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10k Fresnel


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#1 John Allen

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Posted 20 September 2008 - 10:12 AM

Ok so I'm looking into buying an 100 amp tungsten 10k fresnel. So my question is this, do I need to find a 10kw generator that has an 100 amp plug, or can I find an 100 amp adapter to bring it down to 50 amps. And if I can do that, where do I find adapters at. Also, if I can't where can I find an 100 amp generator with at least 10kw output, which I for some reason can't find anywhere.
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#2 Paul Bruening

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Posted 20 September 2008 - 12:27 PM

Hey John,

You can get those things dirt-cheap, nowadays. Lamps can be a little pricey but still cheaper than HMI lamps. The big tungsten cans are not much good for anything but big, night exteriors. You have to gel too much of the footcandles out for daylight use. They're too big and too hot for anything but the largest interiors.

This is just opinion, but I'd pass on it. It's a whopping pain to find juice, run big feeds for them, and rig them. Ask yourself, "Can I light large night exteriors another way or do I HAVE to have these big cans?"
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#3 John Allen

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Posted 20 September 2008 - 04:19 PM

Hey thanks for replying paul.

The reason why I was going to get one was cause I need to light for a forest at night. And I was going for the same kind of effect that harry potter had in the dark forest scene in the 1st movie. Ummm, I guess the big reason was that I really wanted a strong moon stream of light for the wide. Which naturally I thought I would probably need a lot of light. I saw that most hmi's are much more pricey than just getting a tungsten and throwing a gel over for the moon. And the great thing is that the 10k I found was only like $600, which is pretty cheap in my opinion at least. Anyway, a lot of the film is in the forest, so it would be nice to have it look great. For the close ups it'll be easy to make it look good with just some 2k's, but it's just the wide that I'm worried about, which I don't think 2k's will be quite strong enough.

Also, when you said "those are dirt cheap nowadays", were you refuring to the 100 amp generators or the lamps?

Again thanks for replying. :)
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#4 Matthew Buick

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Posted 20 September 2008 - 05:17 PM

Hi, before I start, I'm 17 too, and I really love the look of your film. Must make sure I see it. :)


Right, from what I gather powering a 10k lamp would be a bit of a pain in the bum, frankly. What I would do if I were you is just day-for-night it, there'd be a lot less hassle and it can look fairly convincing if you practice before hand. Just underexpose as much as you can and tungsten balance the camera, If you need to see the sky a Graduated ND should cover it up. If you don't like the blueness then some half-CTO over the lens would correct that, but reduce underexposure accordingly. Midday on an overcast day would probably be best.

The important thing at our age is just enjoy yourself. Don't worry about the big lights just yet. Have fun! ;)

Wow! I'm mispelling everything tonight. I must really have overdone it earlier.
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#5 John Allen

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Posted 21 September 2008 - 02:46 AM

Hi Matt, thanks for the comment. And yes I'll try and put it up on Vimeo when we finish. :)

I originally was planning on just doing DFN for it, but now that I've had more experience I've found that doing DFN can look ok, I guess. But I just don't really like it. When I think of night, I think of light areas and true black areas, if you understand. I mean a real contrast between light and dark, where as DFN you don't have control over it. I've found that it ends up looking just really bland. I'm not saying that nobody can do it, but I just don't like the look it gives. Oh also, I have this mindset that it's kinda like cheating. I don't know why I think that, but I'm just weird like that. lol

Also, I'm glad you like to have fun during a shoot, and that's totally fine. And I totally like to have fun too, but I've gotten to the point I think where I am not just being a DP for fun, I now strive for excellence, even if it means I my feel like crap when day is done. And I love shooting and it's really fun, it's just I now shoot on how it looks, and if it's not looking the way I visualize it then I take the extra step, and it doesn't matter to me if it takes hard work.

So I guess I'm saying that I've already decided that I'm using a 10k, because I know that's what I need. But I want to know, does anyone know if there are like some adapters that I can get so I can hook up the 100 amp plug into a 50 amp socket?

