Would like to record my face with a webcam on my desktop. I have a white wall with some light blue texture in front of my desk. Can I use that as a diffuser? I dont want to invest in a soft box or umbrella. I just tried it with my yellowish incandescent desk lamp, and seems ok except the yellow tone, so I plan to buy a white led spot light. What do you think? I can also put some white paper on the wall where the light hits the wall.
Attaching a drawing of my setup.
Your setup should be sufficient with the white paper on the wall and a neutral white (not warm, not cool) lamp. However, if you are going to chroma key out the back drop, your setup may cast your shadow onto it. Having a uniform backdrop is essential when using chroma key. You can do a couple things to reduce or eliminate shadows on a backdrop.
Add another light onto the left side of the webcam, aimed at paper on the wall, to help calm the shadows.
Move the backdrop back far enough so that the shadow is not cast onto it.
Get a light specifically for the backdrop. You can shine it onto your shadow to get rid of it, or diffuse it onto the entire surface to make it uniformly lit.
It will work after a fashion, but you'll get substantial reduction in light level when the light is reflected. In your application it may well be adequate.
If you wish to use a diffuser you do not need a formal or commercial one.
The paper that you intend stick on the wall could be used instead as a diffuser - it may prove too opaque, but it's easily tried.
Crumpled plastic bags , either white or clear, can be used to diffuse light effectively.
Add bags and increase crumpling to improve diffusion.
Light loss rises as diffusion effect improves, but probably less lossy than a paper reflector.
Absolutely! You're using this for a video setup, but it's common in still photography with strobes, where this technique is known as "bounce flash".
The caveat is that strobes — like from studio lighting, from hotshoe flashes, or even from the popup flash of a camera — are very short intense bursts of light. Your lamp, and probably even your spotlight, won't be as bright, and there won't be as much light to bounce around.
The other major downside is that it's hard to control. A softbox and other light modifiers are designed with control in mind, and can be positioned and aimed to get the effect you want. Moving the wall, by contrast, is more of a commitment. You can of course reposition your subject (in this case, yourself) and your light, but you can't do much with how the light scatters from the wall.
You, sir, are right on.
What I like about your propposed setup is the simplicity, and the effectivity. You'd save space, time and money and will be able to get very, very good results.
You can improve the reflactivity of your bounce difuser by choosing solid cardboard as white as possible. You can also use translucent paper with aluminum foil as a backing, or a mirror. The point is, transluent paper will let a fraction of the light go through, but it can be bounced back with somenthing highly reflective. A more solid piece of cardboard wont let light escape as much as thin paper.
AS other answhers say, propper lighting equipment will provide more control, and can be obtained on a budget, but they will also take a bit of space, wich can be out of your priorities if this recordings you want to make are not something you do extensively.
I'll be the first to comment that some white paints are "more white" than others - make sure to calibrate first, especially since you are capturing skin tones. Depending on your platform, you should have white balance tools for your webcam available to you. I've noticed, for example, that the auto white balance in software tends to calibrate for the blue from the monitor on whit screens as opposed to the more orange light that you will get from your spot.
Also, even though it's a bounce, you'll want to raise this slightly above eye-level so that you're not lit from below.
Otherwise - rock on!
