f/8 and be where?

I was reading Tim Barribeau’s [excellent article on µ4:3 lenses][m43 lenses], when I was taken aback:

> The oft repeated creed of the photojournalist is “f/8 and be there.” You can set this lens to infinite focal length, and anything more than 6 feet away will be in focus, making it great for candid shots.

This goes against my instinct. A 4:3 sensor with a wide-angle field of view, should do better than f/8.

Being anal, I had to check [DoFMaster][dofmaster]. Inputs: (E-P3, E-P2, E-P1), Focal length: 15mm 30mm equiv), f-stop: f/8, subject distance: 6.2feet

Hyperfocal distance: 6.2ft
Near limit: 3.1ft
Far Limit: Infinity

Translation: If you set this lens correctly (to six feet, not infinity), then everything from 3 feet to infinity will be in focus to within the ability of the sensor to resolve (any m4/3 sensor: at f/8 we’re at the diffraction limit of them all).

Now this bodycap doesn’t really have focus or a focus scale, so it is conceivable that the article statement is technically correct. But since this thing only has a focus lock in two positions — .3m and infinity — I have a hard time believing that the infinity focus is actually locked at infinity and not the hyper focal distance, giving it an extra 3 feet of focus room. If it is really set at infinity, then there should be a click stop somewhere at the hyperfocal distance.

I don’t have this lens so I can’t verify. But if the infinity lock doesn’t lock focus at 6 feet (focus down to 3 feet), I’d be surprised. (If it actually is an infinity lock, then I guess the recommendation is to lock at infinity and pull back a bit.)

grass

wheat… grass, really
China Camp State Park, Marin, California

Nikon D3, Nikkor 85mm f/1.4D. Canon 500D, handheld
1/250 sec @ f/8, iso200, 85mm

One of the dangers of “f/8 and be there” is that depth of field is very dependent on distance. When doing macro photography, even f/8 can not be enough. (Unless buttery bokeh is the effect you are intending, like in this photo.

[m43 lenses]: http://thewirecutter.com/reviews/the-first-micro-four-third-lenses-you-should-buy/ “The First Micro Four Third Lenses You Should Buy — The Wirecutter.”
[dofmaster]: http://dofmaster.com/dofjs.html “Online Depth of Field Calculator—DOFMaster”

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