I hope I didn't affend you. I just wanted you to know that it's totally cool if you want to just have fun at it. But I like to have fun, but now it's work, great work, but it's work. And I'm trying to do the best I can, cause I'm trying to work for a full ride through film school. So my lighting has to look pretty darn good. I maybe 17, but I try and compare my films with the best. Cause, I won't get to where I want to be unless I learn to as good as the best. So I'm sorry if you took it wrong. :(

Thanks comment though, it's great have others input.
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#6 John Allen

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Posted 21 September 2008 - 02:51 AM

Oh and now that I think about it, I probably should have put it in the lighting forum after all, cause I'm not actually asking for advice about whether I should use a 10k or not. I don't know why I ended up putting it in this one. :blink:
So my bad. lol
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#7 Walter Graff

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Posted 21 September 2008 - 07:30 AM

"A 10k generator"

You'd be maxing out your generator with this fixture, so don't expect everything to run smoothly over time. You'll more than likely end up blowing the breaker constantly or having the gen shut down. In fact you'll probably never be able to power up the fixture without it blowing. You need to have padding with a generator. Try a 12-15k surge generator for 10k light.


"does anyone know if there are like some adapters that I can get so I can hook up the 100 amp plug into a 50 amp socket"

You wouldn't want to do that. If you are talking about one of those portable 10k generators, you will be in trouble. It does not have the correct connection (let alone the wattage necessary) for the current needed. Plus the small 10k+ generators make about 85 dbs of noise. Hope you have lots of cable or the films MOS. Best to get someone who knows what they are doing.
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#8 John Allen

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Posted 21 September 2008 - 02:06 PM

Thank you that's exactly what I was wondering about. So thank you for letting me know about that, before I found out the hard way. :unsure:
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#9 Andrew Koch

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Posted 21 September 2008 - 09:35 PM

You definitely posted in the correct forum. The lighting forum is more for professional inquiries. I do not mean any disrespect by saying that. It's just better to post in Students and First Time Filmmakers when you are starting out because you will get answers more tailored to your needs.

You must understand that you are not supposed to plug something larger into a smaller socket, even if you can find and adaptor that will make the physical connection possible. With power and cable, you are always limited to the smallest variable. For example, lets say you have a 200 Amp genny. if you have 4/0 cable which is rated for a maximum of 400 Amps per leg and you have 3 hot legs, this means you have cable that will support up to 1200 Amps total. But you still only have a maximum of 200 Amps because of the generator. Lets switch it around. Lets say you have a 1200 Amp genny and you are connecting your distribution box with 5 wire banded. The cable is rated for 150 (maybe 170, but lets just say 150 for easier math) giving you a total of 450Amps Maximum. Unless you are doing multiple runs out of the generator, the maximum you will get out of that generator is 450 Amps.

For your example, a 10K draws 83.3 Amps. This is obviously more than 50 Amps. With a 50 AMP outlet, but you would be limited to a 5K (which draws 41.67 Amps), however a 5K uses a 60Amp plug, so you would need a 60Amp outlet.

Before you spend a lot of money, you might want to read up on this stuff (Set Lighting Technicians Handbook by Harry C. Box) and consider renting. Although I'm not sure if you can rent if you are under 18.

If you need a lot of light on a tight budget, you might want to consider working with par 64 lights rather than fresnels. a nine light maxibrute has way more output than a fresnel and draws less power (but you would need to diffuse it to mask the multiple sources) Single par units run off of house power or a put put genny and can be used as slashes of light to light up backgrounds of night exteriors.

Make sure you study up on all of this so that you can be safe. Since you are 17, there could be liability and insurance issues with all of this so make sure you do all of this with adult supervision and clearance and remember safety first.
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#10 John Allen

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Posted 21 September 2008 - 11:50 PM

Yeah thanks, the amps thing was like the only thing I really couldn't find an explanation for, so thanks for clearing that up. Pretty much the only information about amps I found gave me the impression that it was more of a plug size not so much with the wattage. But I think I understand now. I've worked with lights that are 50 amps and lower, but never an 100 amp so that kind of boggled me. Anyway, thank you for the info, and I will definetly check that book out, it sounds good.

