Sharpness and Blur by Optics
Blur from optical behavior or subject-related issue..
When different areas of the frame are optimally focused sharply at different scene distances, sometimes markedly so.
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2023-03-22 Reader Comment: Fujifilm GF Lens Performance
2023-03-14 Lens Sharpness, and Why Optical Focus Shift is the #1 Suckiest Lens Compromise
2023-03-01 Sony FE 20-70mm f/4G: Should Arrive in a Few Days for Testing
2019-07-08 Reader Comment: Zeiss Loxia 21/2.4 and Voigtlander FE 21/1.4:
Blur from optical behavior or subject-related issue..
Digital capture technology is discrete, and not the same as film..
Focusing is more complicated than it first appears..
Controlling the zone of sharp detail..
Examples of Focus Stacking..
Getting peak performance from your lens.
Zone of focus, not plane of focus.
Actual example of field curvature..
Understanding resolution and contrast graphs..
Understanding astigmatism..
How to verify a good sample and assess all aspects of lens performance..
Illuminating examples of lens behavior..
All-arounder entry-level mid-range zoom for L-Mount..
Premium fast normal lens for L-Mount..
47 megapixel with Multi-Shot Hi-Res mode..
Fast apochromatic prime/wide lens for L-Mount cameras..
Fast apochromatic prime lens for L-Mount cameras..
Fast short telephoto lens for L-Mount cameras..
Sigma/Foveon true-color sensor in a DSLR body..
The best becomes better..
36 megapixels in a compact full-frame DSLR..
Nikon’s finest 70-200 zoom as of 2017..
In-depth review of the Canon EF 14mm f/2.8L II including flare, distortion, field curvature, resolution charts, numerous field examples and comparison to the Nikon 14-24mm f/2.8G. The Canon EF 14/2.8L II is a superb lens, but with some peculiarities which may enhance or degrade its appeal for different uses. The review is as much a “user guide” as a review; even if you use this lens it’s well worth your time to read this review..
Evaluates performance of the Nikon 70-200mm f/2.8 VR on the Nikon D3. Comparison with the Nikon 180mm f/2.8D ED-IF..
Ultra wide tilt/shift lens.
Escape the banale postcard look by shooting landscapes at f/1.4 or f/0.95..
Bread and butter zoom lens..
Full frame slightly wide normal lens, pancake form factor..
APS-C wide angle lens equivalent to 22mm on full-frame..
APS-C moderate wide angle lens equivalent to 33mm on full-frame..
APS-C normal lens equivalent to 53mm on full-frame..
APS-C slightly tele normal lens equivalent to 60mm on full-frame..
Canon’s compact high-performance 24mm prime..
Canon’s tiny and lovely pancake lens..
Is Canon’s f/1.2 lens really better than an inexpensive f/1.4 or f/1.8?.
Canon’s best-ever medium telephoto and with image stabilization..
Canon’s ultra-fast medium telephoto compared and in the field.
Canon 100mm f/2.8L Macro IS .
Canon’s updated fast 35mm prime, evaluated on Canon 5DS R..
Canon’s image stabilized 35mm..
Tamron’s ultra wide to medium fast zoom..
Fast constant-aperture ultrawide zoom..
Superwide optimized zoom lens..
Mid-range optimized groundbreaking f/2 zoom..
High performance mid-range zoom..
A whopping 4/3 stop faster than other lenses in its range..
The fastest extreme wide angle yet..
Sigma’s fast high performance wide angle..
Extraordinary optical efforts for outstanding performance..
Sigma’s fast and affordable moderate excellent wide angle..
Sigma’s fast high performance normal lens..
Sigma’s best portrait lens..
Fastest 135mm lens yet, with ultra high performance..
Wide angle tilt/shift lens at 28mm..
The Sigma 50mm f/1.4 is a worthy contender in the crowded 50mm area. See how it performs compared to the Canon EF 50/1.4 and EF 50/1.2L..
