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Construction Lighting Equipment for Night Scenes?


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Hi,

 

I will be shooting a very low budget horror film that calls for half of the scenes to be shot at night.

 

Ideally I want to use one large light source to back light the locations that I will be filming. Also it would be great to use the same light to shoot through windows at night as the main light source for a room.

 

I realize that most films use huge 12-24k HMI lights on cranes to get that effect.

 

The problem is I can't afford to rent that equipment.

 

So ... I was wondering if anyone has tried to use alternative equipment like the sort of lights used when doing street repair and construction work?

 

Driving past the average construction site I am always amazed at how much light they are pumping out onto those locations. The lights seem to be a least be 10K and attached to a pole that can be raised about 20ft with its own genny at the base. Sound familiar?

 

My thought was getting a hold of one of those and attach it to the back of a car or truck and drag it around to the different locations. Add a bunch of CTB to the light and fire it from 20ft up so the light falls on the location behind the actors.

 

Since I will be shooting in a small town and have "friends who have friends" maybe I could get a hold of that kind of equipment cheaply or even for free??

 

I am trying to stay positive, but maybe I am just dreaming?

 

Any insight into whether this would work or not would be great.

Also if you have any other ideas for alternative large light sources, fire away..

 

..Thanks

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Add a bunch of CTB to the light and fire it from 20ft up so the light falls on the location behind the actors.

I'm unfamiliar with the use of either light you've mentioned, but for the construction light you may want to skip the CTB and time it blue in post so you don't lose the stop (maybe by shooting a greyscale through a full CTO)...it's something you've got to test. Of course then you'd have to gell all the other lights full CTO to get them to appear white, so it may be counter-productive, unless you can't find a powerful enough "moon" to get yourself even wide-open.

 

If all else fails, you can always try to swing it with a handful of 2k's and 1k's.

 

maybe not very helpful, but that's my 2c...

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So ... I was wondering if anyone has tried to use alternative equipment like the sort of lights used when doing street repair and construction work?

 

I really don't know about those. You might wanna go visit one of these road repair sights and just film it to see if there's any flicker. Also, I've noticed on occasion that those lights can be pretty close to being daylight balanced.

 

I'm interested in the lights properties, let me know what you find out. I know some people in construction, I could find out what they're all about as well. :)

Edited by Jonathan Bowerbank
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Hi,

 

I've seen the things you're talking about. This is wild speculation, but from the colour (which isn't super-cold as it would be if it were mercury vapour) I suspect some of them might be MSR lamps. If I'm right, this is good news, because MSR has a pretty good CRI and emits at about 4000K, making it correctable to either daylight or tungstent with minimal loss. You'll have to ask someone with a reasonably deep technical knowledge of them exactly what they are, or you could just shoot a test, even with a stills camera if you're shooting film, or with your real camera if it's video. If it's video, I suspect you'll be absolutely fine with them, although I very much doubt they'll be flicker free.

 

Phil

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So ... I was wondering if anyone has tried to use alternative equipment like the sort of lights used when doing street repair and construction work?

There's no reason for the generators that run those lights to be frequency controlled. As a result you might run into unsolvable flicker problems since the light's "flash" rate could be anything.

 

If you could find a construction light that was designed to run off its generator or commercial power you could probably rent a proper frequency controlled location generator and plug the construction lights up to it. You'd have the expense of a proper generator rental but still save money on the the light rental end of the equation.

 

I agree with Phil about CRI, I've seen enough of those lights on road construction sites, etc. to believe they probably do have pretty decent color rendition.

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Well its good to hear that it might be a viable option. :)

 

I didn't even think about the flicker issue.. but then again thats why I posted.

 

BTW the film will be shot on HD with the Panasonic HVX200 so I should be able to color balance to moonlight or daylight.

 

If I was to go the 1 or 2k way how many would I need to create a decent moonlight look?

 

Is it best to just go for mostly backlighting at night with both subjects and background elements?

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i am not sue what they call them in the construction business, but many in film call them construction light towers. They get used alot for lighting large areas where there is no street lights, like when shooting in the woods (when the film lights go out it gets really dark!) or lighting your trucking areas when they are parked at a farm or someplace remote. They can be widely green or magenta, but if it is far enough away the colors will mix and may balance out a bit. Hal has a worthwhile point that they are construction generators and have no need to be crystal. depending on the type you get, it may be easy or difficult to rewire and plug into a film generator. The other good reason to follow that advice is that they are loud. So if you're shooting sound .... enough said. There is no reason for them to be blimped on a construction site.

 

Physically some are more balanced than others. The less balanced they are the harder it is for people to move when one has to make slight adjustments. The towers can usually rotate and since they are not film lights, one usually needs a wrench or two to pan or tilt the heads.

