FORUMS: list search recent posts

Lighting for white background

COW Forums : Lighting Design

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
Bartek Bart
Lighting for white background
on Feb 22, 2017 at 11:46:42 am

Hi,

I need to make the video interview on white background. I made some shots, but I have some problems with lightning. The actor is to flat in my opinion, and also to gray. Later I'll put here sample, when I come home.

I use Savage Background made from cardboard, called super white (but it is not so super white at all..). Also I have 4 lights with umbrellas. Every umbrella has two bulbs- fluorescent, 85W, 5500K.

Two umbrellas are about 45 degrees from background and are lightning it (backlights). Also they are about 45 degrees down. One umbrella is very close to the actor, as a keylight, and the second one is as a fill light (far away). I was trying with headlight, but It didn't work.

Exposition is auto, BLC option is ON. White Balance is auto. My device is Canon XA10.

First question for now: Should the key light have more lights than 2 bulbs, how many?
Second question: Or maybe it would be better (and easier) to use a gray background?


Return to posts index

Vince Becquiot
Re: Lighting for white background
on Feb 22, 2017 at 4:33:49 pm
Last Edited By Vince Becquiot on Feb 22, 2017 at 4:34:59 pm

A roll of white paper on a background kit is the easiest solution for a white back, roll away when you're done.
Best of all, It's cheap.

I usually light flat with fluorescents (Kinos), just keep far enough to avoid hot spots. Either top and bottom, or sides.
You also might not want a completely white background, a slight gradient may be preferred.

For talent lighting, you definitely want a strong backlight. Clothing also matters, you want contrast, but the camera will be the limitation here. Absolutely white balance manually, with a card on the front/talent light. I also tend to add a little CTO gel on my front lights to avoid that grey look you are talking about.

Here's the typical Apple look:





Vince Becquiot

Indigo Live

San Francisco Bay Area


Return to posts index

Bartek Bart
Re: Lighting for white background
on Feb 22, 2017 at 8:26:29 pm

Hi thank you for respond. Here is the effect. The background should be white, the actor is gray, and he has shadow under the chin (but not this one in entire window, it is beacuse a program).



And here is the studio, fill light in the right, key in the left, back before the seat:



Return to posts index


Todd Terry
Re: Lighting for white background
on Feb 22, 2017 at 8:53:55 pm

I've had to do the "Apple look" countless times.... I haven't had to do it in a while now but back when it was in vogue a few years ago it seems like practically every week a client was needing that...

I did it practically with white seamless paper a few times, with good success although it was a fair bit of work to get it looking perfect. After a few times, I started doing them greenscreen instead, with much better success and much easier.

It was just so much easier to get that pure white perfectly uniform limbo background, and I could concentrate on just lighting the talent without having to be so meticulously concerned about the BG.

If you haven't considered that, you might want to give it a try.

I will note though, that usually white limbo backgrounds are not pure pure white... which can be a bit overpowering. Just for fun I sampled and tested the Apple video that Vince embedded... which appears to be pure screamin' white, but is actually 96% white. It's almost white, but not quite. I think when I've done it in the past I've ended up with background plates that were somewhere in the 90-95% white range, which looked good (and looked white).

T2

__________________________________
Todd Terry
Creative Director
Fantastic Plastic Entertainment, Inc.
fantasticplastic.com



Return to posts index

Bob Cole
Re: Lighting for white background
on Mar 1, 2017 at 12:57:39 am

I'm with Todd on this. White limbo is not as easy as it looks, and green screen (done properly) makes it easy to fine tune it in post. A white limbo background is just an extremely difficult thing to judge properly "live." Your concern about eyeglasses is understandable, but you will find that the "clear" part of the eyeglass will key beautifully, while the glasses' temples might actually present more of an issue.

Bob C


Return to posts index

Vince Becquiot
Re: Lighting for white background
on Feb 23, 2017 at 12:34:35 am

Here's what a proper exposure would look like: 11063_video.00000001.still001.png.zip

Your background and talent just need more light, especially the background. Umbrellas unfortunately really don't have much punch, I would recommend fluorescents for the background instead.

Make sure you manually set the iris on your camera.

