Latest or all posts or last 15, 30, 90 or 180 days.
Upgrade the memory of your 2018 Mac mini up to 64GB
877-865-7002
Today’s Deal Zone Items... Handpicked deals...
$1398 $998
SAVE $400

$1798 $1198
SAVE $600

$151 $151
SAVE $click

$2299 $2069
SAVE $230

$240 $175
SAVE $65

$240 $175
SAVE $65

$1399 $1399
SAVE $click

$2198 $1998
SAVE $200

$2299 $1799
SAVE $500

$2000 $1500
SAVE $500

$898 $798
SAVE $100

$1799 $1799
SAVE $click

$1699 $1499
SAVE $200

$999 $799
SAVE $200

$1798 $1198
SAVE $600

$1997 $1797
SAVE $200

$3199 $3199
SAVE $click

$33 $33
SAVE $click

$199 $149
SAVE $50

$699 $549
SAVE $150

$400 $300
SAVE $100

$1699 $949
SAVE $750

$1199 $1099
SAVE $100

$1199 $1099
SAVE $100

$999 $949
SAVE $50

$1699 $949
SAVE $750

OWC Envoy Pro Elektron

Ultra-high performance across entire capacity, outperforms the competition.

Tiny, bus-powered, rugged, compact!


√ No more slow and noisy hard drives!

Zeiss Batis 25mm f/2 Distagon: MTF Series from f/2 - f/16 + Distortion

Get Zeiss Batis at B&H Photo.

Zeiss Batis 25mm f/2 Distagon

The Batis line is a new lens line for Sony mirrorless cameras (Sony A7 series). See the general discussion of the Zeiss Batis lenses.

I expect to have the Zeiss Batis 25/2 Distagon and Zeiss Batis 85/1.8 Sonnar in for extensive field testing sometime in June. Coverage will go into Guide to Mirrorless.

Subscribe to Guide to Mirrorless.

MTF

The MTF chart shows modest micro contrast at f/2. However, overall contrast is superb wide open, even into the corners, and that very high overall contrast is critical to visual impact of the image.

Most notable, the performance is exceptionally uniform at all apertures from center to corner. This is highly unusual for a 25mm lens.

Peak performance is at f/5.6, but f/4 will be nearly the same. Astigmatism can be seen, a property rarely absent in wide angle lenses.

Diffraction begins to assert itself at f/8, and by f/11 its effects are quite dulling. At f/16, the performance becomes much inferior to f/16. See Mitigating Micro Contrast Losses from Diffraction Blur in MSI. These behaviors are all expected and good in this sense: a lens that shows little effect from diffraction is not very good to begin with! In other words, the better the lens, the more diffraction throws a wet blanket onto performance.

MTF for Zeiss Batis 25mm f/2 Distagon from f/2 through f/16
Graphs courtesy of Carl Zeiss

Distortion

Distortion is typical for most wide angle designs in the 24/25mm range—about 1.5% with a mostly barrel distortion transitioning to pincushion at the edges and into the corners (“wave type distortion”).

Toggle to compare.

Distortion for Zeiss Batis 25mm f/2 Distagon
Graphs courtesy of Carl Zeiss

Vignetting

Vignetting to the extreme corner area is 2+ stops at f/2 without correction, and about 1.3 stops with correction. I’m generally not a fan of vignetting corrections, since vignetting is also a creative tool. It is potentially worrisome for gradient transitions, but if the camera does the correction in 14-bits internally (before the Sony 11+7 lossy compression file is saved), then it should nearly always be just fine.

Toggle to compare.

Vignetting for Zeiss Batis 25mm f/2 Distagon
Graphs courtesy of Carl Zeiss
OWC Accelsior 4M2 PCIe SSD
6000 MB/sec!
Mac or PC.


Ideal for Lightroom, Photoshop, video.
Capacity up to 16TB!

Best Deals, Updated Weekly
View all handpicked deals...

Sony Alpha a7R II Mirrorless Digital Camera (Body Only)
$1798 $1198
SAVE $600

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.