Imagery: Auto - Large Table of Contents

EXCERPT page containing first few paragraphs. 2023-05-30 11:26:00

Blur by Manual Focus Inconsistency

No one can focus exactly same every time, not even autofocus is always consistent.

Example — Leica M9 rangefinder

The ten actual-pixels crops shown below were from 10 frames shot on the Leica M9 with the 50mm f/0.95 Noctilux-M ASPH. I used a tripod to eliminate any variable except my own eye.

How accurately could I focus the Noctilux? Rather badly! At least on this subject at this distance. Granted, this is f/0.95, and the fine-ness of detail is a challenge for a rangefinder at the distance I shot (perhaps 70 feet). But real life doesn’t provide large high-contrast black and white targets for one’s ease of focusing.

Following this test, I promptly purchased the 1.25X magnifying eyepiece. It definitely helps, but subsequent experience suggests that the 1.4X would be even more advisable to reduce the error further (that’s assuming perfect lens/camera alignment).

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Save yourself those years of trial and error by jump-starting your photographic technical execution when making the image. The best lens or camera is handicapped if the photographer fails to master perfect shot discipline. High-resolution digital cameras are unforgiving of errors, at least if one wants the best possible results.

  • Eases into photographic challenges with an introductory section.
  • Covers aspects of digital sensor technology that relate to getting the best image quality.
  • Technique section discusses every aspect of making a sharp image handheld or on a tripod.
  • Depth of field and how to bypass depth of field limitations via focus stacking.
  • Optical aberrations: what they are, what they look like, and what to do about them.
  • MTF, field curvature, focus shift: insight into the limitations of lab tests and why imaging performance is far more complex than it appears.
  • Optical aberrations: what they are, what they look like, and what to do about them.
  • How to test a lens for a “bad sample”.

Intrigued? See Focusing Zeiss DSLR Lenses For Peak Performance, PART ONE: The Challenges, or (one topic of many) field curvature.

Focus accuracy with Leica M9 + 50mm f/0.95 Noctilux-M ASPH

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