Originally posted by mtansley I noticed that some of my P & S cameras can return very sharp images, on one of them I don't think you can even change the sharpening settings.
Small-frame P&S digicams produce very sharp images because they typically have very short and not-real-fast lenses. For instance my Olympus 770-SW has a 1/2.33" sensor (diagonal= 7.7mm) with a 6.7-20.1mm f/3.5-5.0 lens, FF-FOV-equivalent to ~38-114mm. At the short end (7/3.5), DOF is nearly infinite. At the long end (20/5), DOF is still pretty thick -- prefocusing to 10m gives DOF from 5m to infinity. With such focal lengths, damn near EVERYTHING in an image is sharp -- until the image is enlarged too much.
And that's the trick: Almost everything looks sharp if it's displayed small enough. Another example: My first still digicam (over a decade ago) was a Sony DAC-P20, with maximum 1216x912px (1.1mpx) output, and a fixed 6/4.5 lens, FF-FOV-equivalent to 42mm (normal). I sometimes shot it in its 3:2 mode for 1216x811px images. I also shot B&W film (I forget exactly which now) in an ancient Kodak Monitor 6x9cm folder. I made contact prints from the MF negs. I printed B&W images from the P&S at the same size, 6x9cm. Same-size prints, vastly different resolutions -- but mounted together, they're indistinguishable except under a magnifier.
As mentioned, those 'sharp' film snapshots were generally not printed large, nor on detail-revealing slick paper -- textured paper masks many flaws, eh? A 4x6in / 10x15cm print doesn't reveal a lot. A larger print can be mounted behind matte glass or plastic to soften details. Much sloppiness can be hidden. Those pixels aren't easily peeped.