Explores options for 180mm lenses on the Nikon D3x, including the Leica 180/2.8 APO-Elmarit-R in Nikon mount, Nikon 180/2.8 ED, Nikon 70-200/2.8 VR, Nikon 70-300/4.5-5.6 VR, and Tamron 70-200/2.8. Updated: now includes the Voigtlander 180/4 APO!.
Nikon’s classic high speed normal lens.
Nikon’s latest 50mm lens compared with the Zeiss ZF 50/1.4, Nikon 50/1.4D and Sigma 50/1.4..
Nikon’s High Performance Moderately-Priced 50mm..
Nikon’s High performance normal lens.
State of the art design in a fast ultra wide angle lens..
Nikon’s fast ultra wide angle..
Versatile image-stabilized mid-range zoom..
Versatile autofocus wide angle..
State of the art design in a fast 24mm lens. Includes full-resolution images at f/1.4..
An ultra-fast older design still offers appeal on modern digital..
Comparing the new Nikon 60mm to its predecessors, and the Coastal Optics 60/4 APO..
A superlative multi-spectral lens with perfect color correction..
Extreme wide angle zoom..
Is the 3rd time the charm?.
Canon’s compact image stabilized wide angle zoom..
Canon’s premium mid-range zooms..
A fast moderate wide angle lens with some practical difficulties..
State of the art design in a fast 35mm lens..
Relatively inexpensive alternative to the pro 35/1.4G..
Nikon’s best-ever f/1.4 lens?.
Relatively compact super-telephoto zoom..
Comparing Nikon 16-35mm f/4 VR, 17-35mm f/2.8, 14-24mm f/2.8, 18-35mm, 24-70mm f/2.8 along with Nikon 20mm f/3.5, 24mm f/2, 28mm f/2, 35mm f/1.4 AIS, and more..
Comparing the 16-35mm f/2.8L II to most of Canon’s wide angle prime lenses. Optical performance, ergonomics, focus, build quality..
Comparing the Canon 17-40mm f/4L and 16-35mm f/2.L II..
Nikon’s ultra wide angle zoom and the Nikon 14mm f/2.8, critical focus shift behavior..
Medium format Zeiss glass in Hartblei precision tilt/shift lens barrels!.
Ultra wide angle lens for Canon and Nikon..
Options for a 24mm lens: Nikon 14-24/2.8G, Nikon 24-70/2.8G, Nikon 24/2 AI-S, Nikon PC-E 24/3.5. Sharpness, distortion, flare, field curvature, shooting impression and ergonomics..
Articles written for MediumFormat.com..
Wide angle 24mm equivalent for Phase One XF system.
Mid range zoom 27-54mm equivalent for Phase One XF system.
Compact normal 54mm equivalent for Phase One XF system.
Is 100 better than 45/50/60 megapixels?.
Adapting lenses delivers degraded results in most cases..
Compact wide angle.
Ultra wide angle equivalent to 19mm f/3.3. .
Compact wide angle.
Mid-range zoom lens equivalent to 26-53mm f/3.3..
Compact wide angle.
Moderate wide angle equivalent to 37mm f/2.3..
Slightly long zoom lens equivalent to 37-82mm f/3.3..
Slightly wide compact normal lens equivalent to 41mm f/2.9..
Standard normal lens equivalent to 52mm f/2.3..
Standard normal lens equivalent to 66mm f/1.4..
Ultra high speed telephoto equivalent to 90mm f/1.6..
Mirrorless large format with leaf shutter lenses, 3rd generation..
18mm equivalent..
25mm equivalent..
Normal lens equivqlent to 53mm..
Normal lens equivqlent to 32mm..
Normal lens equivqlent to 45mm..
Normal lens equivqlent to 53mm..
Medium format telephoto lens, 74mm equivalent..
Wide angle zoom for Pentax 645..
Medium telephoto macro lens for Pentax 645 digital and film..
Lens performance at 80 megapixels..
