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focus skew

Asymmetric zone of focus due to either lens skew or lens mount / sensor parallelism

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2021-09-23 Leica 50mm f/2 APO-Summicron-SL ASPH Aperture Series: Unacceptable Optical Swing (Lens Skew) + Reader Comments

2021-07-08 Sony FE 50mm f/1.2 GM Aperture Series: Example of Unacceptable Lens Skew

2020-10-23 Compared @ 14mm: Swing and Tilt, Optical Decentering — two Sony FE 12-24mm f/2.8 GM and Sigma FE 14-24mm f/2.8 DG DN Art

2020-10-18 Swing and Tilt: Subject Distance vs Lens Focusing Offset

2020-10-18 Analyzing Swing and Tilt of Sony A7R IV with Two Samples of Sony FE 12-24mm f/2.8 GM

2020-10-16 Update on Sony A7R IV Lens Mount / Sensor Parallelism, Lens Skew of Sony FE 12-24mm f/2.8 GM, Coming Field Shooting

2020-10-12 Lens Mount / Sensor Parallelism Inaccuracies Afflict All Brands

2020-10-08 Is It Even POSSIBLE to get a properly aligned Sony A7R IV?

2020-10-07 Sony A7R IV in for Repair of Lens Mount / Sensor Parallelism Problem

2020-10-01 Sony FE 12-24mm f/2.8 GM Aperture Series: Big Tree at Bend in Alpine Creek (jaw-dropping focus shift and lens skew)

Camera and Lens Tolerances

Sharpness issues related to camera and lens tolerances and build quality..

1. Mount Flange to Sensor Parallelism
2. Case Study: Severe Lens Skew (D800E, Samyang 14mm f/2.8)

Optical Behavior (Case Studies)

Illuminating examples of lens behavior..

1. Lens Skew (Nikon D800E, Sigma 35/1.4)
2. Lens Asymmetry/Blur With Fuji X100
3. Lens Asymmetry/Blur With Sony NEX-7 + 24mm ƒ/1.8 Sonnar

Panasonic Lumix S PRO 50mm f/1.4

Premium fast normal lens for L-Mount..

1. Aperture Series: Pines by Creek (Panasonic S1R)
2. Shootout: Leica 50mm f/1.4 SL vs Panasonic LUMIX S PRO 50mm f/1.4: Rotten Log

Leica 50mm f/1.4 Summilux-SL ASPH

Fast apochromatic prime lens for L-Mount cameras..

1. Shootout: Leica 50mm f/1.4 SL vs Panasonic LUMIX S PRO 50mm f/1.4: Rotten Log

Leica 50mm f/2 APO-Summicron-SL ASPH

Fast short normal lens for L-Mount cameras..

1. Lens Skew, Optical Swing
2. Aperture Series: View North to Mt Conness from Puppy Dome

Pentax HD FA 15-30mm f/2.8 ED SDM WR

Full frame ultra wide angle zoom..

1. Aperture Series @ 30mm, with Pixel Shift: Mosaic (Pentax K-1 SuperRes)

Sigma 24-35mm f/2 DG HSM Art

Mid-range optimized groundbreaking f/2 zoom..

1. Shootout: vs Sigma 24-105mm f/4A: Colorful Creek

Sigma 24mm f/1.4 DG HSM Art

Sigma’s fast high performance wide angle..

1. Aperture Series: Checking for Lens Symmetry, Bristlecone on Bare Hill (Canon 5DS R)

Sigma 35mm f/1.4 DG HSM Art

Sigma’s fast and affordable moderate excellent wide angle..

1. Lens Skew (Nikon D800E)
2. Lens Skew Confirmation (Nikon D800E)

Samyang 14mm f/2.8

Ultra wide angle lens for Canon and Nikon..

1. Lens Skew / Asymmetry Focus Bracket
2. Aperture Series: Wyman Cabin

Schneider Kreuznach LS 80mm f/2.8

Compact normal 54mm equivalent for Phase One XF system.

1. Aperture Series: Mosaic (IQ4 150)

Schneider Kreuznach LS 240mm f/4.5 IF

Long telephoto 162mm equivalent for Phase One XF system.

