Soft focus
{{Short description|Lens flaw}}
{{About|the term used in photography and optics|other uses|Soft Focus (disambiguation)}}
{{Use dmy dates|date=October 2022|cs1-dates=y}}
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| image1 = Bottle Softfocus 2.jpg
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| alt1 = A glass bottle with a green bottlecap; the lens has applied a heavy soft focus effect, resulting in halation around highlights and a hazy, dreamy texture.
| caption1 = An image of a bottle with a heavy soft focus effect.
| image2 = Bottle Softfocus 0.jpg
| width2 = 170
| alt2 = The same glass bottle with a green bottlecap; in this case, the lens has applied no soft focus effect, resulting in a normal, sharp texture.
| caption2 = An image of the same bottle, but without soft focus.
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In photography, soft focus is a lens flaw, in which the lens forms images that are blurred due to uncorrected spherical aberration. A soft focus lens deliberately introduces spherical aberration which blurs fine texture in the image while retaining sharp edges across areas of high contrast; it is not the same as an out-of-focus image, and the effect cannot be achieved simply by defocusing a sharp lens. Soft focus is also the name of the style of photograph produced by such a lens.
Photography
=Effect=
Soft focus has been described as "an image that is in focus but has a halo of out-of-focus images around it."{{cite book |url=https://archive.org/details/visualdictionary0000prak/page/232/mode/2up |title=The visual dictionary of photography |page=232 |publisher=AVA Publishing |date=2010 |isbn=978-2-940411-04-7}} The first deliberate use of undercorrected spherical aberration, resulting in halos around highlights (also known as "pearly" highlights),{{cite web |url=https://www.cameraeccentric.com/static/img/pdfs/kodak_1.pdf |title=Kodak Portrait Lens 305mm (12-in.) f/4.8 |date=1952 |publisher=Eastman Kodak Company |access-date=29 July 2024}} is thought to have been by French pictorialists around 1900, spreading to the United States, where these lenses were most popular between 1910 and 1930.{{cite book |url=https://archive.org/details/photographiclens0000nebl |title=Photographic lenses |first1=C. B. |last1=Neblette |first2=Allen E. |last2=Murray |date=1973 |publisher=Morgan & Morgan, Inc. |location=Dobbs Ferry, New York |isbn=0-87100-070-9 |lccn=64-20637 |edition=Revised |access-date=29 July 2024 |url-access=registration}}{{rp|106}} Noted practitioners of soft focus photography include Julia Margaret Cameron,{{cite news |url=https://www.theguardian.com/artanddesign/2015/sep/22/julia-margaret-cameron-victorian-portrait-photographer-exhibitions |title=Julia Margaret Cameron: soft-focus photographer with an iron will |first=Charlotte |last=Higgins |date=22 September 2015 |work=The Guardian |access-date=30 July 2024}} Bob Guccione,{{cite web |url=https://photofocus.com/photography/shooting-photography/tech-corner-soft-effect-lenses-and-filters-still-relevant-after-all-these-years/ |title=Tech Corner: Soft Effect Lenses and Filters-Still Relevant After All These Years... |first=Steven |last=Inglima |date=February 6, 2018 |website=photofocus |access-date=30 July 2024}} and early Edward Weston, though Weston was later credited with moving photography away from soft focus pictorialism.{{cite web |url=https://www.tate.org.uk/art/artists/edward-weston-2720 |title=Edward Weston 1886–1958 |website=The Tate Museum |access-date=30 July 2024}}{{cite web |url=https://magazine.urth.co/articles/edward-weston-photography |title=The Greats: How Edward Weston Pushed Photography into Modernity |first=Hudson |last=Brown |date=9 November 2020 |website=URTH |access-date=30 July 2024}}
The soft focus effect is used primarily in glamour photography, because it eliminates blemishes. In general, soft focus photography produces a misty, dream-like image, sometimes characterized as romantic.{{cite book |url=https://archive.org/details/techniquesofport0000hurt_z7r5/page/112/mode/2up |title=Techniques of portrait photography |first=Bill |last=Hurter |date=1983 |publisher=Prentice-Hall, Inc. |location=Englewood Cliffs, New Jersey |series=Master class photography |isbn=0-13-900621-4 |page=113 |quote=Soft focus or diffusion on the camera lens minimizes facial defects and can instantly take years off an elderly subject. Softer images are more flattering than portraits in which every facial detail is visible. Soft-focus images have also come to connote a romantic mood in portraits and pictorial photography.}}
