We've covered the Av setting in a previous blog post, so now it's time to go over the Tv setting. If you haven't read the Av post, it wouldn't hurt to check it out, because there are some basics there that aren't duplicated in this post.
Tv is like Av in that it allows you to manually select one setting while letting the camera select the other. Tv is Shutter Priority mode. You select the shutter speed, and the camera chooses an appropriate aperture or f-stop.
This setting is useful when you specifically want to either stop motion or exaggerate it. If you're shooting a sporting event, for example, you'll want a fast shutter speed in order to "freeze" the players in action. Alternatively, if you're going for that "silky water" effect, you'll want a much slower shutter speed to blur the motion of the water.
A few things to keep in mind. High shutter speeds require a lot of light. This presents a challenge when shooting indoor sports, for example. Compensate when necessary by raising the ISO. (We'll cover ISO in a future post.) Slow shutter speeds generally require a tripod. Image Stabilization lenses have come a long way in reducing camera shake, but as a general rule, you should use a tripod for any exposure slower than 1/30 second.
Your mission, should you choose to accept it, is to find a moving object (kids and pets make great moving subjects.) Switch your camera to Tv mode, and start at 1/30 of a second. Take a picture, then go to a faster shutter speed… Say, 1/60 second. Take note of the f-stop your camera chooses. Keep raising the shutter speed until an exposure isn't possible (due to available light.) Review the images to give yourself an idea on how shutter speed affects motion in your photos. Next, on a cloudy day, grab your tripod and seek out a waterfall or fast moving creek, or even the ocean. Start with a 1-second exposure and move to slower shutter speeds from there. Most cameras will limit you to a 30-second exposure on the Tv setting. As a side-note, when you're working with slower shutter speeds, if your camera has a 2-second timer, use it. The timer is great for reducing shake from pressing the shutter button.
As always, I'd love to see your pictures. Feel free to tweet them to me: @danhedrick.
Quick question--would it be helpful to you if I put together a shared Evernote notebook containing some of these beginning tips? Let me know in the comments.
Next up, ISO.