 

Best

 

Tim

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BTW the film will be shot on HD with the Panasonic HVX200 so I should be able to color balance to moonlight or daylight.

 

I think it's common in this forum to assume that everyone is shooting actual film, unless otherwise stated.

 

Since you're shooting video, even at 24p, you should be fine and there shouldn't be any flicker. But this just makes it even easier for you to test it out.

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Hi,

 

> Since you're shooting video, even at 24p, you should be fine

 

Woah, hang on a minute - why is this the case? Unless you're in an automatic synchro-scan mode, which can have other undesirable effects, it's just as possible to get flicker problems on video as film. I've seen 24p video flicker under 50Hz fluorescents, and I've seen 50i video flicker under 60Hz fluorescents.

 

Phil

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To my eyes those usually look like they have a pretty decent green spike in them. Not really a problem with video, unless there should be another light in picture that does not have the same green spike (such as a 1K key light, using the towers as back-light). You said you wanted it blue, then you should probably set your camera on a tungsten setting, see just how blue it is and decide from there. you can either gel or whiteballance on a warm card. Time and resources permiting I always like to gel rather than whiteballance, but gels might cost 20 bucks and 15 minutes rigging all the lights, compared to the 4 second whiteballance procedure...something to think about.

 

Flicker could be hit or miss as was mentioned. Someone said it won't be a problem with 24p video, but I am not so sure. Commonly the HVX's cine-like settings not only put the camera in 24p mode, but also a 1/48sec shutter (180 equiv) so in theory under those conditions, there should be no difference in the capture between the HVX and film. Even if flicker isn't a problem, phase shifting can be. Phase shifting happens in floros and other devices whos color spectrum output is dependent on the phase of the cycle its in. With floros the result is a slow drift from an almost brown color to a green/blue tint and back again. I have seen the whole cycle take upwards of 10 seconds, so when you test pay close attention to that. I have also seen that problem in mercury vapor type lights as well, a likely type of light used in some of those towers.

 

But hey, its video. test it out on the rental shops floor. Go through any shutters you might use (though you might be restricted past 1/48th, heck you may find to eliminate flicker without spending more money on a cine-generator you may have to turn the shutter off (360 shutter) at least you'd gain a stop and need less light and see more into the shadowy unlit portions of frame.)

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Hi,

I used construction lights to light big, big exteriors and at first i was concerned with output and color rendition...and we rented one unit (were shooting on HD F900)...the unit had 4 heads and yo had a lot of control...

The one I used had a built in generator and the arm could go pretty high 15 feet or more...was high enough for me...and the weird thing is that I tested it the night before shooting and the one I got was pretty close to 3200k and the output was huge I gad to stop down....

It worked great and ws really cheap to rent...the big BIG problem is that this type of units bring this hipper loud generators..in my case wasnt a problem the scenes were mos anyway but still...

 

Look at the Inside Man..they used similar units but replaced the heads with Arri X lights I think...

 

well and for getting a hold of this lights see any construction and ask where to rent them or just go online and look for construction lights..I rented this one in Arizona...

 

best

Miguel

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To my eyes those usually look like they have a pretty decent green spike in them. Not really a problem with video, unless there should be another light in picture that does not have the same green spike (such as a 1K key light, using the towers as back-light). You said you wanted it blue, then you should probably set your camera on a tungsten setting, see just how blue it is and decide from there. you can either gel or whiteballance on a warm card. Time and resources permiting I always like to gel rather than whiteballance, but gels might cost 20 bucks and 15 minutes rigging all the lights, compared to the 4 second whiteballance procedure...something to think about.

 

Flicker could be hit or miss as was mentioned. Someone said it won't be a problem with 24p video, but I am not so sure. Commonly the HVX's cine-like settings not only put the camera in 24p mode, but also a 1/48sec shutter (180 equiv) so in theory under those conditions, there should be no difference in the capture between the HVX and film. Even if flicker isn't a problem, phase shifting can be. Phase shifting happens in floros and other devices whos color spectrum output is dependent on the phase of the cycle its in. With floros the result is a slow drift from an almost brown color to a green/blue tint and back again. I have seen the whole cycle take upwards of 10 seconds, so when you test pay close attention to that. I have also seen that problem in mercury vapor type lights as well, a likely type of light used in some of those towers.

 

But hey, its video. test it out on the rental shops floor. Go through any shutters you might use (though you might be restricted past 1/48th, heck you may find to eliminate flicker without spending more money on a cine-generator you may have to turn the shutter off (360 shutter) at least you'd gain a stop and need less light and see more into the shadowy unlit portions of frame.)