1. Aperture Series: Mosaic (IQ4 150)

Fujifilm GF 23mm f/4 R WR

Ultra wide angle equivalent to 19mm f/3.3. .

1. Focus Stacking Examples, Eastern Sierra (GFX100)

Fujifilm GF 32-64mm f/4 R LM WR

Mid-range zoom lens equivalent to 26-53mm f/3.3..

1. Examples: Eastern Sierra (GFX 50S)

Fujifilm GF 35-70mm f/4.5-5.6

Compact wide angle.

1. Aperture Series @ 70mm: Fresh Snow on White Mountain Forested Hills

Fujifilm GF 45-100mm f/4 R LM OIS WR

Slightly long zoom lens equivalent to 37-82mm f/3.3..

1. Aperture Series @ 56mm: Alabama Hills Desert Wash, Sunrise View To Mt Whitney

Fujifilm GF 63mm f/2.8 R WR

Standard normal lens equivalent to 52mm f/2.3..

1. Compared: 63mm f/2.8 vs 32-64mm f/4 (GFX 50S, Pine Creek South Fork)

Hasselblad XCD 35-75mm f3.5-4.5

Normal lens equivqlent to 53mm..

1. Aperture Series @ 75mm: View over Alabama Hills Granite Formations to Last Orange Light on Mt Whitney

Hasselblad XCD 65mm f/2.8

Normal lens equivqlent to 53mm..

1. Aperture Series: View Over Alabama Hills Formations to Mt Whitney Range, Dusk
2. Aperture Series: View Over Alabama Hills Formations, Last Light on High Peaks

Hasselblad XCD 80mm f/1.9

Moderate telephoto..

1. Aperture Series: Alabama Hills Formations, Late Dusk

Hasselblad H4D 50 Megapixel Medium Format DSLR

How does Hasselblad’s 3rd generation medium format entry measure up?.

1. Examples with HCD 28mm f/4 (Yosemite)

Canon RF 15-35mm f/2.8L IS USM

Fast ultra wide zoom lens..

1. Examples: Eastern Sierra

Nikon NIKKOR Z 14-30mm f/4 S

Ultra wide compact zoom for Nikon Z cameras..

1. Aperture Series @ 30mm: Bleached Trees in Old Beaver Pond

Sony FE 14mm f/1.8 GM

Ultra high performance extreme wide angle..

1. Aperture Series: Greenstone Lake

Sony FE 20mm f/1.8 G

Compact ultra-wide angle lens..

1. Examples: Inyo National Forest
2. Aperture Series: Alabama Hills Granite Monolith, Sunrise
3. Aperture Series: View Towards Big Pine and Eastern Sierra, Dusk

Sony FE 35mm f/1.4 GM

High performance mild wide-angle..

1. Shootout vs Voigtlander FE 35/2 APO-Lanthar: Pine Creek Cliffs

Sony FE 50mm f/1.2 GM

High performance, high speed..

1. Lens Skew
2. Aperture Series: Rainstorm Over White Mountains

Sigma FE 14-24mm f/2.8 DG DN Art

Native-mount ultra wide angle high performance zoom for mirrorless..

1. Aperture Series @ 24mm: Teak Bench Closeup
2. 3-Way Shootout @ 18mm: Mosaic (Sony A7R IV)
3. Compared @ 14mm: Swing and Tilt, Optical Decentering — Sigma FE 14-24mm f/2.8 DG DN Art and Two Sony FE 12-24mm f/2.8 GM

Sigma FE 24-70mm f/2.8 DG DN Art

Native-mount mid-range zoom for mirrorless..

1. Aperture Series @70mm: View Past Lone Pine Campground to White Mountains

Sigma FE 45mm f/2.8 DG DN Contemporary

Compact native-mount normal lens..

1. Aperture Series: Mosaic (Sony A7R IV)

Voigtlander FE 35mm f/2 APO-Lanthar Aspherical

High-grade manual focus wide-normal lens..