Vince Becquiot

Indigo Live | Kaptis Media

San Francisco Bay Area


Return to posts index


Bartek Bart
Re: Lighting for white background
on Feb 23, 2017 at 9:00:28 am

I'm little bit afraid of green screen, it has other issues while cutting the subject, plus I think it could be much more difficult with talents glasses. I have a green screen sheet, could give a shot.

Okay do what do you think:
More bulbs to the background? Should be more distance between talent and the background (I'm afraid that more light in background will cause the reflection and the talent will be in "shadow").

Or more bulbs for key light and the background?


Return to posts index

Bill Davis
Re: Lighting for white background
on Feb 28, 2017 at 6:10:38 am

Bartek,

You need to balance 3 things here.

A) the light gathering capability of the camera you're using.
B) the amount of even light you can generate on background across the area where the talent is seen.
and C) the amount and nature of light you can generate on the talent - SEPARATE from the light on the background.

Typically, it's effective to set these types of scenes in 3 stages.

First, balance the camera sensitivity (Aperture and ISO sensitivity, typically) with the background using whatever lights it takes the get the background evenly exposed without noise or shadows.

Next bring in the talent and light them. Your goal is to expose them properly WITHOUT spilling too much extra light on the background and screwing up what you've already set up.

That's a bit of a trick. If you don't have ample space between the key light zone and the background zone - when you add key light to the talent, it's spill can mess up the background light field-

Step 3 is to REFINE the balance of the 3 elements until it's the best you can achieve.

3 things that have to work TOGETHER to make the shot a success.

Hope that helps.

Creator of XinTwo - http://www.xintwo.com
The shortest path to FCP X mastery.


Return to posts index

Bartek Bart
Re: Lighting for white background
on Mar 13, 2017 at 6:25:55 pm

Hey, thanks a lot. I've used your tips. Now we decided to use green box. Everything is better now, but the next issue has came.

Take a look for talents cheeks. There something with focus, it is more blurred. Especially on Full Screen. When screen is stable, I mean there is no move of talent, it is better.

I use Instat AutoFocus (tried with mono, but it was worse), the changes of settings doesn't help (we use F3.2 to F3.4; exposure 0 db to 3 db, shutter 1/50; temperature from 5400 K to 6000 K). Despite of the settings the blurred cheeks still occurs. What could I change? Too much light? Key light has 4 or 5 (we tried both settings) 5500K bulbs, 85W fluorescent (soft-boxed), two umbrellas on green screen, one head light (1 umbrella with 2 bulbs the same as in key light) and a fill light also 1 umbrella with two bulbs.

Here's the screenshot:


Return to posts index


Bill Davis
Re: Lighting for white background
on Mar 16, 2017 at 5:08:18 pm

Your depth of field is razor thin.

Try F8 or even F5.6 and the problem should go away.

You'll have to adjust your key light or reduce ISO to get the right exposure - but an aperture that wide open will give you nothing but grief on a live subject.

My 2 cents.

Creator of XinTwo - http://www.xintwo.com
The shortest path to FCP X mastery.


Return to posts index

Todd Terry
Re: Lighting for white background
on Mar 16, 2017 at 5:33:32 pm

Bill is right, its your wide iris that is causing your focus issues due to the shallow depth of field.

Me, I'm personally usually an uber-shallow DoF guy... I'll typically shoot f/1.3 or thereabouts, and yep depending on the distance or focal length that can give a DoF as shallow as an inch or less (fortunately both my usual AC and I are both reasonably good focus pullers, but it can still be a struggle). The key is eyeballs... if a subject's eyes are razor sharp in focus, then it gives the perception that the entire subject is in focus. You'll often see sharp eyes but soft noses and ears, but it still looks "right." But if a subject's eyeballs are even the tiniest bit soft, then that throws everything off.

But here's the thing, even if you like shallow depths of field like I do, usually there is no reason or need for them in most greenscreen situations. In fact, the opposite is true... the higher your f-stop and the deeper the depth of field, the sharper your edges will be on things like shoulders and hair and everything else you need to composite, giving you much cleaner keys without having to worry about edges and fringing and such nearly so much.

SO... just crank those f-stops up to at least f/.5.6 or so, and I think you'll be happy.

T2

__________________________________
Todd Terry
Creative Director
Fantastic Plastic Entertainment, Inc.
fantasticplastic.com



Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2017 CreativeCOW.net All Rights Reserved
[TOP]