Anyone ever use what I call a DOF chart? Here's one of mine:
I have one for each of my lenses. (FYI, I print them out in B&W on 8.5 X 11 paper, so they appear basically reversed from the above picture. PLUS, the positioning of the f-stops is messed up in this transfer to JPEG format.) I use them to determine what will REALLY be in focus. Sure, I have a nice, adjustable 7X Wista loupe for the groundglass, but a DOF chart with a rangefinder is more accurate.
I use an Ideal Rangefinder which is very small and light.
Other companies have made them as well, from Kodak to Leica. They can be purchased for next to nothing -- well, maybe not the Leicas. My Ideal model focuses from 2.5 feet to infinity, an is adjustable should that be necessary. No battery needed. For closer focusing, I use a tape measure.
I have never seen DOF graphs available commercial, but perhaps I have not looked hard enough because I made my own. I started with a circle of confusion of my choice and wrote a program for each lens in Turbo Pascal and then plotted the results in Harvard Graphics on logarthmic distance scales. On the scene, I choose the near and far points that I want in acceptable focus. Then I use the rangefinder to determine their exact distance from the film. I then check the DOF chart to determine what the f-stop needs to be to achieve that -- without any tilts or swings. But tilting and swinging is always an option if I need to use them, but I'll still place my focusing in the center of the range -- again with the help of the rangefinder.
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