1. Shootout vs Sony FE 35/1.4 GM, Sigma FE 35/2 DG DN: Pine Creek Cliffs

Sony FE 12-24mm f/2.8 GM

Fast extreme wide angle zoom..

1. Compared @ 14mm: Swing and Tilt, Optical Decentering —two Sony FE 12-24mm f/2.8 GM and Sigma FE 14-24mm f/2.8 DG DN Art
2. Aperture Series @ 17mm: Big Tree at Bend in Alpine Creek

Sony FE 12-24mm f/4 G

Extreme wide angle zoom..

1. Imaging Performance @ 12mm, Single Frame vs Stacked: Pine at Morgan Lake
2. Imaging Performance @ 24mm, Single Frame vs Stacked: Downed Tree, Last Kiss of Sunlight
3. 3-Way Shootout @ 18mm: Mosaic (Sony A7R IV)

Sony FE 16-35mm f/2.8 GM

Pro-grade f/2.8 wide angle zoom..

1. 3-Way Shootout @ 18mm: Mosaic (Sony A7R IV)
2. 3-Way Shootout @ 24mm: Rock Creek Meadow

Panasonic Lumix G LEICA DG MACRO-ELMARIT 45mm f/2.8 ASPH MEGA O.I.S

A macro lens with high performance..

1. Examples: Build Quality — Lens Skew Blur on Left
2. Examples: Bristlecones and Yosemite

Leica 50mm f/2 APO-Summicron-M ASPH

High performance but flawed 50mm normal lens..

1. Aperture Series: Church Mosaic and Lens Skew (M240)

Blog posts, reverse chronological

2021

2021-09-23 Leica 50mm f/2 APO-Summicron-SL ASPH Aperture Series: Unacceptable Optical Swing (Lens Skew) + Reader Comments

2021-07-08 Sony FE 50mm f/1.2 GM Aperture Series: Example of Unacceptable Lens Skew

2020

2020-10-23 Compared @ 14mm: Swing and Tilt, Optical Decentering — two Sony FE 12-24mm f/2.8 GM and Sigma FE 14-24mm f/2.8 DG DN Art

2020-10-18 Swing and Tilt: Subject Distance vs Lens Focusing Offset

2020-10-18 Analyzing Swing and Tilt of Sony A7R IV with Two Samples of Sony FE 12-24mm f/2.8 GM

2020-10-16 Update on Sony A7R IV Lens Mount / Sensor Parallelism, Lens Skew of Sony FE 12-24mm f/2.8 GM, Coming Field Shooting

2020-10-12 Lens Mount / Sensor Parallelism Inaccuracies Afflict All Brands

2020-10-08 Is It Even POSSIBLE to get a properly aligned Sony A7R IV?

2020-10-07 Sony A7R IV in for Repair of Lens Mount / Sensor Parallelism Problem

2020-10-01 Sony FE 12-24mm f/2.8 GM Aperture Series: Big Tree at Bend in Alpine Creek (jaw-dropping focus shift and lens skew)

2019

2019-09-05 Fujifilm GF Lens Quality Control = Unacceptable

2017

2017-08-19 Sony 12-24mm f/4 G @ 12mm: Single Frame Performance at f/11 vs Focus Stacking at f/11 (Pine at Morgan Lake)

2015

2015-07-20 Sigma 24mm f/1.4 DG HSM Art Aperture Series: Bristlecone on Bare Hill, Checking for Lens Symmetry (Canon 5DS R)

2015-07-16 Left/Right Zone of Focus Skew: Not Always the Lens, the Sensor and Lens Mount Might not be Plane-Parallel

2015-04-04 Tamron SP 15-30mm f/2.8 Di VC USD: Focusing Problems and Lens Skew

2013

2013-09-06 Samyang 14mm f/2.8: Lens Skew Asymmetry

2013-08-12 Lens Skew with the Leica 50mm f/2 APO ASPH?

2013-02-22 Lens Skew Study added to MSI

2013-02-20 Sigma 35mm f/1.4 DG HSM: Lens Skew Confirmation (Alternate Scene)

2013-02-20 Sigma 35mm f/1.4 DG HSM: Lens Skew