinty
DOP London

Copyright © CML. All rights reserved.