 

I've shot some 24P but not much and got the impression that it has to be at 1/48th sec. shutter

speed. Is that incorrect? I'm a little confused because I believe that in a film camera the shutter

is actually a material object spinning at a certain rate that is measured in both degrees and

exposure time (yes/no?) whereas the "shutter" in a video camera is a term for something

happening electronically involving exposure time but the "angle" option isn't there as it is in film.

 

Could you or anybody clarify this? Thanks.

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Jason, I was considering doing something similar to this for a scene I want to shoot, but dismissed it as impossible. It sounds like it might not be though.

 

If you don't mind, when you do shoot these scenes (assuming you do choose this method), could you tell me how everything turns out for you and the approximate cost of rental?

 

Thanks,

 

-Matt

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If you don't mind, when you do shoot these scenes (assuming you do choose this method), could you tell me how everything turns out for you and the approximate cost of rental?

 

Thanks,

 

-Matt

 

 

Sure Matt,

 

From the replys so far it seems that it might be an option as long as I am shooting MOS.

I just hope the rental price is within my very small budget.

 

Can anyone compare the noise levels between the gennys on these lights and lets say 2 smaller honda style gennys that would power 2 or 3 1k lights?

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As posted before, for me it worked perfect if you manage to control the sound.

My setup using a Light tower with four heads (check the gas the use to see color) was shot with F900 at 1/48 shutter at 23.98 fps. No flicker all perfect and if you get flicker most of this cameras have a clear scan option where you adjust the shutter to remove flicker and if the rest of your units are tungsten based you are fine flicker wise...

 

and the punch of that light tower was pretty amazing for its price/output etc relationship...

no I was shooting summer in Arizona and the sensitivity of the F900 was ridiculous high..I had to stop down the camera at night exteriors because it was seeing to much...

 

I would upload some still or videos but i can't because the movie is not finished...and I am going back for re shoots in a couple of week and may rent another light tower...

 

Best

M

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Miguel,

 

That sounds great, I think I am going to try and track down one of these lights! If you get some stills I would love to see them.

 

Maybe you could get a photo of what your setup looks like when you re-shoot. It might be helpful for others to see how you used them and what they look like.

 

How far away from the talent are you able to place the lights to get the nessesary light levels?

 

Would it be a possibility to get any usable audio while shooting, or is it a completely MOS situation.

Edited by Jason Banker
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They are loud really loud and it depends in the "ASA" of your video camera. When I was shooting the temp was really high and my ASA was really high too (high tempratureactually increase sensitivity in sensor...as I understand and has seen it change...) so you could put it away...now you need to realize is not a cine light, lenses etc..but they are powerful as hell...and you can get bigger or medium ones..etc...your best thing is to look for online info on lighting towers..and then call the guys..

anyway will look for images and let you know...but keep in mind the one i had was loud and far away but you can shield the generator with pads and so on..

M

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I just saw Children of men and there was a scene where those very same construction lights were used as practicals. The cinematographer documented the setup in American Cinematographer for last month. Its available as a free digital download.

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Look at the Inside Man..they used similar units but replaced the heads with Arri X lights I think...

 

 

Yes that is accurate. I worked on Inside Man and a lot of work went into replacing the light tower fixtures with the 1200 watt X lights since the light towers were being photgraphed. They also added a dense green glass to the front of the lights to emulate a green cast.

 

Best

 

Tim

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The Panasonic HVX 200 is rated at 320 ASA. So for night construction scenes you will have to pump in quite a bit of light. But fortunately for you, i think there will ba alot of places to hide lights in a construction set right? Aslo make sure you dont shoot the camera wide open. f2-f2.8 would be desirable. I have shot wide open on this camera in low light situations, and the blacks come out milky, and grainy. Not the effect i was after in that situation. Another side note, when shooting dark scenes, it's a good idea for you to shoot looking through the eye piece rather than the flip screen. The viewing angle of the flip screen is very narrow, and you will be looking at the image with the wrong exposure if the screen angle is not exact. A way around this is to look through the eye piece.

 

a while ago when i was shooting with this camera, i was shooting the NTSC version (in singapore that shoots PAL). I noticed the kino pulsing. This is easily fixed in camera.

 

Good luck on your shoot, and if you have any problem with the camera, you can contact me on this forum. I have learnt alot on the Panasonic HVX200 and the P2 format mainly through trial and error. Mostly error.

 

Ken Minehan

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Yes that is accurate. I worked on Inside Man and a lot of work went into replacing the light tower fixtures with the 1200 watt X lights since the light towers were being photgraphed. They also added a dense green glass to the front of the lights to emulate a green cast.

 

Best

 

Tim

 

While watching the film in the theatre, I noticed the light towers with the Arri fixtures immediately. Were the fixtures cables to a remote power source? One only has to drive past a large highway construction site at night to realize that the generators in these portable units are very noisy. I really can't see a film application for them, except as a work light.

