Originally posted by Kunzite The speed with which they're developed - not that fast, I'd say - isn't really relevant, as we're comparing them not only with mature technology, but also with the laws of physics: the speed with which the OVF is showing you images is the speed of light.
OVFs are faster to view, but slower to shoot. They have to move a mirror out of the way. It is likely to be easier to reduce the lag in EVFs than to reduce the mirror-movement delay. (Reaching 15 fps, say, may be tricky with mirrors, less so with EVF).
Originally posted by Fogel70 Do you really think you need a viewfinder with the speed of light?
EVF don't need speed of light, they only need to be fast enough so that human perception don't notice any difference from speed of light.
True! And, of course, we don't actually perceive things at the speed of light. A
lot of processing goes on between light falling on the retina and the perception of that image in the brain! Any impression that we see things instantly is an illusion.
Originally posted by IchabodCrane Here's the inherent drawback of an EVF (IMHO): The photographer is trying to capture a scene as it actually is and an OVF displays a scene "as it actually is".
Even when it is true that "the photographer is trying to capture a scene as it actually is", the photographer is handicapped because
that isn't what the camera itself is actually doing. It is transforming the image of the scene into something else: possibly similar, possibly better, possibly worse. An EVF offer the possibility of informing the photographer what the camera is capturing, so that the photographer can compensate.
If I want to know the scene
really looks like, I'll look at it directly, not through a viewfinder! The viewfinder is an aid to capturing the scene, and it can help to know what it is capturing. For example, is the camera clipping highlights or shadows?
Originally posted by derekkite The test of an evf is the ability to find a subject and track it using a 500mm lens.
That is an interesting test of
any viewfinder, and I certainly
can't do it reliably with an OVF! I am simply unable to get the results I want with my Sigma 500mm APO EX DG f/4.5. I'm not saying I could do it with an EVF instead - just that OVFs fail the same test,
at least for me. Perhaps that is also telling us what we already know - different photographers have different requirements, and succeed or fail in different ways with different technologies. (It would be interesting to know if there is any way that an EVF could help me track successfully with my 500mm lens).