Imagery: Auto - Large Table of Contents

EXCERPT page containing first few paragraphs. 2021-12-04 14:17:56
UA_SEARCH_BOT_null @ 54.227.97.219

Canon 100mm f/2.8L: Blur example 2

This page evaluates a second brand-new sample of the 100/2.8L IS. Like the first sample, it has an optical alignment problem, though the problem is considerably muted compared to the first awful sample.

In field shooting, I observed some unexplained sharpness across the frame, which I first dismissed (mentally) as field curvature of variations in focus. Still, an uneasy sense remained that something was amiss.

The subject

I set up a careful tripod comparison on my best outdoor test target: a detailed mosaic at Stanford’s Memorial Church. For the 100/2.8L, image stabilization was disabled, and my usual careful protocol involving mirror lockup was used. I shot the lenses three times each, refocusing each time.

The camera was angled just slightly up, an intentional device to help reveal the plane of actual focus. Foreground and backup (top) help also in analysis. Focus was on the two pink flowers near center. Lighting was dull overcast and no attempt was made here to spiff up the results.

Article continues for subscribers...

Diglloyd Advanced DSLR is by yearly subscription. Subscribe now for about 16 cents a day ($60/year).
BEST DEAL: get full access to ALL 8 PUBLICATIONS for only 68 cents a day ($249.95)!

Diglloyd DAP is DSLR-oriented, but also contains workflow and other topics. Much of the focus is on Canon and Nikon but also Pentax and Pentax medium format.

Special emphasis is placed on lens evaluation, focusing on Canon and Nikon and Sigma lenses, but with a few others like Rokinon/Samyang.

  • Make better images by learning how to get the best results right away.
  • Save money by choosing the right lens for your needs the first time, particularly some of the new Sigma Art lenses vs Nikon and Canon.
  • Workflow discusses image organization, raw conversion and post processing. Many examples show processing parameters for direct insight into how the image was converted.
  • Jaw-dropping image quality found nowhere else utilizing Retina-grade images up to full camera resolution, plus large crops [past 2 years or so].
  • Real world examples with insights found nowhere else. Make sharper images just by understanding lens behavior you won’t read about elsewhere.
  • Aperture series from wide open through stopped down, showing the full range of lens performance and bokeh.
  • Optical quality analysis of field curvature, focus shift, sharpness, flare, distortion, and performance in the field.

Want a preview? Click on any page below to see an excerpt as well as extensive blog coverage, for example on Nikon or on Canon or on Pentax.

Entire frame as shot

diglloyd Inc. | FTC Disclosure | PRIVACY POLICY | Trademarks | Terms of Use
Contact | About Lloyd Chambers | Consulting | Photo Tours
RSS Feeds | Twitter
Copyright © 2021 diglloyd Inc, all rights reserved.