BetterPhoto Q&A
Category: Photographic Field Techniques

Hyperfocal Points and Lens Focus Scales

I have one last question regarding hyperfocal distance. :)

If I am using a focal length such as 60mm, the hyperfocal point is over 20', and the lens focus scale stops at 15' then goes to infinity, what should I do? Should I just focus on infinity, changing the focal length is not an option?

I have found the hyperfocal distance very helpful, but I've also found that you (at least I) can't use it when your focus scale doesn't give you that distance as an option. I am finding that this occurs mostly at the higher focal distances of my zoom lenses. For example, I most often use a 28mm-80mm, and 80mm - 200mm for landscapes. On my 28/80, anything after 55mm, I can't focus on the hyperfocal point; and with my 80/200, anything after 150mm, I can't use the hyperfocal point. The focus scales simply don't step up that far.

Any and all help would be greatly appreciated.

Cheers,
Glenn

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August 08, 2001

If you have a DOF markings for lens apertures on the lens barrel, look at where exactly where focusing index lines up with the infinity marking. Then move that location to the DOF index for the lens aperture. DOF markings are approximate, so this is a starting point. If in doubt and I'm willing to give up a little at the near end to ensure infinity remains in apparent focus, I'll set focus for the next tighter aperture than the one being used (e.g. set the inifinity mark to the f/11 DOF mark when using f/8 on the lens).

Sadly, many current AF lenses do not have DOF markings. If your lenses do not, the best you can do is interpolate between the focus scale markings. With nearly all lenses they're approximate to begin with. A simple experiment with objects in the foreground at the near limit and very distant background using a few frames of film can be used to verify exactly where to set it.

As an aside, this seems to be more of a problem with zoom lenses than with primes, or at least the ones I have. A few of my older manual focus primes appear to have been marked rather conveniently regarding hyperfocal distances.

-- John

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August 11, 2001

I see you're still struggling with your DOF! Just a note to let you know you're not alone, love!

Let me know when you've got it--you can explain it to me.....

pc

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August 11, 2001