Imagery: Auto - Large Table of Contents

EXCERPT page containing first few paragraphs. 2021-12-02 17:27:41

Sigma FE 85mm f/1.4 DG DN Art


This page looks at the hideous pincushion distortion of the Sigma FE 85mm f/1.4 DG DN Art. The distortion is so strong that it really makes distortion correction all but mandatory.

Pincushion distortion is far more unnatural looking than barrel distortion, particularly for human faces, but it is also a Big Deal for horizons, architecture, etc. The world tends to bow-out or round-out, not pinch in as with pincushion distortion—it feels unnatural to me.

The de-facto requirement to correct this level of distortion guarantees sub-optimal micro contrast and sharpness in a substantial portion of the central areas of the frame. That makes the sharpness and MTF chart misleading at best.

Article continues for subscribers...

Diglloyd Guide to Mirrorless is by yearly subscription. Subscribe now for about 25 cents a day ($90/year).
BEST DEAL: get full access to ALL 8 PUBLICATIONS for only 68 cents a day ($249.95)!

Diglloyd Guide to Mirrorless offers comprehensive integrated coverage of most APS-C and full frame mirrorless cameras and lenses.

Special emphasis is placed on Sony full-frame, including Sony lenses and the high performance Zeiss Batis and Zeiss Loxia lenses plus Rokinon/Samyang and others. Fujifilm X, Olympus and Panasonic M4/3, Sigma dp Merrill and dp/sd Quattro are also covered in depth. Years in the making, it offers a wealth of material for choosing and using a mirrorless camera.

  • Make better images by learning how to get the best results right away. For example, the best way to set up your Sony camera.
  • Save money by choosing the right lens for your needs the first time, particularly with the numerous lenses available for Sony.
  • Make better images, a sort of “cheat sheet” saving yourself months or years of ad-hoc learning—best practices and how-to and processing parameters are discussed and shown.
  • Jaw-dropping image quality found nowhere else utilizing Retina-grade images up to full camera resolution, plus large crops.
  • 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 Sony.

Built-in lens profile does not correct hideous pincushion distortion — approximate manual correction shown
Variants Uncorrected,Corrected available in full article
f1.4 @ 1/100 sec handheld, ISO 800; 2020-09-11 08:15:38
Sony A7R IV + Sigma FE 85mm f/1.4 DG DN Art
RAW: +40 Whites, +15 Clarity, USM {15,50,0}

[low-res image for bot]

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.