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I've shot some 24P but not much and got the impression that it has to be at 1/48th sec. shutter

speed. Is that incorrect? I'm a little confused because I believe that in a film camera the shutter

is actually a material object spinning at a certain rate that is measured in both degrees and

exposure time (yes/no?) whereas the "shutter" in a video camera is a term for something

happening electronically involving exposure time but the "angle" option isn't there as it is in film.

 

Could you or anybody clarify this? Thanks.

 

 

There is no physical shutter, no spinning disk to block the gate, but there is usually a pin on CMOS chips, and a much more complicated circuit in CCDs that control the 'Shutter' speed. Basicly after the previous image has been cleared off the chips CCDs, a signal goes from high to low (1 to 0) when that pin is set to low, it keeps the CCD grounded, so any built up charge from light hitting it will in fact be pulled to ground. After a specific amount of time that pin goes from low to high, and the chip starts to build its charge based on the amount of light striking it. This effectivley reduces the amount of time the chip is exposed, yeilding similar results to a physical shutter in a film camera. There is no true 'angle' since its not a disk, but you can get relative angle with this formula A = 360 - ((E/T)* F * 360) where A is the angle, E is the electronic shutter time and T is the shutter base time, and F is the frame rate (1/48 sec @ 24fps is 1 = E, 48 = T, 24 = F)

 

Usually 24fps cameras try and have a 1/48th second shutter, but this is not consistent. Especially so with cameras that only mimic 24fps (cineframe, canons 24f, etc) Moreover, even if the default is 1/48th a second when in 24p mode (such as in the HVX-200) you still have the option of engaging the shutter at different lengths (or turning it off all together and have a 1/24sec exposure time per frame). Just because its in 24p doesn't mean you can't still switch on a 1/2000 sec shutter (aprox 355.7 degree shutter) or anything in between.

 

I remember I was in a club shooting for a band with the HVR-ZU1 in their cine-frame mode and got lots of flicker off the neon signs in the bar. I had to turn the shutter off all together to get the extra stop (bar owners only let me put one 80 w batt light to light a fairly large stage with 5 people on it)

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There is no physical shutter, no spinning disk to block the gate, but there is usually a pin on CMOS chips, and a much more complicated circuit in CCDs that control the 'Shutter' speed. Basicly after the previous image has been cleared off the chips CCDs, a signal goes from high to low (1 to 0) when that pin is set to low, it keeps the CCD grounded, so any built up charge from light hitting it will in fact be pulled to ground. After a specific amount of time that pin goes from low to high, and the chip starts to build its charge based on the amount of light striking it. This effectivley reduces the amount of time the chip is exposed, yeilding similar results to a physical shutter in a film camera. There is no true 'angle' since its not a disk, but you can get relative angle with this formula A = 360 - ((E/T)* F * 360) where A is the angle, E is the electronic shutter time and T is the shutter base time, and F is the frame rate (1/48 sec @ 24fps is 1 = E, 48 = T, 24 = F)

 

Usually 24fps cameras try and have a 1/48th second shutter, but this is not consistent. Especially so with cameras that only mimic 24fps (cineframe, canons 24f, etc) Moreover, even if the default is 1/48th a second when in 24p mode (such as in the HVX-200) you still have the option of engaging the shutter at different lengths (or turning it off all together and have a 1/24sec exposure time per frame). Just because its in 24p doesn't mean you can't still switch on a 1/2000 sec shutter (aprox 355.7 degree shutter) or anything in between.

 

I remember I was in a club shooting for a band with the HVR-ZU1 in their cine-frame mode and got lots of flicker off the neon signs in the bar. I had to turn the shutter off all together to get the extra stop (bar owners only let me put one 80 w batt light to light a fairly large stage with 5 people on it)

 

That's helpful. I'll be interested in experimenting with 24P at different lengths. Thanks.

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While watching the film in the theatre, I noticed the light towers with the Arri fixtures immediately. Were the fixtures cables to a remote power source? One only has to drive past a large highway construction site at night to realize that the generators in these portable units are very noisy. I really can't see a film application for them, except as a work light.

 

Only the heads were replaced and only film people would recognize a film light. 4-1200w ballasts were placed at the bottom of each light tower wherever it was moved or placed and powered from blimped film generators. When using construction light towers on a film set it is fairly common to bypass the power supply and onboard generator.

 

Best

 

Tim

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I have done behind the scenes work on "Extreme Makeover: Home Edition" and shot a lot under these lights with BetaSP. I usually balanced to 5600k on the camera shooting under them and did a little color correction in post. They read as a magenta, which was ok for the work I was doing since I was not trying to make them look like natural light. They can definitely be used. I am a little busy right now but I will try to post some stills a little later on today. Good luck with your shoot.

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