Thursday, December 27, 2007

Holiday Pictures with Bounce (Flash)

Man, I wish I had actually read Strobist on Monday. The Christmas Day game plan is brilliant! But of course, I read about it today instead of when it can actually do me some good.

In case you don't know, the game plan I refer to is to set up two strobes the night before to give nice lighting in the early morning hours of Christmas Day. Essentially, it is a cross-lighting technique using bounced light in two corners of the room, giving you uniform lighting and the independence to shoot anywhere. Of course, the results post gives more details of the lighting set-up, examples, and description.

Me, I just used standard old bounce flash... on camera (for shame!).

If wedding photographers have been using it forever, I suppose it can't be all bad.

Bounce Flash Basics

The basic gist of bounce flash is shown in the amazing diagram I drew in PSP below. Includes color! (and yes, I am available to draw stick figures for pay)

Aim the flash head up at the ceiling to produce a large area of diffuse light (just like an umbrella or soft-box). That light then illuminates the entire scene. To change the location of the light, just change the angle of the flash.

For instance, in the image at left, I had it aimed too far forward, causing a bright spot on the ceiling behind the tree. Oops :) Even then, note that the huge light fire-hose that is a Sunpak 383 manages to get enough light on my kids to see their expressions. As usual, all the images in this post can be clicked on to see them larger.

When I adjusted the flash to aim directly above me, it produced the image at right. This is the down side of bounce flash... Since there is only one light source, you're pretty much always going to have light drop-off somewhere in the image. Typically, closer objects will be brighter, so it is advantageous make the closest object in the frame your subject.

Using a Bounce Card

In the diagram, the red object on the flash is a bounce card to produce a catch light in the subjects' eyes. If you don't know, a bounce card is attached to the back of the flash (away from the subject) to reflect a little bit of light very brightly toward the subject. While I don't have any close-ups to show you the idea, you can get the point from the near 100% crop of my wife and daughter below. Notice they both have bright spots in their eyes to give them a twinkle and an added bit of life.

If you look at the light from the point of view of the subject you'll see a bright spot from the bounce card. Which, I actually did thanks to my wife, because we needed to document me opening my mother-in-law's present.

To really see the light distribution from the subject's perspective, check out the reflection in the (fingerprint covered) TV:

Bright, small light right at the camera, and a large diffuse light from the ceiling bounce.

My Experiences

My first session was Christmas Eve when a friend's family came for dinner (sadly, they're leaving the area, and we just dropped them at the airport yesterday). They have four kids who are really good friends with our kids, and I wanted to get some candids of them playing to help them remember each other. So, slap the ol' Sunpak 383 on the camera, pop it into manual, spend a minute or two monkeying with settings, then try to get some candid shots before my kids cover their faces (apparently, they've been my subjects way too many times).

I'm not going to post any of these shots though, because I didn't get permission to stick them on the web.

The second session was Christmas morning and I used what I learned the night before to get a lot more keepers, like the image that opened this post. So what did I learn?

  • Shoot RAW. Since I could boost or decrease the exposure up to three stops in each direction, I didn't need to nail exposure each time (more info on shooting RAW). Very useful since I was moving around the house and each room gave slightly exposure values.
  • Don't skimp on power. Groups of children will rarely stay in the same plane (willingly, at least). As a result, I used an aperture of F/8 most of the time requiring at least half-power on the Sunpak at ISO 200.
  • Keep the ISO low. As tempting as it is to use a higher ISO and use less flash, I found I needed to boost the brightness a lot in post processing. After all, overexposing could blow highlights, while underexposing is easier to recover from. Boosting exposure is essentially raising the ISO, so start with a lower ISO to keep noise manageable.
  • Use a bounce card. My bounce card was a white(ish) post-it my wife had written someone's number on, rubber banded to the flash head. Cheap, but it worked great.
  • Remember to change the flash direction when you do portrait oriented shots. This was actually a big annoyance, and one of the reasons the fixed crosslighting method is superior if you know you'll be working in a single room. Often, I saw a pleasing composition in portrait orientation, but by the time I swiveled the flash the subjects had already run away to put on more princess dresses. Of course, if you have white walls, you can just bounce it off the wall (although the lighting will come from a different direction).
  • Make sure you have white ceilings :)
Ok, that covers it. Next year, I'll set up some fixed strobes, but the experience I got using bounce flash this year was well worth it!

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