>>2870654>What good is a tape measure?Say you're shooting a portrait and you want a really blurred background.
Set up on a tripod and compose your shot in 'A' aperture priority mode.
Run a tape measure from camera to subject and beyond.
Open widest aperture, in this example we'll say f/1.4
Focus on subject (keep the tape measure in frame) take your test shot.
Reviewing the test shot, look at the numbers on the tape measure to see where your focus falls off.
Make changes aperture and taking more test shots. As you go to slower and slower apertures, you'll see the DOF increase on your tape measure.
I find this tremendously helpful with getting that blurred background cinematic-look in my portraits because I can pinpoint exactly where my model needs to be, set my marks, and not have to worry about whether I'm going to lose focus due to DOF. After enough practice, you'll know your lens well enough that you won't need it - but it's very helpful for learning.
One more thing.
Measuring and marking DOF with tape measure is a good way to position a model just in focus, then frame her with objects (like tree limbs) in foreground and background that will be blurred. You like bokeh, don't you?