How does Leica’s medium format entry measure up in ergonomics, image quality, etc?.
Extreme wide angle with ultra high performance..
Moderate wide angle with low distortion..
Milvus garb for the venerable 15/2.8 Distagon, with improved lens coating..
The classic 21/2.8 Distagon improved..
Highest performing 25mm from Zeiss ever..
Classic design in the latest Milvus build..
Outstanding build and optical quality in a medium tele..
An Otus, in effect. Milvus garb for the 135/2 APO, with improved lens coatings on one element. See the ZF.2/ZE 135/2 review pages..
Sharpness and rendering..
Ultra high performance in an extreme wild wide angle lens..
A brilliant, but also colorful character..
Brilliant imaging, even wide open, but with a few quirks. (Review in progress) .
Ultra high performance with a fast aperture..
A gem with unusual close-focus..
An artist’s drawing tool..
Strokes of a master..
Balance and poise..
Comparing the two 50mm options near and far, more comparisons coming..
Versatility in a “normal” lens and macro too!.
Fast high performance APO wide angle..
Ultra high performance apochromatic normal lens, first in the Otus line..
Rendering style, bokeh and beauty..
Ultra high performance apochromatic medium telephoto, overview and technical..
Rendering style, bokeh and 'transparency' without peer..
Razor sharp with gorgeous bokeh..
King of bokeh! Corner-to-corner sharpness, world class..
Beautiful bokeh, razor sharp, superb color correction..
Articles written for Lenspire.ZEISS.com..
What to look for in a binocular, plus reviews..
Understanding lens performance..
Focus accuracy and focus shift..
Questions and answers on photography and computers and more..
Q&A on the 15/2.8 Distagon with Dr. Hubert Nasse.
A reference lens for color correction..
Medium format Zeiss glass in Hartblei precision tilt/shift lens barrels!.
Overview and assessments of Nikon lenses.
Leica S2 37.5 megapixel DSLR and its lenses..
Lenses for Leica M cameras, especially the M9.
Vintage 2006 comparative review of Nikon D200 vs Nikon D2x..
Compact ultra-wide zoom..
Fast ultra wide zoom lens..
Fast standard zoom lens..
Bread and butter all-around zoom..
All-arounder compact lens with macro capability..
High speed portrait lens optimized for Canon mirrorless..
Image quality..
Fast ultra wide angle for Nikon Z..
Fast wide angle for Nikon Z..
Ultra wide compact zoom for Nikon Z cameras..
Fast mid-range zoom expressly designed for Nikon Z cameras..
Mid-range zoom expressly designed for Nikon Z cameras..
Fast portrait telephoto for Nikon Z..
5th Generation standard-setting camera..
4th Generation standard-setting camera..
Ultra high performance extreme wide angle..
Compact ultra-wide angle lens..
High performance wide angle..
High performance, high speed..
Fast wide angle..
High performance mild wide-angle..
Fast and gorgeous moderate wide angle Zeiss design..
Compact moderate wide angle..
Fast high performance normal lens of Zeiss design..
Compact moderate wide angle for Sony mirrorless..
High performance, high speed..
High performance, high speed..
High performance, high speed..
Compact normal lens for full-frame Sony mirrorless..
Top-grade medium telephoto..
Top-grade telephoto..
Outstanding fast wide angle, DSLR optical design..
Native-mount ultra wide angle high performance zoom for mirrorless..
Native-mount mid-range zoom for mirrorless..
Ultra high speed native-mount moderate wide angle..
Ultra high performance medium telephoto..
Highly corrected medium telephoto..
Outstanding fast wide angle, DSLR optical design..
Macro lens also excellent for all-around shooting..
Anything wider would be a fisheye..
Fast high performance manual focus wide angle..
Fast mild wide angle lens..
Fast lens speed with curious rendering..
High-grade manual focus wide-normal lens..
High-grade manual focus normal lens..
