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#1 Zulkifli Yusof

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Posted 12 July 2007 - 10:34 AM

Hi all

I dont know if anyone has ever done this or would recommend doing this, but I'm thinking of doing the following and I need advice:

Using 3 redheads without barndoors, putting them on stands close together (in a triangular formation) and shining them through a 216 frame at full flood. Subject (human) is 1.5m away from lights and wall is 1m behind subject.

Question 1: Will it create multiple shadows on the wall or will it seem like it was lit by a single source?
Question 2: If I move the setup further back and put a "window" between the light setup and subject, will the redheads be enough to give well-defined rays of light or do I need a stronger source?
Question 3: Should I put the "window" further away from the source or closer to the source to get well-defined rays of light?

Thanks.
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#2 John Holland

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Posted 12 July 2007 - 11:37 AM

what you shooting film? video ? HD ? helps to know , 1.5m lamps to subject is close , further away is better , just depends what stop you want to shoot at and as i said before how much the camera if video etc or film the stock needs to get a good exposure .
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#3 Zulkifli Yusof

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Posted 12 July 2007 - 01:24 PM

Oh, I'm using either the XL2 or XL-H1, depends on budget and camera availability.
Either way, I'm definitely making use of its 20X zoom and for all setups, I'm shooting within the lens normal to tele range and as wide aperture as possible (f2-2.8).

The shooting location is ideal for that purpose and I have no problems backing up the camera and lights should the need arises. What I want to achieve with the setup is a past-noon sun forming visible rays of light through the window. With budget to keep in mind, I would like to know if I can do without an HMI package and make do with redheads/blondies etc instead.

Hope that makes it clearer!

Thanks
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#4 John Holland

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Posted 12 July 2007 - 01:36 PM

If you want rays of light wont get that from what you said before thats ok for lighting the person will have to use harder light for sunlight effect cant seeing needing hmi 's .
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#5 Ralph Keyser

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Posted 12 July 2007 - 03:08 PM

Question 1: Will it create multiple shadows on the wall or will it seem like it was lit by a single source?
Question 2: If I move the setup further back and put a "window" between the light setup and subject, will the redheads be enough to give well-defined rays of light or do I need a stronger source?
Question 3: Should I put the "window" further away from the source or closer to the source to get well-defined rays of light?

Thanks.


Pushing the light from the 3 redheads through something like a 4x4 frame of 216 will get you a single soft source. You'll want enough distance to let the beam from each light fill the frame of 216. So, you won't see multiple shadows from this setup. (As a complete aside, is it still called a 4 by in parts of the world smart enough to use the metric system?)

I'm assuming that by "well-defined rays of light", you mean sharp shadows. Light hard enough to show sharp shadows will also get you multiple shadows from the individual light souces. The 216 set-up above will not get you hard enough light to show sharp shadows.
Even if you wanted to see the light itself (by introducing smoke into the scene), that softer source will not get you a traditional "beam of light" effect in smoke.

HMI's are popular because they are very efficient sources of daylight temperature light. You can achive the same effect with tungsten lights, but the amount of power you may have to draw (and the amount of heat you generate) may be excessive.
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#6 Kevin Zanit

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Posted 12 July 2007 - 04:44 PM

I use more than one light through one frame of diffusion all the time. It helps to create a more "wrappy" soft source.
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#7 Zulkifli Yusof

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Posted 13 July 2007 - 11:52 AM

Thanks for the replies guys. They were definitely helpful.

Qn 1: So, sticking with a tungsten package, how should I modify my setup to achieve the beam of light effect through the windows?
Qn 2: Is it necessary to introduce "smoke" into the setup for the beam of light effect or can I simply get away with it by just using harder sources?
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#8 Jonathan Bowerbank

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Posted 13 July 2007 - 06:35 PM

Thanks for the replies guys. They were definitely helpful.

Qn 1: So, sticking with a tungsten package, how should I modify my setup to achieve the beam of light effect through the windows?
Qn 2: Is it necessary to introduce "smoke" into the setup for the beam of light effect or can I simply get away with it by just using harder sources?


Without smoke you won't get any beams at all, no matter how hard the source is. You'll also want to shoot it relatively low key so there's something dark in the background behind the beams and they appear more defined.

Since you're only working with a few redheads, you'll probably want to light for a wider iris, 2.0 or lower. Place the lights far from the windows so your inverse square strength indoors is wider and more consistent and rate the light coming in from outside a couple of stops above key.

Out of curiosity, where should this light be coming from in the real world? Sunlight? Streetlight? Hopefully not moonlight :/
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#9 Zulkifli Yusof

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Posted 14 July 2007 - 09:10 AM

Without smoke you won't get any beams at all, no matter how hard the source is. You'll also want to shoot it relatively low key so there's something dark in the background behind the beams and they appear more defined.


Ok, got it.

Place the lights far from the windows so your inverse square strength indoors is wider and more consistent and rate the light coming in from outside a couple of stops above key.


I just lost you with the inverse square thing. Care to explain in different terms? Sorry about that :P

Out of curiosity, where should this light be coming from in the real world? Sunlight? Streetlight? Hopefully not moonlight :/


It's sunlight. I mentioned 2 posts back that I wanna achieve a past-noon sun streaming in.

