Originally posted by pschlute Bob
10x view is a 100% view. That means for each pixel that your LCD can display, it displays one pixel from the camera sensor. You may well be getting good focus using 16x, but each step above 100% will lead to pixelisation. It is a bit like viewing a 500 pixel wide picture in full screen mode on a 1920 wide monitor.
I understand now what you're referring to but that isn't exactly a 100% view - it is, as you said, a 1:1 pixel representation between the camera sensor and the LCD pixels (each of which is made up of even finer "dots" - RGB colored components). In my mind a 100%
view is a view which shows 100% of the original picture elements (1x - although 1x may not be exactly 100% of the sensor image).
When you get to that point (10x), you won't get any additional image resolution by jumping to 16x but it will enlarge the 10x image a bit more through interpolation, so it offers better focus reference.
Consider you're shooting a checkerboard target right at the K-1 limit (and the lens can deliver full resolution). This is would mean that adjacent sensor pixels would be alternating black & white values. When shown on the LCD at 1:1 (10x mag), one would be hard pressed to see the alternating pattern unless the LCD screen was viewed with a magnifier that resolved individual LCD pixels. Normal eyesight probably wouldn't do that, particularly if the LCD is viewed from some distance. It would tend to appear an even gray unless closely examined.
Electronic magnification
is capable of enlarging the checkerboard pattern even more (each checker will now cover more than one LCD pixel) so the sensor pattern could better be seen. This wouldn't necessarily result in any pixelation although it's open magnification as far as the camera sensor is concerned and no details beyond the camera sensor's capability would be observed. In fact, you could apply a 160x electronic magnification (10x 16x) which would show individual sensor pixels. Now you could see the checkerboard pattern on the LCD clearly but the edges of each checker are being interpolated so they don't represent that kind of sharpness at the camera sensor level. However, the best focus point could be judged by this enlarged pattern which would disappear when the lens is mis-focused.
16x magnification isn't that much more than 10x so the benefit is marginal but it's there to serve as a kind of extra
display boost since details at the LCD pixel level are hard to see with the naked eye (a bit like using a 1.6x magnifier on the ground glass of a view camera - it doesn't increase the lens resolution but it lets you see finer details for focusing).
Of course, all this assumes a tripod mounted camera with stable conditions because any camera motion is also magnified and the magnified modes offer less and less benefit with greater magnification if the camera is moving.
I've attached three images. The first is a checkerboard pattern. The second is an electronically enlarged section of that pattern. Note the edges are blurred but the pattern is intact. The third image is an electronically enlarged section of the original pattern when it is out of focus. Even though the pattern is electronically enlarged (interpolated), it still offers an improved judgment of the focus of the original (especially if one has bad eyesight).
If the first pattern was shrunk to the pixel level of the K-1 LCD, you probably wouldn't be able to see the checkerboard, but the other two images (shrunken to the same scale) would probably be visible even though they are enlarged totally by electronic means.