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#1 Vedran Rupich

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Posted 23 May 2008 - 06:53 AM

I'm about to shoot a video where the subject will stand in front of a wall, which will have a 1/3 inch diameter hole every 4 inches, forming this grid. the background will be a 1/3 inch thick plywood plate, painted black.
To the point, I want the the light streaks coming through the holes to be "laser-like" and occasiannly hitting the lens, i planned to use smoke in order to get the volumetrics, but i wonder if not hte light will disperse all over te place, as i would like it to be fairly concentrated?
Would a HMI do the trick, or should I go for a xenon? The overall scene will be pretty low-key.

Any suggestions?
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#2 Chris Keth

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Posted 23 May 2008 - 06:55 PM

An HMI would do the trick, as would a fresnel fixture. You'll want to be full flood (widest lens if the HMI is a PAR fixture) and have the fixture backed up from the drilled-board some to get the most defined pattern.
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#3 Michael Nash

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Posted 23 May 2008 - 07:14 PM

I'm about to shoot a video where the subject will stand in front of a wall, which will have a 1/3 inch diameter hole every 4 inches, forming this grid. the background will be a 1/3 inch thick plywood plate, painted black.


You mean like pegboard?

Use a small point source for the narrowest beams. The farther away the light is from the wall, narrower and more parallel the shafts of light will be. If you can't get enough distance or brightness with a single unit, consider using multiple smaller units next to each other like Source 4's; taking care not to let their beams overlap.
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#4 Vedran Rupich

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Posted 28 May 2008 - 04:25 AM

Great,Thanks! I'll go with HMI's, think that'll work.
Also, i wonder if i use a ringlight? how much light can i squeeze out of it? The camera setup is rated perhaps 50 ISO?
How far back can i be to get a decent exposure? I was planing on using a 50mm lens, framing my subject in a medium shot.
how much can one get out of a kino kamio ringlight? Is it possible to expose?

regards

Edited by Vedran Rupich, 28 May 2008 - 04:26 AM.

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#5 Michael Nash

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Posted 28 May 2008 - 04:36 AM

Usually small ringlights like the KinoFlo Kamio are only good for fill-level light, close up. At 50 ASA and 7-10 feet you're going to need something much brighter.
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#6 Vedran Rupich

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Posted 28 May 2008 - 05:17 AM

allright, i figured it would be too small.
Any recommendations of what to use? something brighter but still keeping the "ringlight feel"?
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#7 Eric H

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Posted 28 May 2008 - 07:38 AM

allright, i figured it would be too small.
Any recommendations of what to use? something brighter but still keeping the "ringlight feel"?




How wide of a shot are you planning?

Eric
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#8 Vedran Rupich

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Posted 28 May 2008 - 07:48 AM

How wide of a shot are you planning?

Eric



Well, the wider I can go the more safe I'll feel. But If i can use it for my midshots atleast, 50mm FOV cropping the waist.

Then on my wide shots with the 24mm, I'll figure leaving the fixture on but adding some other sources in.
Will the Litepanels Ringlight Cinema do the trick?
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#9 David Rakoczy

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Posted 28 May 2008 - 07:49 AM

allright, i figured it would be too small.
Any recommendations of what to use? something brighter but still keeping the "ringlight feel"?



Build your own 4ft Ring Lite and load it with ph213s (250w). A half a sheet of plywood, showcard, porcelain sockets, wire, a plug, zip screws and a staple gun are all you need. It helps to paint the plywood with reflector white. Mine works great using 1000h paper on it and 1/4 CTB brings it to 3200k. Have extra bulbs on hand as they will burn out at about 3 hrs.

Cut vent traps!!!!!!!!

Enjoy it on this shoot and rent it out on the next....

btw.. the 'Holes' and 'Placement ' on the board you mentioned seem very very small to me....

Edited by David Rakoczy, 28 May 2008 - 07:50 AM.

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#10 Eric H

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Posted 28 May 2008 - 08:27 AM

Well, the wider I can go the more safe I'll feel. But If i can use it for my midshots atleast, 50mm FOV cropping the waist.

Then on my wide shots with the 24mm, I'll figure leaving the fixture on but adding some other sources in.
Will the Litepanels Ringlight Cinema do the trick?




I take it you are shooting on video? which camera? lay down all the specifics if you have them....it'll be easier to form a solution. You mentioned 50 ASA rated setup....even on film that'll mean a lot of light will be needed at 7-10 feet. I shot a group of 8 -10 people in 2 rows at 10 feet away, I held a 3 shot most of the time. Using an old home made ring light and shooting on 500ASA I barely had a 2.8, maybe less(if I recall correctly). I just made a new ring light from Ikea LED strips........Used 32 strips in a wagon wheel pattern. I allowed for a 6" round hole in the middle of a piece of foamcore. the color temp was roughly a bit more than daylight.....and with my meter set for 500ASA at 24/25 fps....was reading a 4/5.6 at 4 feet.....I am planning to add another round of LED's to boost the output. I use this light and it cost me about 240 euros to build.
this config won't answer your requirements though.
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#11 Eric H

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Posted 28 May 2008 - 08:40 AM

Here's a picture of the most recent ringlight I made....