Oh and I'll be 18 when we shoot. Just if your wondering. :)
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#11 JD Hartman

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Posted 22 September 2008 - 01:50 PM

The Harry Box book is good starting point. You might also want to read a book on industrial/commercial electrical work. What you are dealing with here is the Power formula, P (watts) = I (Amperes) * E (voltage). To determine the amperage draw of your 10K, 10,000 (watts)/120 (volts) = 83.33 amps. So it need to be connected to a cable terminated with a 100A Bates. Another consideration would be voltage drop of the cable at the (single run) distance from the generator or power source. Yet another fomula found in the Box book or any good Electricians text.
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#12 Paul Bruening

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Posted 22 September 2008 - 02:08 PM

Hey John,

As you might have determined, Harry's book is like a bible to many of us. As you read through Harry's book, you'll start to get the idea that big cans need big wires, big sources and short feed distances. You are heading into a monumental headache with this approach. Sure, if you can afford it, why not do it? I love that big scene, big can, fully lit look. But, does the project really justify all that? Could you get the scene in another way? Oh, Brother used that old school, dashes of light on some of its night exteriors and was delightful (please, forgive the pun).
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#13 John Allen

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Posted 22 September 2008 - 03:44 PM

Yeah I actually was going to say that I came up with another idea. Instead of the 10k, I thought I might put up 2k's around. And that will also add depth in the forest. Which the 2k fresnels are only 20 amp edisons. I've drawn up some lighting diagrams which I'll see if I can post them soon.

The film will be fully funded, so money isn't a real issue, take that back, it always is, but I mean we have enough money for lighting. And it would be nice for the shoots to go a little easier as long as it looks right. Come to think of it I usually always get a little stressed at shoots anyway. lol

Yeah for DP's electronics is a great thing to learn. :)
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#14 Matthew Buick

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Posted 25 September 2008 - 07:02 AM

Also, I'm glad you like to have fun during a shoot, and that's totally fine. And I totally like to have fun too, but I've gotten to the point I think where I am not just being a DP for fun, I now strive for excellence, even if it means I my feel like crap when day is done. And I love shooting and it's really fun, it's just I now shoot on how it looks, and if it's not looking the way I visualize it then I take the extra step, and it doesn't matter to me if it takes hard work.

But I like to have fun, but now it's work, great work, but it's work. And I'm trying to do the best I can, cause I'm trying to work for a full ride through film school. So my lighting has to look pretty darn good. I maybe 17, but I try and compare my films with the best. Cause, I won't get to where I want to be unless I learn to as good as the best. So I'm sorry if you took it wrong. :(


Hi.

I think I made myself misunderstood. Cinematography/Photography is more than just fun for me. It's the blood in my veins. And I do too strive to be the best I can be. Please don't take me to be some wishy-washy person who takes the occasional shot, and doesn't know what half of the manual functions in his camera do. Also, I'm not in the least bit offended, so don't worry. ;)

For me cinematography is something innate and personal, I find that if I lose sight of why I'm passionate then I become much less productive. If I'm happy and working at a relaxed pace then I'm at my best.

Colour plays a huge role in how I perceive light, I love strong expressionistic colours in my work. For me DFN works perfectly if I can get either a soft toplight or a strong sidelight. I'm lucky that when I balance my HV30 to Tungsten it comes out with a terrific shade of pastel blue that suits me down to the ground. I much prefer in-camera to any sort of software.

Salutations! :P
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#15 John Allen

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Posted 25 September 2008 - 08:34 PM

Ok, now I get you. I seriously thought you were saying that a cinematographer is someone who just throws a camera on a tripod and starts shooting things. So, now that I understand you I'm very glad that your not like that. Lately, ppl have been having the impression that I just shoot stuff to put on youtube and stuff, which has been getting a little annoying, uno.

Anyway, that's really cool that you like DFN. I think it really depends on what look your going for. So, good luck with all that your doing and if you ever post pics or a video of your stuff let me know. And I'll be sure to let you know when I put "In the Silence" on Vimeo.

Salutations to you too. :)
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The Slider

Metropolis Post

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Media Blackout - Custom Cables and AKS

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Broadcast Solutions Inc

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Technodolly

Wooden Camera

Abel Cine

Tai Audio

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