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Old July 5th, 2007, 04:26 PM   #1
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On using reflectors

Hello,
I am going to shoot in an overcast/cloudy outdoor location with abandoned buildings around and there is no way to get electricity there, maybe only sunguns. A generator is not an option.

Is it possible to do it only with reflectors, let's say DIY white foam boards with metal foil on one side? The scene can and should be a bit gloomy (hence the need for a cloud cover), but I want to avoid a grainy picture.

What are the physical limitations of using reflectors, what is your experience?

Many thanks!
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Old July 5th, 2007, 05:34 PM   #2
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I love using hard reflectors when the conditions are right, but without direct sunlight reflectors are useless, there's nothing there to reflect.

You might be better off renting a cheap generator from a tool rental company and go with lights.
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Old July 5th, 2007, 08:10 PM   #3
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If possible take your camera out there ahead of time & shoot some test footage.

You might be surprised how much light there really is even on an overcast day. When there is cloud cover, we percieve the world as dark, but actually much of the light is still getting through, after bouncing around in the clouds.

It depends how sensetive your camera is, but lots of cameras these days are sensetive enough to shoot on cloudy days without using light amplification, which is what will cause the grainyness you fear.
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Old July 5th, 2007, 11:29 PM   #4
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Thank you for your replies, I'll try to do a test footage,
and I have Canon XH A1.

Renting a generator is not an option because we don't want to get noticed by making loud noises, so we'll hike to the location.

If there won't be enough light, I'm considering pointing sunguns to reflectors. :)
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Old July 6th, 2007, 11:18 AM   #5
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The sun is extremely powerful (even through clouds)... you will have enough light unless you are shooting close to sunrise/sunset. That is unless you are shooting inside the building.

2- If the day is overcast, the overall lighting will be very flat and reflectors won't do much. If the sun is poking through the clouds then they will do something... but then you run into the situation where lighting fluctuates depending on whether the clouds are blocking the sun or not.

You could try doing negative fill... there's a picture of that at efplighting.com
http://efplighting.com/?Lighting_int...ick_Interviews

But whatever you use to block light has to be very big, proportional to the framing of the shot.

3- The problem with sunguns is that their color temperature is around 3200k, which will be very warm compared to sunlight. You can gel your light but then that cuts the light output and the light is not powerful enough.

4- Try going out and seeing how the natural light works for you... if you have diffused light coming through a window that can be a beautiful look (depending on what you're going for). Place the subjects in interesting light.
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Old July 6th, 2007, 05:42 PM   #6
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you could also use rechargable HID daylight lamps... I have 4 that make great daylight fills... last about 70 mins on a charge and will run off 12v source as well.... cost about $65-95 usd.

Sam's club sells ( $65 ) a power on board HID rechargable spot ( 22 million candle power ) that is 6000k and a cri above 85.... I have 4 of them right now and they are very narrow beam but make great little hmi daylight spots. They last about 70 mins on a charge, but will run off a 12V source for longer. here's a link to a video I shot useing 1 of the HID spots from behind.... http://www.witzke-studio.com/hd/dyingindiana.html

and here's a review by someone into lights....
http://ledmuseum.candlepower.us/eighth/powhid.htm
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Old July 6th, 2007, 09:29 PM   #7
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Quote:
Originally Posted by Andris Krastins View Post
Hello,
I am going to shoot in an overcast/cloudy outdoor location with abandoned buildings around and there is no way to get electricity there, maybe only sunguns. A generator is not an option.
Many thanks!

Sveiks Tautas Bralis !

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Old July 7th, 2007, 12:07 AM   #8
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Christopher, the site with the review of those lights has a graph that shows a significant green spike and their pictures all have a green cast compared to sunlight in the same shot. Actually, it looks like they have both a blue and green spike but no red to balance things out. I noticed in your music video that the beams of light have a bluish corona which I initially thought was a result of daylight spots being used along with tungsten key lights. Now, I'm not so sure it is just a color temperature issue. How do things look to you with these lights and daylight combined?
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Old July 7th, 2007, 09:38 AM   #9
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They do start up a bit green....but need a few mins to get up to full brightness, and level color.... but intercutting with daylight they look good.

with the music video... the key lights were tungsten floods... so the spot looks blue.... but the added color helped adds to the stage look it think.

here's some clips of the light in use....
http://www.witzke-studio.com/hd/hidfoot.mov

the raw coffe beans in the bag are just 1 hid bounced off a white foamcore.

the roasting dudes is a combo of HID and 6 bank daylight flo.

the espresso pour is a combo of HID and daylight window....