=Technique=
Special focusing techniques may be required to use a soft focus lens. For example, a front-focusing technique was suggested for the Kodak Portrait, in which the point of focus was placed closer to the camera than the actual subject. Unlike typical camera lenses, which have a generally symmetric depth of field characteristic extending both in front of and behind the point of focus, the uncorrected spherical aberration results in a depth of field which extends past (behind) the point of focus, but not in front.{{cite web |url=https://alphaxbetax.com/wp-content/uploads/2022/09/1951-how-to-use-the-wollensak-portrait-veritar-lens.pdf |title=How to use the Wollensak portrait Veritar lens |date=December 1951 |publisher=Wollensak Optical Company |access-date=30 July 2024}}
Physically, the effect of a soft focus lens may be approximated by the use of diffusion filter or other method, such as stretching a nylon stocking over the front of the lens, or smearing petroleum jelly on a clear filter or on the front element or even the back element of the lens itself.{{cite book |url=https://archive.org/details/protechniquesofb00bern/page/6/mode/2up |title=Pro techniques of beauty & glamour photography |first=Gary |last=Bernstein |date=1985 |publisher=HPBooks |isbn=0-89586-364-2 |lccn=85-60457 |access-date=29 July 2024 |url-access=registration |page=7 |quote=An image can be softened with the use of a good diffusion attachment. In my beauty and glamour photography, the subject or client frequently prefers a soft-focus version. The diffusion can take place when the camera exposure is made, or later. ... I've achieved wonderful results with diffusers I made myself. As base, I use glass ultraviolet (UV) filters or sheets of acetate. On this base I spray commercial fixative in varying densities, depending on the degree of softening I want.}} The latter is less recommended because successive cleaning always introduces a risk to damage the lens's surface.
It can also be approximated with post-processing procedures, either during photographic printing or through digital manipulation. Specifically, highlights in an image are blurred, but the bokeh effects of soft focus cannot be reproduced{{Citation needed|date=August 2016}}.
=Design=
File:Appareil photo Vest Pocket Autographic Kodak 06.jpg
Because soft focus results from what are considered technical flaws, typically spherical and chromatic aberration, many older lenses had soft focus built in as a side effect of their construction. For example, the two-element cemented meniscus lens fitted to early Vest Pocket Kodak cameras had a dish-shaped hood{{cite web |url=http://www.earlyphotography.co.uk/site/entry_C89.html |title=Vest Pocket Kodak: 1912 |website=Early Photography |access-date=30 July 2024}} which controlled spherical aberration by reducing the effective aperture to {{f/|11}}; when the hood is removed, the resulting uncorrected images have a strong soft focus effect. After this modification, the lens enjoyed significant popularity in Japan during the 1970s, remounted to modern cameras.{{cite web |url=https://camerafan.jp/cc.php?i=302 |title=ベス単フード外し〜伝統のソフトフォーカスレンズ〜 概要編 |lang=ja |trans-title=Vestan hood removal ~Traditional Soft Focus Lens~ Overview |author=中村文夫 |date=October 21, 2014 |website=中古カメラ・マニアックス [Used Camera Maniacs] |access-date=30 July 2024}}{{cite web |url=https://camerafan.jp/cc.php?i=318 |title=ベス単フード外し〜伝統のソフトフォーカスレンズ〜 準備〜撮影編 |lang=ja |trans-title=Removing the hood of the Vestan lens ~Traditional Soft Focus Lens~ Preparation & shooting |author=中村文夫 |date=December 1, 2014 |website=中古カメラ・マニアックス [Used Camera Maniacs] |access-date=30 July 2024}} Photographers called this lens the {{Nihongo|Vestan|ベス単}}, referring to the camera's name and single-group lens construction,{{cite web |url=https://camera-kaukau.lekumo.biz/arrow/2011/03/vestan.html |title=ベス単フード外し |lang=ja |trans-title=Vestan hood removal |author=田中 長徳 |date=March 3, 2011 |website=Camera Kaukau |access-date=30 July 2024}} and the technique was championed by several Japanese photographers, including Shōji Ueda.