Sunday, May 27, 2007

Non-Industrial Light & Magic

I splurged a little this week.

Since about the beginning of the year, I've been running into a wall when it comes to getting more creative with the photographs I take. The two most common problems being:
  1. I need more light. Either that, or I'm stuck with using really wide apertures and leaving only a thin sliver of the image in focus.
  2. I need to control available light. Either there's too much spill from the available light source which clutters up the image, or it's simply coming in from the wrong direction.
So many hours of online research and several trips to Keeble and Shuchat later, I'm now the proud owner of:
  • 1 Olympus FL-36 flash
  • 2 PocketWizard Plus IIs transceivers (to remotely trigger said FL-36)
  • 1 Westcott 43" silver umbrella
  • 1 Manfrotto light stand (over 6', but collapses to 19")
Add to this an assortment of DIY snoots and gridspots (created out of the boxes that all of the above loot arrived in) and one trigger-happy amateur photographer, and you've got the makings of a joyous long weekend.

First experiment: Creating soft light for a headshot. The difference between soft and hard light is all in the shadow. Actually, it's all in the transition from light to shadow. And that's all about "apparant light-source size", which is just a fancy name for the size of the light source relative to the size of the object being illuminated. Take a gander at the following diagram, where the white bars on the left represent light sources that are illuminating the circular object on the right:

In each case, imagine you're an ant moving along the surface of the object (see arrow), you first hit a point at which the far edge of the light source starts to go out of view. From now on the amount of light hitting the surface gets progressively less until the near edge also goes out of view leaving the object completely dark. What the top and bottom diagrams show is the difference in the distance between the first and second point when the size of the light source is changed relative to the object. The smoother the transition, the softer the light. Here are a couple of examples which demonstrate the quality of soft light.

The first two are using the flash shot into the umbrella from about 3 feet away, while the third uses the flash bounced off the ceiling to create an even bigger apparent source.

Second experiment: Controlling light spread. This is where the snoot comes in handy. Using it to restrict the spread of the beam of light, you can get it to illuminate exactly what you want without scattering photons willy-nilly and contaminating the scene. I've always wanted to create those funky smoke photographs you see once in a while, and having a nice tight beam of light coming in from the side allowed me to capture these beauties:

Happiness :)


saturn air jam said...

nice article!
now, if only I had some more money...

John Mathieu said...

Thanks for the article. I see that you went to Keeble and Shuchat...I used to go there quite a bit when I lived in Palo Alto and actually went to school with one of the Shuchat daughters.

Got many strobists at google? I work for Microsoft and we have quite few :)

Ruth said...

Rock ON Aaron! Found you from your link in the Strobist comments on Lighting 102. I was always wondering WHY big lights get softer shadows, but it didn't click until I saw your diagram.

Aaron said...

John: We have a photography mailing list at Google which is really active. I haven't checked, but I'm sure a significant chunk of them are Strobist readers :)

Ruth: Glad the diagram helped!

Anonymous said...

Thank you so much for this.

P.S: Got to here from here.

slurp812 said...

A picture, or in this case a diagram is worth a thousand words. Thanks!

Oli said...

Hi, I'm currently blogging about the lighting102 course (in German: and although it's not really hard to understand, I think the diagram might help a lot of people to understand where these soft shadows come from, thus I borrowed your image (and linked to your site). Hope you don't mind - if you do, please drop me a note and I'll immediately remove the image.

Guillaume MENANT said...

Hello Aaron, I'm currently writing an article on my L102 experiments (in French) and i'm planning to use your image about the transition from light to shadow. Can you please get me your clearance (if it's the correct word :D) ?

My website is located here :

Thanks !

Jeff Eppinette said...

Now I understand why the transition area varies from small versus large light sources! Eight years later and this diagram is still enlightening people. Thanks!