minniev wrote: ↑
Thu Jan 11, 2018 2:34 pm
These are all quite beautiful, each in its own way, yet they work as a set, too. I’d be hard put to choose a favorite since I like them all so much. Great compositions, subjects, exposure, color treatment. Whether you added that sheep is immaterial to me.
As for the tech stuff - I like the sharper version of the wide angle scene better in this instance, though I often prefer the softer ones in other instances. Individual taste is all. The equation for hand-holding seems fairly true for m43 too, but there are so many other factors - camera and lens weight, image stabilization, our own strength and steadiness. Another m43 quirk - diffraction happens earlier in the range. Before I switched to m43, I happily used f22 for many landscapes, but I found that with m43 that induced a lot of odd blur. Now tend to hang out around f5 - f-8 and have even shot landscapes at f1.8.
PLEASE Ignore me if you already know all this, but generally, f/22 is not necessary for landscapes. F/5 to 8 will work, not only fine but better in many if not most cases, considering all relevant factors. Even wide open will work, although most lenses are not at their best wide open; a stop or stop-and-a-half down is often where the "sweet spot" is. The "odd blur" you've noticed is due to a phenomenon called diffraction
, which is closely related to the re
fraction that we are all familiar with. Refraction
(he intoned pedantically while peering around the roomful of eager faces over the tops of his pince-nez in that curiously intense way he affected...) occurs when light passes through
a transparent or translucent medium (think atmosphere, glass, water), and the over-simple answer for why is that light slows down
very slightly when passing through, causing it to bend
slightly. You can see this with a glass of water and a straw. Put the straw in the water and it will appear to offset slightly before straightening out and continuing in its original direction. The water is not acting as a lens because it is not itself curved, but the light you perceive coming from the straw in the water is refracted as it slightly slows down, causing the perceived offset. It is why it so difficult to spear a fish while standing on the bank; refraction causes the fish to appear to be in a different place than it actually is.
is also caused by light slowing down, by (for lack of a better simile) "tripping" over a solid object in passing. It's much the same as a water wave arriving at a beach and breaking; the lower part of the wave strikes the bottom first and slows down, causing the upper part of the wave to break. If it were a light wave it would bend slightly toward the object. Light bends slightly around all solid objects. The solid-object edges of the blades of your iris diaphragm cause the light passing through to bend slightly toward
the edges and away
from the point of sharpest focus refracted by the lens. This causes a slight but measurable scatter, a defocusing, and the smaller the hole through which the light must pass the greater the scatter. f/22 causes more diffraction scatter than larger holes, and that's where your visible "odd blur" comes from. Pretty generally no lens is at is best either wide open or stopped all the way down. There is no real need for f/22 in most landscapes because there are many other factors affecting depth of field, one of the main ones being distance: the greater the range to the plane of sharpest focus (and there is only one) the greater the apparent
depth of field, and it is apparent; an illusion. Focal length is a factor (the reason the f/64 school stopped way down was they were using long focal lengths to cover large formats). True, if you are shooting to infinity with a large foreground object in frame and you want to hold sharp focus on it then you may be forced to use f/22 plus "hyperfocal" focus and accept some loss of overall sharpness for the illusion of greater depth of field. Piet Francke is an expert in focus stacking
, which overcomes the DOF challenge at very close focus. He doesn't need to stop down far, just to the lens's "sweet spot": he basically slices through a scene with multiple planes of sharpest focus, then assembles them into a stack. But now I'm off the rails on a tangent.
Suffice to say that very generally (very), very small apertures are not needed in landscape, and you heard that from The Sharp Freak Bunny himself! (f/8 and be there! Weegee)