Originally posted by rustynail925 How do you compute the hyperfocal distance?

If your lens has aperture-distance scales inscribed on it -- almost all older primes, some older zooms -- the lens does the computation for you. I explained that in post #3 above. I also shoot film in some old folders that aren't marked, so I carry the little KODAK MASTER PHOTOGUIDE (available in many dusty thrift shops) which includes a DOF computer for 47-52mm, 70-80mm, 100-105mm, and 137-152mm. If I use an unmarked zoom that's beyond those ranges, I'm just S.O.L. (surely out of luck).

As for your 115/8 picture: I look in the Photoguide, extrapolate a little, and calc that if you hyperfocus at 50 ft, your DOF will be 25 ft to infinity. So f/8 is too wide - and that's working backwards, anyway. The front edge of your picture looks to be about 10 feet away, maybe less. How to get DOF of 10 feet (3m) to infinity?

**Argh, that Online DOF Calculator looks to be WAY off!** Depth of field - Wikipedia, the free encyclopedia has some nasty-looking equations that I'll ignore. The Photoguide calculator suggests f/22, hyperfocus 18 ft, DOF 9 ft to infinity. A couple 90-100mm lenses (and some old zooms set to 115mm) say it can't be done - best DOF at f/22 is 20-25 ft to infinity. A couple 55-58mm lenses say f/16, hyperfocus to 20 ft, DOF is 10 ft to infinity. A couple 135mm lenses say the same, but af f/22. Ansel Adams (THE CAMERA) agrees with the Photoguide, but at 80mm, not 115mm. These scattered answers aren't very helpful, eh?

But it definitely looks like, except on a view camera, or with a tilt-shift adapter [ see

Tilted plane focus - Wikipedia, the free encyclopedia ], it's hard get 10 ft to infinity DOF at focal lengths over 100mm on an APS-C camera, and hard to calculate the hyperfocal point. And you don't want to stop a lens all the way down to its smallest aperture anyway -- you start getting nasty diffraction effects. So:

* Mount a manual, marked 50mm lens (Takumar, Zeiss, whatever) on your cam;

* Set the INFINITY mark to just inside the mark for the next-to-smallest f-stop;

* The other f-stop mark should be around 6-8 feet; that's pretty good;

* Now you are in focus -- set the aperture; point the camera; shoot;

* In PP, crop the image so it looks like it was shot at 115mm.

Other options: Get an Olympus 4/3 system or any P&S with a sensor smaller than APS-C. The shorter lenses on smaller frames have greater DOF for the same FOV. (More noise, though.) Or get a view camera with a digital back and shoot at f/64. Or get a tilt-shift adapter -- but you may need to use medium-format lenses. Or stitch together a vertical panorama, with each tile being perfectly in focus, from 6 inches to infinity (I've done this). The easisest ways are probably: wider lens, and crop; and stitch-up. I'll stop now.