Fast extreme wide angle zoom..
Extreme wide angle zoom..
Pro-grade f/2.8 wide angle zoom..
Comapact ultra-wide zoom for Sony full frame mirrorless..
Premiere mid-range zoom for Sony full frame mirrorless.
Premiere mid-range zoom for Sony full frame mirrorless.
Comapact mid-range zoom for Sony full frame mirrorless.
Wide angle to telephoto zoom with optical stabilization..
Extreme wide angle with 'zero distortion'..
Ultra wide angle lens adapted from DSLR, native E-mount, all manual..
Wide angle lens adapted from DSLR, native E-mount, all manual..
Does pricey M glass deliver on mirrorless?.
The best compact big-sensor digital camera yet?.
Fixed 28mm lens with APS-C sensor free of anti-aliasing blur with wonderful color..
Razor sharp 28mm lens on APS-C sensor and outstanding usability and features..
Full frame camera in an ultra-compact body with or without anti-aliasing filter..
Wide angle zoom equivalent (14-28mm equivalent)..
A high performance mid-range zoom..
A fast moderate wide angle..
Native Micro Four Thirds macro lens..
Compact wide angle equivalent to 16-36mm..
Fast, bright and well corrected wide angle..
A fast and lovely 'normal' lens (50mm equiv) for Micro 4/3..
Superb ergonomic design in a compact camera..
Can smaller sensor cameras compete with larger ones on any basis?.
Wide angle zoom equivalent to 15-36mm.
Moderate wide angle for Sony NEX..
Use DSLR lenses at ~native focal length, and gain a stop of speed..
Outstanding ultra wide angle performer..
Outstanding wide angle, superb performer..
Manual focus moderate wide angle for full-frame mirrorless..
Manual focus normal lens for full-frame mirrorless..
Autofocus extreme wide angle for Sony full-frame mirrorless..
Autofocus wide angle for Sony full-frame mirrorless..
All-around slightly wide angle/normal with close focus..
Ultra wide angle lens for Sony NEX or Fujifilm X..
Normal lens for Sony NEX or Fujifilm X..
Moderate telephoto macro lens for Sony NEX or Fujifilm X. Useful on full frame too!.
45mm f/2.8 equivalent FOV lens..
28mm f/2.8 equivalent lens on APS-C sensor..
Specific issues affecting usability..
Relative sharpness and performance across cameras..
Relative sharpness and performance vs APS-C cameras..
Field shooting the Leica MM, and comparisons..
Focal lengths, color, weight and travel considerations. [relevant, but dated/old material].
Leica’s ultra wide angle zoom lens..
Leica’s widest prime lens..
Leica’s fastest and widest lens..
Leica’s best-performing 21mm..
Leica’s fast wide angle..
A discontinued but excellent 24mm..
Leica’s best-performing 24mm, and with a flat field..
Leica’s fast 28mm..
Leica’s widest lens utilizing built-in frame lines..
Tweaked 2016 redesign..
Leica’s smallest and lightest M lens with superlative performance..
Leica’s superlative and most natural lens for the M..
High performance moderate wide angle..
Leica’s f/2 35mm for the M..
Six models to choose from..
World’s fastest 50mm full-frame lens..
Leica’s superlative normal lens..
Modern iteration of a classic design..
High performance but flawed 50mm normal lens..
Leica’s compact low-distortion normal lens..
Leica’s medium tele for Leica M..
Leica’s compact 90mm for the M..
Compact lens for portraiture or similar..
Superb all-around macro and general-purpose lens..
Notes and examples..
Fast and ultra high performance moderate wide angle rangefinder lens..
All around razor sharp performer..
Pleasing and relatively inexpensive normal lens.
Fast high performance wide angle..
A slightly slower, but smaller and lighter alternative to the Noctilux, at 1/10 the price..
ARCHIVAL MATERIAL. Terrific backup bodies or even primary body for M-mount lenses..
