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Examples: Autofocus Accuracy (Nikon D810)
This page takes a look at how well the Sigma 135mm f/1.8 DG HSM Art focuses on the Nikon D810, out of the box, using conventional autofocus (not Live View contrast detect).
Nearly all the examples are wide open at f/1.8 so they also testify as to wide-open optical performance.
The weak point of most DSLRs is autofocus at distance. The autofocus system itself often lacks precision (scientific sense), and the lens can contribute by offering less than ideal optical performance and/or a lens motor not up to highly precise operation. NOT SO with the Sigma 135mm f/1.8 DG HSM Art, which is so well corrected optically that its wide open performance makes the job of the AF system as easy as it can be. The motor is also very fast and nearly silent.
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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 about 75 cents a day!
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.
