Re: Soft LED Lighting Question

[ectobuilder]

Re: Soft LED Lighting Question

If I wanted to fill a 10ft x 10ft room with 1000 lux of soft light from a single diffused source what kind of fixtures and modifier would I need.

Assumptions:
- there are no windows in the room
- you can assume daylight OR tungsten
- the light source can be put in one corner and when metering the kitty corner, we get 1000 lux.

 

[hscully]

It really depends on what you're lighting and what for. Is this a hypothetical or a real shot?

 

[ectobuilder]

It really depends on what you're lighting and what for. Is this a hypothetical or a real shot?

Is a shot I'm hoping to do. In terms of what we are lighting, we are lighting a 10ft x 10ft room so that any object or person in the room will be lit softly with a minimum of 1000 Lux.

This will allow us to shoot any where in the room knowing what our minimum lux would be, and we can vary down from there. Also, being a single point source, it would make the scene look more natural, as if there was a giant window in the room.

 

[DPStewart]

You may need more than just a typical 1'x1' panel because that might not be enough throw after diffusion.

I am going to guess you are asking for LED suggestions because you need to keep heat to a minimum. Correct me if I'm wrong.

Also: do you need it to be battery power-able?

Here is the big-dog: Area48 remote phosphor panel. Powerful, fantastic color, battery capable and will still be bright after additional diffusion.
It's also mad-expensive. Does that matter?

http://www.bbslighting.com/products/area-48-soft-remote-phosphor



Here is a cheap LED panel that just 'might' be strong enough:

http://www.amazon.com/Aputure®-Amaran-Video-Light-light/dp/B00N1RK5U4



If you can use AC power you can also consider a Kino-style fluorescent light. The really don't get hot at all compared to tungsten, they use less current, and they are soft by nature.

Here's a decent Kino Diva clone for half the price: Just add a $7 1/4 minus green gel on the front to remedy any green spikes, or spend $900 on the Kino Diva which has bulbs that don't need that (Kino True Match bulbs). These fixtures are smaller than they often appear in the pictures - about 23"x10" and 4" deep.

http://www.bhphotovideo.com/c/produ...AWD_Fluorescent_Video_Light.html/prm/alsVwDtl

 

[paulears]

If you want 1000Lx everywhere, then you need multiple fixtures spread around the room. Directionality will be important. so w white ceiling you can bounce off will be very useful, but getting light at a certain level everywhere means at least 4 cardinal point positions for sources, else, certain directions will be darker.

 

[Josh Bass]

I may be misunderstanding but I think the premise is flawed: if you're simulating a window, the light would be coming strongly from one direction, bouncing off everything else. A person in the room would be quite a bit brighter on one side, the other side lit by the bounce.

 

[morgan_moore]

The thing about window light.. the sun coming in is that the intensity is constant...

Distance to source = a million miles or at the other end of the room a million miles and 3 meters.

With a source at the window the intensity will drop off with the inverse square law.

Distance to source = 10cm through to 3m

S

 

[paulears]

... and window light is hard, unless it's an overcast day, which won't be right. Sun=shadows? I thought he meant there were no windows, so just an unlit box?

 

[Greg_E]

What about multiple panels stacked together? The size of the array should provide a softening effect since the array will be physically larger than most objects so the light can wrap around the object. Maybe 8 1x1 panels stacked in a 2x4 array which would give you the approximate size of a window. That said I'm not sure if this would give you the 1000 lux at the far corner. And as said above, the difference near to far will be pretty extreme from inverse square law.

 

[silyn]

I don't think it's possible.

 

[nyvz]

If I wanted to fill a 10ft x 10ft room with 1000 lux of soft light from a single diffused source what kind of fixtures and modifier would I need.

Assumptions:
- there are no windows in the room
- you can assume daylight OR tungsten
- the light source can be put in one corner and when metering the kitty corner, we get 1000 lux.

If the other end of the 10x10' room is 1000lux and the only light is on the other side of the room, the center of the room will be around 250lux, right? Is that what you are trying to achieve? How big do you need the soft diffused source to be? Does the source have to be diffused as in utilizing diffusion or just a naturaly diffuse source and how diffuse? For example 4 Kino Celeb 400's stacked together would do it according to their photometrics, and the light source would be ~4x4', though you might have trouble fitting them all in the corner of a 10x10' room especially with them pointed into the opposite corner...