Page 64 - NyghtVision Boot Camp One Fill Edition
P. 64
13. The Circle of Confusion
Changing the way the camera sees the world, 3.
Circle of Confusion overall distance from the subject.
Circle of confusion...... Not a topic often discussed by Minimum Focusing Distance
photographers or in photography books, but, none- Even with a macro lens, one can only get so close to
theless, one of the most important concepts to un- whatever one’s subject might be and still focus. That
derstand. Appropriately used, the Circle of Confusion distance is a function of the design of the lens itself.
can transform an adequate image into an emotionally This is the minimum focusing distance - the small-
powerful one. est focusing distance from an object to the front of
So, what is the Circle of Confusion? In simple terms, the lens. In many lenses, MFD is also a function of fo-
the Circle of Confusion is that area of an image that cal length - zooming in from “up close” can result in
is too sharp to be out of focus and too soft to be in fo- changing the MFD.
cus. The Circle of Confusion is present in every image Example: Canon’s 24-105 L Series lens, regardless of
- even if you can’t see it. Sometimes, it is so small that the focal range (24 and 105 for example) doesn’t ef-
it is easy to miss it. fectively change the MFD. However, on Canon’s 100-
So, how do you use the Circle of Confusion to create 400, focal distance completely alters the MFD if for no
emotionally powerful images? The Circle of Confusion other reason than the fact that the barrel of the lens
is a function of many things, perhaps the two most im- moves closer to or further from the object.
portant are Minimum Focusing Distance (MFD) and
64 Boot Camp, Part 1
