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Old December 20th, 2010, 01:04 AM   #1
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Backlight Advice: Arri or LED Fresnels or ?

I have 2 Diva 401's and 2 Barfly 200's and this has been working for 1-2 person shoots. Next month, I will be recording shows with 3-5 people; so, I started looking at adding lights and found an Arri 4-light kit with 2-150s & 2-300s. I also just found the Litepanels SolaENG 3 LED fresnel which is equal to tungsten 250w but only draws 30w. My main requirement is that everything is portable. The reason I find the LED fresnels appealing is in order to reduce the heat in the room, which is the main reason I went with Diva's in the first place.

For 3-5 people, would I need a fresnel on each person or is there a better option?

Thanks
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Old December 20th, 2010, 03:59 AM   #2
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It really depends on how the sitting arrangement, sometimes one light can back light 2 people (or more), although this may be more difficult with smaller lights.
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Old December 20th, 2010, 05:06 AM   #3
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I've been looking at the spec for the Litepanels SolaENG 3 LED fresnel. I'm deeply suspicious of any lighting manufacturer that don't provide proper specs - and this firm don't! Light output - look at the popular lighting manufacturers sites - for Fresnels we get a proper measured output at spot and flood, they specify at what point the light drops off - pretty important with Fresnels - and the blurb just is weird! My comments have been added to each line
Quote:
Proprietary Heat-Free LED technology
Produces bright, HD friendly light - HD friendly??
Integrated dimmer 100% to 0 with no noticeable color shift
Flicker-Free light output
Eco-Friendly - Uses up to 95% less energy
50,000+ hours of LED life
Highly Efficient
Lightweight
Instant restrike - LEDs do not strike at all, so why the comparison with HMI?
No ballast necessary - again, it's not a discharge source so why mention it
The only performance spec says
Quote:
Power: 30W (equiv. to 250W tungsten)
A 250W tungsten Fresnel can be very bright, or very dim depending on the design and beam angle - so without a measured output, this means nothing whatsoever. A 150W tungsten on spot can be brighter than a 650W on flood.

No doubt they are a useful tool, but the size suggests they are just good on-camera lights, and you wouldn't use them for normal lighting if you had better. The other thing is just the use of a Fresnel lens at all. The entire point of the Fresnel is the nice smooth light output, with less shadow and hard edges than a conventional open face or PC lensed spot. They drop off gently as the beam runs out and merge well with others for even cover - but the bigger the lens, the better they are. Even the smaller Arris are quite hard compared to their bigger brothers - a 3" Fresnel seems a strange choice as Fresnels in the smaller sizes are not as efficient. A bit of diffuser in front of the LEDs would have seemed simpler.
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Old December 20th, 2010, 07:16 AM   #4
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If you've got the cash, in your situation I would go for Dedolights. You'll get much more output (I also find this 250w comparison a bit uninformative) with far more control, an even beam and very little heat.

The unit with an in-built dimmer (I think it's the DLHM4) is about £500, built like a tank, replacement bulbs cost £5 every 5000 hours or so, the colour temperature doesn't change over time, and the unit will last you forever.
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Old December 20th, 2010, 10:54 AM   #5
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More to the point, do you necessarily want a fresnel unit for a backlight? What kind of distance to the subject will you be working with, and how are you hanging the units?

With lighting it's always a personal choice, but I don't generally like the look of hard backlight on an interview. If I do have to use a fresnel, I'll generally diffuse it in front of the barn doors.

For single person interviews, in recent past I used a Litepanel Mini on a c-stand arm, just above the person's head. Very portable, Easy to position, and dimmable for different subjects. Might not be appropriate for a multi-person setup as the falloff is pretty significant. Many interesting options out there these days. I've been looking at the color-correct, dimmable LED tapes lately--you could stretch a length between two c-stands and create a very soft backlight across multiple people--and talk about portable!
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Old December 20th, 2010, 04:17 PM   #6
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I have used Kino's for backlight but I want more control, and I have used Arri fresnel 150s before and really liked them. I should have also mentioned that my kit will eventually be used for greenscreen next year (but only 1-2 people). My studio is 20' wide by 26' deep with a 12' wide background against the front wall next to the door for most shows. However, the 12' wide Bg is not wide enough for 4-5 people so we will build a Bg that goes a few feet along the left wall and curves to the front wall in order to give us ample room for 3 camera angles.

My first inclination was for an 8' Kino mounted on the ceiling for backlight but that is neither portable nor controllable.

To answer your questions:

Distance and how am I hanging them: a few feet behind the talent who are sitting; either on c-stands on each side for the outside people and with arms extending for the inside people; or use a combination with 2 hanging from the drop ceiling support. I would use the flags to shape and simple diffusion paper to soften.

One idea I have is to use the Arri 150s for the people on the outside who are closest and the 300s for the inside people. My problem is whether I need 4 lights for 4 people and keeping the heat down.

I have an option to use the room next to our studio which is at least 30' wide by 50'+ deep, but that would be a major PITA because all the cables from our server room would need to be re-run in addition to carpeting and installing a drop ceiling.

For the Dedo's, how are they less heat - I thought they are tungsten.
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Old December 21st, 2010, 05:42 AM   #7
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They are 24v 150w. Not as cold as leds but more colour accurate and kick out a lot less heat than an Arri Junior. Also they are not so delicate when hot. You can move a Dedo around quite firmly when it's switched on, do that with a 150 Junior and you'll blow the bulb.
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Old December 22nd, 2010, 10:57 AM   #8
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The fresnels will give you control in that you can isolate them on each person, which is desirable when you have a thick head of black hair next to a bald person, or a platinum blonde. However the small size of the 150 lens will give you more of a hard line or even hot spot on the person's head. If you diffuse it to spread the effect, you are throwing away the control and effectively turning the unit back into a non-fresnel, so you could have gone with something like a small Lowel light at that point.

You will definitely want to be able to remotely dim the units to adjust the level of backlight on camera; any tungsten unit can have an outboard dimmer connected inline, but the color temperature will shift as it is dimmed. As you know from using Kinos there are a number of dimmable fluorescents, and all good quality LED fixtures can be dimmed. Make sure to select ones that have the dimming function on the ballast or inline rather than on the head for obvious reasons (there are versions of Dedos that have it either way).

A unit that I like and own is the Gyoury light (gyoury.com), similar to the Diva, but the ballast can be removed from the back of the head and remoted, making the unit light in weight (easy to hang), dimmable and has egg crates to control the output. Makes a great backlight. Not inexpensive in this day and age of cheap knockoffs (which it isn't) however.
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Old December 22nd, 2010, 03:27 PM   #9
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Thanks guys.

I had to place an order today including a greenscreen so I went with 2 Arri 300's plus their accessories and also diffusion paper and magenta filters. For now, I will make do with the 4 Kino's and 2 Arri's.
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