2023-03-22 Reader Comment: Fujifilm GF Lens Performance
2023-03-14 Lens Sharpness, and Why Optical Focus Shift is the #1 Suckiest Lens Compromise
2023-03-01 Sony FE 20-70mm f/4G: Should Arrive in a Few Days for Testing
2019-07-08 Reader Comment: Zeiss Loxia 21/2.4 and Voigtlander FE 21/1.4:
2019-05-04 Leica 50mm f/1.4 Summilux-SL ASPH: Impact of Field Curvature, Grassy Meadow (Panasonic S1R)
2018-10-19 Zeiss Batis 40mm f/2 CF Aperture Series: White Aspen, Late Dusk
2018-10-19 Zeiss Batis 40mm f/2 CF Aperture Series: Mountainside near Aspendell
2018-08-30 Nikon Z7: Optical Design vs the Large-Diameter Z-Mount and Short 16mm Flange Focal Distance
2017-10-12 Nikon D850: Mine Also Has a Problematic Flange Focal Distance (way past infinity mark).
2015-12-28 Sigma 20mm f/1.4 DG HSM Art Aperture Series: Pescadero Creek (Canon 5DS R)
2015-12-13 Sigma 20mm f/1.4 DG HSM Art Aperture Series: Field Curvature Assessment
2015-10-22 The Irrational Aim of f/1.4 Lenses
2015-04-07 Canon 24mm f/1.4L II: Field Curvature (Metreon)
2014-07-30 Sigma 50mm f/1.4 DG HSM A vs Nikon 50/1.4G and 50/1.8G (Nikon D810)
2014-07-24 A conversation with Ming Thein on the Pentax 645Z and Nikon D810 and More
2013-12-21 Supporting the Zeiss Otus 55mm f/1.4 APO-Distagon on the Sony A7R
2013-08-03 Leica 35mm f/1.4 Summilux-M ASPH: Field Curvature and Focus Shift on a Planar Subject
2013-08-01 Field Curvature of the Zeiss 15mm f/2.8 Distagon with Focus Bracketing
2013-07-25 MTF vs Field Curvature and Tips for Optimizing Focus
2013-07-13 Field Curvature with the Leica 50mm f/0.95 Noctilux-M ASPH
2013-06-29 Which 50mm Lens for Leica M?
2013-06-28 Leica 50mm f/2 APO-Summicron-M ASPH vs 50mm f/0.95 Noctilux-M ASPH
2013-06-08 Choosing a Leica M 50mm Lens
2013-05-28 Zeiss Touit 12mm f/2.8 Distagon: Field Curvature
2013-05-23 Zeiss Touit 32mm f/1.8 Planar: Reader Question on Field Curvature (and field curvature in general)
2013-04-26 Zeiss 15mm f/2.8 Distagon: Field Curvature, MTF, Focus (Mosaic)
2013-01-16 Reader Comment: Field Curvature
2013-01-15 Zeiss 15mm f/2.8 Distagon: Field Curvature, MTF, Focus (Mosaic)
2012-11-17 Olympus Zuiko 60mm f/2.8 ED Macro — Confirming Field Curvature In the Field
2012-11-14 Olympus Zuiko 60mm f/2.8 ED Macro — Field Curvature Assessment
2012-09-04 Canon 24mm f/2.8 IS: Field Curvature and Color Fringing Study
2012-07-18 Zeiss 25mm f/2 Distagon Field Curvature Study (Yosemite, Tioga)
2012-02-07 Nikon D800 / D800E — Lens Requirements for 36 Megapixels
2011-11-21 Supposing a 36 Megapixel Nikon DSLR Arrives... What About Lenses and Technique?
2011-03-20 Comparison and Analysis of Field Curvature for Zeiss 35mm f/1.4 Distagon
2010-07-08 Hasselblad user examines Leica S2 pre-review coverage
2009-01-31 Comparing lenses — field curvature
2009-01-17 Canon 5D Mark II and optics
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