I shoot in Av mode a lot. Av mode (or A mode for Nikon users) is Aperture Priority mode. In Av mode, you set the camera’s ISO & aperture and the camera picks the shutter speed. Once you have an understanding of how the exposure triangle works, Av mode starts to make sense & becomes another tool to use in addition to Manual mode.
- I almost always shoot with as wide an aperture as possible; not going above 2.8 unless absolutely necessary. So that third of the triangle is set.
- A shutter speed of 125 is the absolute lowest I’ll consider with a kid; 200 is much safer as a minimum. So there’s the second third of the triangle & where my adjusting starts.
- If my camera wants to shoot a super-slow shutter speed (& I’m already at as low of a number as possible on my aperture) I increase the ISO. The ISO needs to be high enough to allow the camera to choose a shutter speed of 125-20 or higher.
This is not Auto. This is not a fool-proof, thoughtless way of shooting. If you’re not getting the results you want, you might have to stop shooting, look back through your shots, check your exposure & settings and switch to manual. You’ll learn to gauge a situation & decide if it’s best to shoot in manual without even trying Av.
I shoot in Av if I know I’ll be moving vs. the subject moving. If I want to turn as a kid moves around, especially indoors, I need to have a range of acceptable settings in mind & shoot accordingly.
It’s important to remember that when set to spot metering, your camera uses the whole inner circle to meter, paying the most attention to the center box. So if 1/2 of the space filling that circle is super-bright and 1/2 of it is dark, your camera has to guess what the shutter speed should be. It will likely choose a much faster shutter speed than you want. Here’s an example:
1) I decided as Ellie was running up to the house from the bus to take a quick shot. I love seeing her dash off the bus with a huge smile, so happy to be home. The backlight was so strong that she ended up way too dark (underexposed):
Settings: 1/1250 (super-fast/high, creating a dark image); f/2.8 (maxed out for the lens I have; as wide as possible), ISO 800 (set from whatever I was shooting beforehand)
2) In an effort to correct my exposure, I got close in order to fill the frame with her skin/face & lock exposure so the next shot I took was better exposed:
Settings: 1/125 (uh oh, you can see blur in her backpack & coat; 1/125 is probably too slow here), f/2.8; ISO 800
3) Once she threw her crap on the floor (as opposed to hanging it up), I asked her if she had gas & got a great smile. By then, she was several feet away from the door & facing it, creating totally a different lighting situation from when she walked in. So my center circle was almost completely filled by her face (with a good portion of her face being her gums here!) & my center box (center focal point) right at the inside corner of the eye on my right:
Settings: 1/320, f/2.8, ISO 800
Final product (edited in LR3):
This takes practice. A lot of practice. First practice on a cooperative subject (diet Coke cans & Barbies work well) & then try it on your kids. Use the same lighting situation as you did when you were practicing. Remember how much the lighting changed between these shots. Just a slight turn or step away will create a change in light. I’ve shot my kids a lot in front of this door. And when I say “a lot”, I mean…a whole lot. I’d guess that well over 1/2 of our pictures inside our home are in front of this door. It’s a good, reliable spot. Don’t underestimate a good, reliable spot when you’re learning!
And it’s no substitute for mastering manual shooting. It’s a good tool to have. I used the term “crutch” in the title & that’s what it is but let’s consider moving children to be the sprained ankle making the crutch necessary. This wasn’t an instance in which I wanted to give direction or interrupt the “entry –> crap on floor –> hey how was your day” process by asking her to stop while I adjust settings.
This is the method I teach once a camera owner learns which buttons & dials do what.
I’d love it if you stopped by the Michiana Mamarazzi forum & posted a few of your practice shots!