Ikea_ring_lightWEB.jpg


the two small holes are for the Arri 19mm support rods.

Eric
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#12 Vedran Rupich

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Posted 28 May 2008 - 09:29 AM

yeah I figured I'll perhaps need a special solution.
The setup is aproximately 50 ISO, its an hvx with a mini35. worth mentioning is that i dont have the fastest primes, and besides, the more i can approach a f/5.6 the happier I'll be, even though that is wishful thinking.

Eric that setup is cool. Do you think it would be bright enough for my purpose.
Besides the talent in this hot is dark skinned, making exposure even tougher.

The Litepanels Ringlight Cinema looks rugged and bright? any input on that?

David your solution sounds as if it can produce enough light, I just feel somewhat uncomfortable with the DIY with so much heat that they will be generating.


cheers
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#13 Hal Smith

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Posted 28 May 2008 - 09:47 AM

Use a Forstner bit to drill the holes in the plywood, otherwise you'll get holes with splintered edges.

http://en.wikipedia....it#Forstner_bit
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#14 Eric H

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Posted 28 May 2008 - 10:37 AM

I would say that my set up will not allow enough light for you. Although, I shoot 95% film, I have used the HVX a lot, both with the Mini35 adaptor and without. I don't like the adaptor very much in certain situations.....yours being one of them...I use the Schneider Optics 2x teleconverter when I want a narrow DoF. works great and gives you loads more stop....look on my website for the Nuon Solar Race spot...I shot that entirely on the HVX with the 2x teleconverter, .75 WA adaptor and the fisheye adaptor....every shot was with the hvx and schneider set up.
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#15 David Rakoczy

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Posted 28 May 2008 - 01:20 PM

[quote name='Vedran Rupich' date='May 28 2008, 08:29 AM' post='234049']

<Eric that setup is cool. Do you think it would be bright enough for my purpose.>

Yes it is... but no it isn't. A 4ft Ringlite loaded with 18-20 ph213 bulbs using no Diffusion will get you 4 - 5.6 at 7-10ft at 50asa. That will also buy you some cushion to go high speed.. and you can always use Nds at 24fps etc... You will then need something even BIGGER for the back-'effect'-light thru the Board.... your mentioning Zenon is the right direction. I would think a 4kPar at the very least. On the other hand, maybe the Zenon might not cover the amount of Backliight you need and you want to go 12k Par.....

Go BIG!
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#16 Eric H

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Posted 28 May 2008 - 04:27 PM

[/quote]

<Eric that setup is cool. Do you think it would be bright enough for my purpose.>

Yes it is... but no it isn't. A 4ft Ringlite loaded with 18-20 ph213 bulbs using no Diffusion will get you 4 - 5.6 at 7-10ft at 50asa. That will also buy you some cushion to go high speed.. and you can always use Nds at 24fps etc... You will then need something even BIGGER for the back-'effect'-light thru the Board.... your mentioning Zenon is the right direction. I would think a 4kPar at the very least. On the other hand, maybe the Zenon might not cover the amount of Backliight you need and you want to go 12k Par.....

Go BIG!
[/quote]


David, you are absolutely right..........be prepared to shoot high speed so you gonna need even more stop.
Eric
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#17 David Rakoczy

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Posted 28 May 2008 - 08:32 PM

Correction.. I just counted mine and it has only 12 sockets... so 12 - 15 250w bulbs (globes) will be plenty, not 18 - 20. Cut vents and you won't have an over heating problem at all, especially if you go without diffusion which you will probably want to do to get that stop you mentioned.

A huge thing to consider is setting this up so your Key (Front) Light does not wash out the 'Smoke' you are using to create those little beams. You will need a lot of separation between the Talent and the Board so your Key Light does not wash out that effect you are trying to create.

With regard to extra 'punch'.. this took me a long time to learn and even longer to get used to but now I go in big so I am ready to go high speed... even if it is not in the Script or even on the Director's mind. If the Director wants to go high speed I want to be ready and a lot of the times it is me making the suggestion if I think it will look cool... or fit the story at that moment etc... I have no problem shooting thru a ND3 or 6 or 9 all day so when we want to ramp it up all I have to do is change a Filter and let it rip. For Exteriors this is normal operating procedure but even when going 'inside' and Lighting I like to have the extra punch.... it always comes in handy when you can do it.

btw.. Eric, beautiful work!!!!!! Love your reel!!!!!

Edited by David Rakoczy, 28 May 2008 - 08:33 PM.

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