Latest or all posts or last 15, 30, 90 or 180 days.
Welcome to diglloyd.com
In-depth review coverage is by subscription.
Also by Lloyd: MacPerformanceGuide.com and WindInMyFace.com
First-time visitor

MTF for the Sigma 85mm f/1.4 DG HSM Art

Get Sigma 85mm f/1.4 DG HSM Art and Sigma DG HSM Art lenses at B&H Photo.

Sigma 85mm f/1.4 DG HSM Art

To recap my September 19 post

The Sigma 85mm f/1.4 DG HSM Art looks to be another fine 'Art' lens from Sigma, which is to say that it outperforms anything Nikon and Canon offer.

I’ll be testing the Sigma 85mm f/1.4 DG HSM Art and adding it to my Sigma Art lens reviews just as soon as it ships. At about $1199, the Sigma 85/1.4A offers performance that looks to be far superior to the Canon and Nikon competition, at a considerably lower price—see the MTF charts that follow.

  • Stellar optical performance
  • Updated AF system with 3X the Torque
  • Designed and tested for high mega-pixel cameras
  • Full frame coverage for Nikon F, Canon EF, Sigma SA mount
  • Aperture Range: f/1.4 to 16
  • Two Low Dispersion Elements
  • Super Multi-Layer Coating
  • Hyper Sonic AF Motor, Manual Override
  • Rounded 9-Blade Diaphragm
  • TSC Material, Brass Bayonet Mount
  • Compatible with Sigma USB Dock

With 14 elements in 12 groups including two elements claimed equivalent to fluorite, the Sigma 85/1.4A is a very highly corrected lens offering unbeatable distortion and outstanding performance. Its 86mm filter size further reinforces the idea that its performance can be expected to be outstanding: bigger tends to mean more measures were taken to to optimize the lens, just as the Zeiss Otus 85mm f/1.4 APO-Planar does.

Fit and finish are attractive, just like all its siblings, and more attractive than Nikon and Canon offerings, to my eye.

MTF

Sigma provides a low resolution MTF chart for f/1.4 only. It is silly to provide two charrs (computed and computed with diffraction at f/1.4), since diffraction is meaningless at f/1.4. Much more useful would be MTF (with diffraction) for the first several apertures.

MTF at f/1.4 looks to be outstanding, within the limits of what a 10 lp/mm and 30 lp/mm chart tells us (Zeiss uses 10/20/40 lp/mm). Overall contrast for coarse structures (red lines) tells us that the image ought to have a very nice “pop” overall. Contrast for fine structures at 30 lp/mm is very strong but 30 lp/mm is an inappropriate choice for high resolution digital—Sigma ought to be showing 40 lp/mm or 50 lp/mm, at least if the lenses are to be appropriately positioned relative to mostly mediocre Nikon and Canon glass (CaNikon show 10 and 30 lp/mm, which makes it weird to see Sigma take the low bar route).

Micro contrast is very high over the central 3/4 of the frame (15mm offset), dropping off gracefully as the frame edges and corners are approach (possibly just as good in these outer zones, but not in a flat plane, that is, a very mild field curvature).

MTF at f/1.4 for Sigma 85mm f/1.4 DG HSM Art
Rigorously lab tested and OWC certified.

diglloyd Inc. | FTC Disclosure | PRIVACY POLICY | Trademarks | Terms of Use
Contact | About Lloyd Chambers | Consulting | Photo Tours
RSS Feeds | Twitter
Copyright © 2008-2017 diglloyd Inc, all rights reserved.