Hyperfocal distance again

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parkmoy

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I started looking around for a hyperfocal distance table I could use to make a crib sheet for a couple of my lenses and found that there was quite a variation between some of the tables.

Investigating further I found that not only variations in circle of confusion, focal length and aperture came into it but also print size, viewing distance and how good the viewer's eyesight is all affected it and probably explained the table variations.

My question is, from a practical point of view, can any of you landscape gurus point me to a table that works as a happy medium? I don't want apps or online calculators, just a simple table that I can copy and use.
 
parkmoy said:
I started looking around for a hyperfocal distance table I could use to make a crib sheet for a couple of my lenses and found that there was quite a variation between some of the tables.

Investigating further I found that not only variations in circle of confusion, focal length and aperture came into it but also print size, viewing distance and how good the viewer's eyesight is all affected it and probably explained the table variations.

My question is, from a practical point of view, can any of you landscape gurus point me to a table that works as a happy medium? I don't want apps or online calculators, just a simple table that I can copy and use.
Click to expand...

The only happy medium I know is, Russel Grant.......

Seriously though, circle of confusion can be applied to lenses AND the printed photo - Google Circle of confusion for an explanation.
For lenses, CoC has a different value which is related to sensor size.
So your table needs to relate to the CoC for your particular sensor size e.g FF,APS-H, APS-C, 4/3, Compact, phone.
The smaller the sensor (or film media) the smaller in FL (and aperture) the resultant lens needs to be to get the same FOV.
Take a full frame lens say 50mm and compare that with a camera phone lens (very small sensor compared to FF), the phone lens is minute, as is the aperture and focal length, that gives the same FOV. These factors result in a significant change in CoC, which gives a much deeper DOF for the camera phone compared to the FF camera for the same (equivalent) FL.
 
Howi said:
The only happy medium I know is, Russel Grant.......

Seriously though, circle of confusion can be applied to lenses AND the printed photo - Google Circle of confusion for an explanation.
For lenses, CoC has a different value which is related to sensor size.
So your table needs to relate to the CoC for your particular sensor size e.g FF,APS-H, APS-C, 4/3, Compact, phone.
The smaller the sensor (or film media) the smaller in FL (and aperture) the resultant lens needs to be to get the same FOV.
Take a full frame lens say 50mm and compare that with a camera phone lens (very small sensor compared to FF), the phone lens is minute, as is the aperture and focal length, that gives the same FOV. These factors result in a significant change in CoC, which gives a much deeper DOF for the camera phone compared to the FF camera for the same (equivalent) FL.
Click to expand...

Thought Grant was an astrologer:)

All that you say may well be true BUT all I want is a reasonably reliable table so that I can work out what distance to focus at :shrug:
 
Here's a quick and easy guideline for achieving extensive DOF for landscapes. It won't maximise your near field sharpness, but it will come close and is very easy to remember....

Take your focal length and divide by 2. That will give you your aperture value.

Set focus to something more than 3m. 10m is fine, 100m, 1000m. You can go beyond that if you like but it won't make a difference. Just don't set focus too close.

Put it to the test in practice or run some numbers through DOFMaster and see if it works for you.

If near field sharpness is critical then it's down to the tables (or a phone app) to get precise values.

Enlargement size, viewing distance and visual acuity matter because the more you magnify the image and the more capable your eyesight the more easily you can observe unacceptable levels of softness. Most DOF charts assume a 10" print viewed from 12" away. The figures should apply equally to a 20" print viewed from 24" away, a 30" print viewed from 36" away and so on. But if you enlarge to 30" and still view from 12" away you will spot flaws that the standard tables do not account for.
 
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Thanks everyone for your help. I'm going with Rich's spreadsheet but I'll remember Tim's rule of thumb for when I forget the crib sheet;)
 
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