The parish priest's temporary residence. K3 III + DFA 28-105 mm HD at 45 mm FL and f/11. Now, this is "Edge-to-Edge" sharpness.

[BigMackCam]

That does indeed look very sharp, Richard!

Just a minor point, but on a shot like this where large depth-of-field isn't a key consideration, you could technically squeeze even greater detail out of it by dropping to f/8 (since f/11 on the K-3III, with its high-res APS-C sensor, will be edging into diffraction territory). It almost certainly wouldn't be noticeable at this reproduction size, but you might see a difference in very fine detail at 1:1 reproduction...

[RICHARD L.]

Thank you for the tip. I'm still "doing my classes" with the K3 III and the learning curve is a little stiff. I tried a series of far-away pictures of the Saint Lawrence River @ f/8, f/11 and f/16 with this combo. I will probably post my findings next week.

Very well-corrected lenses can peak at f/8, best example is the P67 M* 300 mm f/4 on the 645Z : no need to close more than f/8 as there is no additional gain in sharpness. I noticed the same phenomenon with the P67 90-180 mm f/5.6 zoom on the 645Z : sharpness peaks @ f/8, it is "horrible" @ f/45.

Best Regards

[BigMackCam]

Thank you for the tip. I'm still "doing my classes" with the K3 III and the learning curve is a little stiff. I tried a series of far-away pictures of the Saint Lawrence River @ f/8, f/11 and f/16 with this combo. I will probably post my findings next week.

Very well-corrected lenses can peak at f/8, best example is the P67 M* 300 mm f/4 on the 645Z : no need to close more than f/8 as there is no additional gain in sharpness. I noticed the same phenomenon with the P67 90-180 mm f/5.6 zoom on the 645Z : sharpness peaks @ f/8, it is "horrible" @ f/45.

Wide-ranging zooms, in particular, always take some experimentation to find the optimum aperture for centre, edge and frame-wide resolution at each focal length, and on a particular camera. Mostly (though this is quite a generalisation) they're optically best around f/8 - f/11... but this is a tricky aperture range with high resolution sensors, because lens diffraction combined with the sensor's small pixel sizes means that shots are becoming diffraction-limited to some extent. The pixels on the K-3III's sensor are even smaller than those on the K-1, so the effects of diffraction will become noticeable at faster apertures. As such, a lens that delivers sharper results at f/11 than f/8 on the K-1 may deliver its best results at f/8 on the K-3III, beginning to look softer at f/11 and narrower. Experimentation is key... and you seem to do quite a bit of that, which is excellent. It's the best way to learn about any lens (or any piece of equipment, period)...

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Last edited by BigMackCam; 04-24-2022 at 12:22 PM.

[MikeNArk]

I have no disagreement with any of the previous comments. Based on this image and your earlier posted tests, F8 - F11 looks to be good aperture for this camera and lens combination. Good sharp image.

[RICHARD L.]

Indeed, f/8 seems to be the "top performer", closely followed by f/11.

Regards

[angkymac]

Very interesting info I get from this thread.
Helpful.
Thanks to all of you for your posts.
Angky.

[RICHARD L.]

I learned this long ago, you know : EXPERIMENT, EXPERIMENT, EXPERIMENT. Knowledge always triumphs.

Regards