I have been struggling to get my landscape shots in complete focus from fore to infinity.
I have tried focusing at hyperfocal distance. Which for my lens (90mm) is 12.08 feet at f 22.
However this has yielded less than adequate results.
When measuring the 12.08' distance. Does one measure from the film plane, from the front of the lens, or the rear of the lens?
How does one accurately measure for this technique for optimal results?
Can't be perfect. There is only one sharp area - where the lens is focused. The rest is a matter of degree out-of-focus. Movements can help a lot, but you haven't asked about that.Originally Posted by RodinalDuchamp
Usually closer to the center of the lens.When measuring the 12.08' distance. Does one measure from the film plane, from the front of the lens, or the rear of the lens?
For practical purposes the place to measure is from the aperture diaphragm, unless the source of your DOF table specifies otherwise. Strictly speaking the measure is from entrance pupil, but the difference in a nominal-normal or modest wide lens like yours is insignificant for DOF measurements.
People tend to believe these online calculators with their tenths or hundredths of a decimal place precision a little too much. There is such a thing as false precision.
Hyperfocal distance focusing will not give you perfectly sharp backgrounds as your foreground. It will only result in "close as possible" results, setting aside the other inherent limitations of lenses and haze/diffraction etc. What you're counting on when using hyperfocal focusing is that the blurriness of the background that results from this, is within the "normal" existing level of blurriness of the photo, so viewers can't detect it...as much.
Mathematics: For a lens focused at infinity, the smallest object that can be resolved effectively has the same size as the focal length divided by the aperture of the lens. Once you focus closer, that equation changes inevitably, and things become harder to resolve..
I follow this advice
The general rule for scenic photographs, where one wishes to maximize the depth of field, is as follows. Set the focus at the distance of the most distant object. Then set the lens opening to the size of the smallest object to be resolved in the foreground. No calculations needed!
http://www.trenholm.org/hmmerk/DOFR.html
Frankly, this effort to create pin-sharp backgrounds in landscape photography bugs me a little. We humans evolved to perceive depth, partly by the level of bluriness of things. It looks sort of HDR-ish when everything, from a rock nearby to a distant mountain peak, is pin-sharp.
This is a very interesting article. I'll have to sit and read thoroughly.
Note that hyperfocal distances depend on an allowable circle of confusion. With my Nikons and medium format, the lens markings can be used for hyperfocal determination. So, if I use F/8, and I place the far mark on infinity, then the other f/8 tick will correspond to the closest element in the scene that should be sharp...for a really small print. Leave the lens focused where it is, and stop down two more stops, i.e. to f/16. In effect, this would be accepting a much smaller blur as acceptable.
If you don't care about infinity, focus on the near, take a distance reading, focus on the far, take a reading. Set the lens in the middle of that spread. Read the f/stop that encompasses that distance spread, say f/8. Stop down two more stops. Take the picture.
With LF, I use the distance changed between the standard. There's an article about this on the LF homepage. It'll list ideal and acceptable spreads for various apertures. You can use a measuring tape or a ruler to measure the spread. I put an adhesive scale, one used for wood working equipment, on my camera.
“You often feel tired, not because you've done too much, but because you've done too little of what sparks a light in you.”
― Alexander Den Heijer, Nothing You Don't Already Know
With a 90 mm lens where you measure from makes very little difference.
You haven't told us all. Which DoF calculator did you use and what did you tell it?
I just checked my own DoF calculator. It says that a 90 mm lens @ f/22 focused to 12 feet will give acceptable sharpness from around 1.1 m to around 151 m, with a .1 mm CoC. This isn't the Dofmaster (http://www.dofmaster.com/dofjs.html) result of 6' to 3242' but Dofmaster and my calculator agree that with your setup DoF won't reach infinity. And the CoC of .1 mm that Dofmaster uses for 4x5 is much too large. It is good for contact printing at best. Smaller CoC, less DoF.
I used the scheider calculator on their website.
That's not a calculator, that's a table. And you misread it. See https://www.schneideroptics.com/info...x5/90depth.htm and try again.
Dan I used this which they call a calculator: https://www.schneideroptics.com/soft...Calculator.xls
However on the table you posted the hyperfocal length at f22 was listed at the bottom as 12.08. Maybe I am reading the table wrong, would you be able to help me find my error?
I also see that focusing to infinity has its merits at f32
But that brings me back to how does one determine focus, from film plane or diaphragm, or a different point.
Read upward. Your question has been answered.But that brings me back to how does one determine focus, from film plane or diaphragm, or a different point.
At some point you have to employ experience. Photography is not a lab experience.
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