New answers tagged

0

The image is sharpest at the focus distance. Many lenses have markings that roughly indicate that distance but you can also extract it from EXIF data shot from a digital camera. Sharpness decreases away from the plane of focus. Depth-of-Field is simply a concept to describe a range of distances which are sufficiently sharp. Sufficiently sharp depends on the ...


2

Never forget: depth of field is a myth. The term is a convenient shorthand for a standard of how much defocus is acceptable, and is dependent on the ultimate size of the print or level of magnification in examination, as much as the magnification on the negative or sensor. At the highest resolution examination, even with a very small aperture, the plane of ...


2

The clearest image of an object is always when the object is in focus — at the plane of focus. That is, for a given lens of focal length ƒ, when the lens is positioned a distance v from the camera sensor, then an object at distance u from the lens is in focus in accordance with the thin lens approximation, ƒ-1 = u-1 + v-1.


1

Your question seems to be based upon an assumption that a human viewer can see the difference between "blurry" and "in focus" at the system limits of a lens system. This is usually far from the case without magnifying the results by a large factor. Can we use the imaging of the convex lens on the screen to explain hyperfocal distance? Not very well. Why? ...


2

"Hyperfocal" refers to the condition where depth of field allows the lens to be "in focus" from some minimum distance to infinity. This depends on a core assumption: the size of the acceptable "circle of confusion," which is determined by the actual aperture diameter and lens focal length, but also by the amount of enlargement the image will receive before ...


2

Distant background blur for a 50mm/F1.8 setting exhibits a blur diameter of 50mm/1.8 as measured in the focus plane. What is "distant"? Well, at double the focus plane distance, you already have half of that diameter. So assuming your wave was in focus, how large would a disk of 27mm diameter swimming in your wave appear in the image? That's the diameter ...


-1

I don't buy lenses without distance scale on them. I don't buy cameras without dept of field preview. I am an amateur who takes his time when taking pictures and want to have all my options available.


Top 50 recent answers are included