I shoot Nikon 35mm film and 1.5x digital capture. The things I’m going to say apply universally, but you need to know some specifics of your camera.
The hyperfocal distance is directly connected to your circle of confusion value, which is directly related to the size of your imager. The larger the imager, the larger the circle of confusion value.
Here are the values and formulas for my cameras, where D = circle of confusion, and are easily memorized:
D = .025mm for 35 mm film
D = .020mm for 1.5x crop factor.
A Canon 1.3x camera would be somewhere about .023. A 6x7 medium format would be considerably larger. A 4x5 view camera would be way larger.
So here's the hyperfocal distance formula:
H = (L x L)/(F x D) This is your hyperfocal distance.
L = Focal Length of your lens. If you use a zoom, you need to note your setting.
F = Aperture, in F-stop values.
Your actual closest focus will be H/2, or half your hyperfocal distance. Notice that the D is in millimeters. If you want your hyperfocal distance in feet, you’ll need to convert at the last step. You’ll end up multiplying your result by 25.4 (millimeters in one inch) and then you multiply that by 12 (inches in one foot). But knowing this, you can make your life easier and just do it up front. In other words, you can convert your “D” values to this:
D = 7.62 (.025 * 25.4 *12) for 35mm film.
D = 6.1 (.020 * 25.4 *12) for 1.5x crop factor.
Thus my equation becomes:
H = (L x L)/(F x 7.62 or 6.1, depending on my format).
So lets say I’m shooting a city scape. I’ve got my 20mm lens on my FE2 35mm camera, and I’m thinking f5.6 is about right. Thus:
L = 20mm (lens focal length)
F = 5.6 (f stop setting)
D = 7.62 (circle of confusion with feet and inch constants thrown in)
H = (400)/(5.6 x 7.62) = 9.37 feet. This is my hyperfocal distance. The actual focus will be roughly 5 feet in front of me to infinity.
After studying the formula, you can see the hyperfocal distance has everything to do with the circle of confusion value, which has everything to do with the imager size. This explains why Ansel Adams and his buddies named their group “F64.” This kind of f stop is unheard of in smaller formats like 35mm and modern DSLRS, but necessary to achieve hyperfocal distances on large view cameras.