Thanks
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#10 Jonathan Bowerbank

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Posted 15 July 2007 - 03:36 AM

Just as an example, here's a quick and not at all carefully calculate text example of what I'm talking about:


Light< -----1ft f/5.6-----2ft f/4----------4ft f/2.8--------------------8ft f/2, etc, etc, etc...


You lose light intensity as you move away, but the amount of a light's drop off gets less acute the further you move away from it.

So, if you move the light far enough away,, you'll have an even beam of light coming through the window, instead of a beam that starts out hot then fades off quickly.

Sorry, missed the part about the past-noon thing :)
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#11 Michael Nash

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Posted 15 July 2007 - 03:46 PM

Light< -----1ft f/5.6-----2ft f/4----------4ft f/2.8--------------------8ft f/2, etc, etc, etc...


You lose two stops every time you double the distance.
http://www.geofflawr..._square_law.htm
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#12 Jonathan Bowerbank

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Posted 15 July 2007 - 03:54 PM

You lose two stops every time you double the distance.


There you go

thanks! :)
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#13 Joseph Zizzo

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Posted 15 July 2007 - 07:40 PM

for the effect you're going for, you really want to use a single fresnel. ideally a big fresnel, so you can, as jonathan said quite accurately, back the light up and even out the beam. this concept is essential, in my view, for creating a sunlight effect, and a fresnel has just the right kind of photmetrics to imitate sunlight, especially at full flood. and you definitely want to use some sort of window effect.

if you have the power/budget for 3 redheads, you have power for a mole-richardson studio 2k fresnel (not a baby junior). if you can get your hands on one, they are much cheaper than hmi's. for a small fresnel, it'll give you a ton of light, and it'll be of the exact quality that you are looking for. actually, a 1.2 hmi fresnel (not a par) would be a good choice, too, and would also be pretty cheap, since everyone tends to work with pars when using small hmi's. if you can afford a 5k fresnel, that would be ideal, because you can back the light up even more. but if not, then go with the 2k, or the 1.2 hmi fresnel...

if you follow jonathan's other excellent suggestions, using smoke and keeping the bg down, amd maybe gel the lights with lee "wheat" (763?) you'll achive an excellent late-afternoon effect.

have fun!
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#14 Ken Minehan

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Posted 15 July 2007 - 11:22 PM

Hi Zul. Maybe you can tell me where your location is. I'm in Singapore so i may know it.

If you want a defined beam of sunlight you will probaby want to take away the diffusion. I realise you want to use diffusion to blend 3 lights in to one, but with the diffused lights 1.5m from the subject, i dont think you will much of a beam. If you are using the a small tungsten kit for budget reasons, then maybe you can get in touch with Bert, from Berts Lighting house. He rents out a lighting truck for video shoots. Will cost you $500.00 SDG per day. This kit has all the small tungsten frenels that you will need, 1.2 HMI. 575 HMI, alot of clamps, tracks Dolly, Kino etc. I use this kit for mist of my shoots. If you want to add extra lights, like 2.5k HMi, 4k HMi, 10k HMi, he will give you a good deal. Just give him a call and see what he says. Also he is a good contact to have too.

So back to your question, i think to achieve the look you want, i think you will need a bigger light source further back and smoked.

Hope it helps
Ken Minehan
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#15 Jonathan Bowerbank

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Posted 16 July 2007 - 02:06 AM

If you want a defined beam of sunlight you will probaby want to take away the diffusion. I realise you want to use diffusion to blend 3 lights in to one, but with the diffused lights 1.5m from the subject, i dont think you will much of a beam.


Good suggestions, but while we're on the topic of diffusion, check out a past thread discussing the method of using a "soft topper".

If you don't think the beam effect will work, perhaps another approach could be this method: http://www.cinematog...;hl=soft topper
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#16 Kevin Zanit

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Posted 16 July 2007 - 02:49 AM

I just did a music video that I wanted various shafts of light in a bar/ club scene. It doesn't have a ton of baring on what you are trying to do sunlight wise, but it does show the beam effect of some various sources with smoke (or in this case haze, I prefer to use the DF50 haze machine over a smoke machine).

This image shows the difference between the beam of 1k PAR cans (w/ MFL globes) and 1.2k HMI PARs (with a narrow lens). These pictures are terrible, in camera the beams are correctly exposed, and very blue:
par_can_1_2_par.jpg
Another shot showing two 1.2k PARs:
1_2_par_2.jpg

And you also asked about multi source through one frame, here are 3 PAR cans going through a 6x6 half grid, aimed through the frame to hit different parts of the dance area:
multi_par.jpg


Kevin Zanit
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#17 Alex Wuijts

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Posted 16 July 2007 - 04:41 AM

As a complete aside, is it still called a 4 by in parts of the world smart enough to use the metric system?)


For the sets I've worked on in the Netherlands: a 4x4 is called a one-twenty frame or just a big frame. A 6x6 is a 2x2, a 12x12 is a 4x4 and a 20x20 is a 6x6.
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#18 Bill Totolo

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Posted 16 July 2007 - 08:59 AM

Why not soft light the subject (with a couple of your red heads through diffusion as you suggested)
then hardlight your b/g with your remaining unit? Put a window frame in front of it for your effect.
Add haze as suggested by the other members and gel to taste.
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#19 Chad Stockfleth

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Posted 16 July 2007 - 10:57 AM

My suggestion is the same as Bill's. Use two of your redheads through the diff. and keep the third one hard. Break it up with a window cookie or some boards.
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