to be honest.... I really have not had any problems with the color or CRI rating of these HID spots..... no special grading needed.... ad add a little nattress bleach bypass to my footage sometimes... but just for a more contrasty look ( which I like )

oh... and one thing I do like about them, is that if you slow down the footage, you don't get the flicker problem that you get with flo. ( so I've noticed )
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Old July 7th, 2007, 09:57 AM   #10
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Nice work Christopher. Hey anybody can have an opinion, even if they have never had any experience, your lighting is subtle and transparent and yet makes the scene pop. By the way I have one of thoses $65 hid lights too. They make quite a stream of daylight coming in a window. . . wow.
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Old July 7th, 2007, 06:15 PM   #11
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yep... they work for me.... and the fact that you can do a scene in the woods at dusk/dawn miles from a wall tap makes me giddy.

I've been tempted to dismantle a few and put them in a china ball... battery and all.... now if only I could get them to float without using stands...hehe

To be honest... I don't know why the link about the light shows pics so green... I've used the lights with my Canon 5D at daylight setting and it fills great.. no noticeable color shift.....
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Old July 7th, 2007, 06:26 PM   #12
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Someone said that the sungun is only 3200K. Not true. There are several HMI sunguns for daylight use. Frezzi makes one for instance.

http://www.adorama.com/FZ92809.html

There are others too. A sungun is really nothing more than a par that can operate off batteries. No reason to mystify it. A par can be HMI or halogen technology. Open face or with a very clear safety lens. A flashlight is a par configuration by the way ;-). So is a car headlight. And a par is just an abbreviated spotlight without the fancy plano-convex lens and long focusing mechanism. Both pars and spotlights have the same ellipsoidal reflector with a bulb peaking through the middle type configuration. Just like a flashlight or car headlight.

You can see here in this website, they have a Joker 200 and then a "Sungun 200" by K5600. Really the same fixture...

http://www.birnsandsawyer.com/cgibin...hting&start=10

The main difference is battery operation. There's another HMI sungun there by LTM too.

I've gotta say though, this is one useful little find Christopher. You can't beat the price for sure. Everyone ought to have this little light in their kit. I think the best name for this device is not "spotlight" though as it really doesn't qualify as that since it doesn't have the fancy lens. It really is a metal halide, daylight sungun or battery powered par for our purposes.
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Old July 7th, 2007, 06:29 PM   #13
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Quote:
Originally Posted by Christopher Witzke View Post
yep... they work for me.... and the fact that you can do a scene in the woods at dusk/dawn miles from a wall tap makes me giddy.

I've been tempted to dismantle a few and put them in a china ball... battery and all.... now if only I could get them to float without using stands...hehe

To be honest... I don't know why the link about the light shows pics so green... I've used the lights with my Canon 5D at daylight setting and it fills great.. no noticeable color shift.....
The link shows the pic's green because the photographer didn't understand how to use his white balance. If you're going to use them in a China ball, why not use a more powerful version like a 70w or 150w. It's not so much harder to put one of those together. Then you have a poor man's spacelight. If you had a makeshift green screen stage, I can't think of a more even lighting over the entire area than a few china balls with 150w metal halide's in them. 13000 lumens (or so) each is roughly the equivalent of a bunch of 650w bulbs which would otherwise require a pretty beefy china ball.
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Old July 7th, 2007, 07:35 PM   #14
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"The link shows the pic's green because the photographer didn't understand how to use his white balance."

Note that I said, "their pictures all have a green cast compared to sunlight in the same shot".

The lights look green compared to the sun and no amount of white balancing can deal with two different colors. I suspect that what Christopher said about them needing time to warm up may be the issue. It is clear that the colors look fine in his videos. I agree that the blue corona in the music video makes the spotlights more interesting. I figured it was due to the key being tungsten. Regardless of any color issues, these lights look rather handy. Someone just needs to figure out how to put a 5/8" socket on the yoke. :)
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Old July 7th, 2007, 10:19 PM   #15
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HID bulbs need about 1 to 5 minutes to be stable for sure. The ones I've been using actually stabilize in a minute or so. HID really can make the best sungun when you consider the lumens per watt and necessity to keep battery draw to a minimum to increase watt hour life. They've got such great throw too.

At some point I hope to revisit this subject with a Cool Lights 70 or 150w sungun as I really am impressed with the price performance ratio of those bulbs. I'm learning a bit about batteries right now too as I've been working on an LED project in my extra time. Looks like Lithium Polymers / Lithium Ion are the techology to use for these kinds of things to keep them small and lightweight. Pair a small 70 or 150w par fixture with a high watt hour battery and recharger and you've really got something to put an LED panel to shame.
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