Lighting White Background

H

Heartfelt

Well-known member
I am shooting coporate stuff, we are newly into it and thus the budget is small. I am using my own cameras at this point for quality and working to
build a case to expand the budget. so far, so good with feedback.

I just ordered some cheaper softboxes and a hair light. I also grabbed a support and will pick up a roll of white paper. I am set with subject lighting
but have been waffling on the background lighting... in a budget mode. I originally thought of using 4 clamp lights with 42w 5000K bulbs. I just
realized today that that will not even begin to compete with my subject lighting as the soft boxes have 5 bulbs in each.

At present, I am shopping halogen work-lights and considering 2 on each side for a total of 4 500w heads.


Does it sound like I am on the right track for lighting that white background?

Thanks in advance for your reply.
Rob
 
In order for the background to look white you need the same exposure on it as on your subject. You're not pouring a lot of light on your subject, softboxes are quite lossy, and you won't need a lot on the background.

I'm not clear on the color temps, though. If your softboxes and hair light are tungsten at 3200K you will need the same for the background. The scoop lights you thought of would be fine but not with daylight bulbs.
 
Thanks for the reply.

The softboxes are fluorescents with 5 bulbs in each, totally 225w (true) at 5500K, per unit.
I will have one on each side of the subject. I understand the halogens are not colored properly and wondered how large a difference it would make and/or am I better with 4x45w/5500K CFL's or 2000w of halogen.

I seem to remember a 2:1 rule.... do I have it backwards? Is the SUBJECT supposed to be two
times brighter?

I appreciate the help!

Rob
 
Heartfelt said:
Thanks for the reply.

The softboxes are fluorescents with 5 bulbs in each, totally 225w (true) at 5500K, per unit.
I will have one on each side of the subject. I understand the halogens are not colored properly and wondered how large a difference it would make and/or am I better with 4x45w/5500K CFL's or 2000w of halogen.

I seem to remember a 2:1 rule.... do I have it backwards? Is the SUBJECT supposed to be two
times brighter?

I appreciate the help!

Rob
Click to expand...
Okay, no problem with color temp unless you use tungsten on the white then. The worklights are probably 2700K and they would look seriously yellow. You could gel them with CTB but you wouldn't get all the way to daylight as they are meant to correct 3200K up to 5600K.

I think the CFLs on the white would be fine. You can spill light from the softboxes onto the background and to adjust the amount of light on subject and background from the softboxes you can pan them so that you feather or waste their light as you turn them so they are not pointed straight at the subject. Obviously, you can move them in and out as well.

Not sure what lighting ratio you are thinking of. In greenscreen work you want the screen to be a stop or stop and a half less in intensity. One stop is double or half the light depending on which way you are going.

For a white background to look white it needs to have the same exposure as the subject. The best way to measure this is with an incident light meter. If the background is too bright it blows out and can cause haloing and flare, reducing contrast. If it is too dark it can look gray - not what you want.

There is no substitute for running tests. Do plenty.
 
slondon said:
Okay, no problem with color temp unless you use tungsten on the white then. The worklights are probably 2700K and they would look seriously yellow. You could gel them with CTB but you wouldn't get all the way to daylight as they are meant to correct 3200K up to 5600K.

I think the CFLs on the white would be fine. You can spill light from the softboxes onto the background and to adjust the amount of light on subject and background from the softboxes you can pan them so that you feather or waste their light as you turn them so they are not pointed straight at the subject. Obviously, you can move them in and out as well.

Not sure what lighting ratio you are thinking of. In greenscreen work you want the screen to be a stop or stop and a half less in intensity. One stop is double or half the light depending on which way you are going.

For a white background to look white it needs to have the same exposure as the subject. The best way to measure this is with an incident light meter. If the background is too bright it blows out and can cause haloing and flare, reducing contrast. If it is too dark it can look gray - not what you want.

There is no substitute for running tests. Do plenty.
Click to expand...


OK, it sounds like my first thinking may be the better which is additional CFL's on
stands with reflectors, bypassing halogens.

I have heard the terms "stops" and the terms f11, f16 and f22 and videos I saw suggest
subjects being lit at f11 and backgrounds being lit at f16 or f22 (dependeing upon the video).

I share that just to share perspective on where I am coming from. However, I would tend to
trust what I hear here as compared to "out there". So thanks for helping this audio guy in the
quest to crossing over.

I am learning that images can be equally fun and challenging as audio. This is a cool field.
 
Heartfelt said:
OK, it sounds like my first thinking may be the better which is additional CFL's on
stands with reflectors, bypassing halogens.

I have heard the terms "stops" and the terms f11, f16 and f22 and videos I saw suggest
subjects being lit at f11 and backgrounds being lit at f16 or f22 (dependeing upon the video).

I share that just to share perspective on where I am coming from. However, I would tend to
trust what I hear here as compared to "out there". So thanks for helping this audio guy in the
quest to crossing over.

I am learning that images can be equally fun and challenging as audio. This is a cool field.
Click to expand...

Very good. Yes, read up on exposure. You need it. Look up f-stops. If you have any trouble I'll answer your questions or give you a quick explanation. If you can deal with dB you'll find f-stops easier math and equally important.
 
Thanks a mill!

I will do that. In fact, being a member of lynda.com, I found they have a new tutorial on the basics of photography and it revolves around exposure.... good stuff.
 
Do you want the background to burn out or should it be at a lower value than your subject?

Be sure to go to a straight manual exposure setting on the camera, otherwise the auto iris will close down in response to the white and under expose the scene.
 
Razz16mm said:
Do you want the background to burn out or should it be at a lower value than your subject?

Be sure to go to a straight manual exposure setting on the camera, otherwise the auto iris will close down in response to the white and under expose the scene.
Click to expand...

Correct me if I am wrong but that may be the difference between what my thoughts (un-trained) were and slondon's. I can make either work and it would be nice to have the flexibility.

Am I right that the measurements for burnout are f11 -subject and f16 or f22 for background?
 
You must log in or register to reply here.
Back
Top