{{cite web |url=https://fujifilmsquare.jp/en/exhibition/220630_05.html |title=Shōji Ueda Photo Exhibition 'Vest Pocket Sketches: White Winds: Brilliant Scenes' |website=Fujifilm Square |access-date=30 July 2024}} The basic design of this lens was revived in 2016 as the Yasuhara MOMO 100.{{cite news |url=https://dc.watch.impress.co.jp/docs/review/special/1013008.html |title=「ベス単フード外し」の再来か?安原製作所の新レンズ |lang=ja |trans-title=Is this a return of 'Vestan hood removal'? New lens from Yasuhara Manufacturing |author=大浦タケシ |date=August 2, 2016 |work=Watch-Impress |access-date=30 July 2024}}
Some lenses designed and sold during the heyday of soft focus lenses ({{circa|1910–1930}}), including the Pinkham & Smith Visual Quality series{{cite web |url=https://richardman.photo/2021/03/pinkham-smith-vq-iv-vs-cooke-portrait-lens/ |title=Pinkham & Smith VQ IV vs. Cooke Portrait lens |first=Richard |last=Man |date=March 5, 2021 |website=Richard Man Photography |access-date=30 July 2024}}{{cite web |url=https://www.cameraquest.com/pinkham_and_smith_visual_quality.htm |title=Mystry Pinkham and Smith Visual Quality #1 Series IV B Soft Focus Lens |first=Stephen |last=Gandy |date=January 27, 2022 |website=CameraQuest |access-date=30 July 2024}} and Busch Nicola Perscheid,{{cite web |url=https://www.barnebys.com/auctions/lot/busch-emil-nicola-perscheid-emil-busch-brass-lens-480mm-f4-5-goqyuv9kuh |title=Busch, Emil Nicola Percsheid - Emil Busch brass lens 480mm f4,5 |date=November 18, 2019 |website=Barnebys Auctions |access-date=30 July 2024}} were designed intentionally to take advantage of these flaws. As color films became available, well-managed spherical aberration became more desirable than chromatic aberration.
File:US4124276A (Okano Nakamura & Ogura, 1975).svg
Newer lenses are optimized to minimize optical aberrations, but starting from the 1970s, manufacturers began releasing specialized contemporary lenses which are designed with adjustable levels of spherical aberration at wide apertures. The effect can be disabled entirely as well, in which case the lens is sharp. These modern soft focus lenses and their effect on the images should be considered distinct from the effect of lenses designed to render smooth {{transliteration|ja|bokeh}} using an apodization filter, such as the Minolta STF 135mm f/2.8 T4.5.{{cite web |url=https://www.bhphotovideo.com/explora/photography/tips-and-solutions/what-is-apodization |title=What is Apodization? |first=Shawn C. |last=Steiner |date=June 19, 2019 |website=Explora |publisher=B&H Photo-Video-Audio |access-date=30 July 2024}}
As described in U.S. Patent 4,124,276,{{cite patent |country=US |status=Patent |number=4124276A |title=Soft focus lens system |invent1=Yukio Okano |invent2=Akyoshi Nakamura |invent3=Toshinobu Ogura |assign=Minolta Co., Ltd. |pubdate=November 7, 1978 |pridate=December 22, 1975 |fdate=December 15, 1976}} realized as the Minolta Varisoft Rokkor,{{cite web |url=https://www.pacificrimcamera.com/rl/00052/00052.pdf |title=Minolta Dealer Notebook, Part 4 (Lenses) |date=1981 |publisher=Minolta Corporation |access-date=26 July 2024 |via=Pacific Rim Camera, Reference Library}}{{rp|C9}} a modern example with variable spherical aberration is a six-element, five-group lens which can be divided into three composite lens groups, marked A-I, A-II, and B. The first four elements (A-I, closest to the object being photographed) are moved as a unit to focus the lens, increasing the meniscus-shaped air gap between A-I and A-II as the lens is focused closer. The air gap distance between A-II and B is used to control spherical aberration; spherical aberration increases as the distance between A-II and B grows. In the patent summary, the inventors noted the object side lens group (A-I) was a Tessar design, although they added that any suitable lens would do, such as a Cooke triplet or Double Gauss lens; the preferred embodiment uses two meniscus lenses on the image side to control spherical aberration.
File:BennyTrapp Imagon.jpg fitted with {{f/|7.7}}-equivalent sieve aperture.]]
As an alternative to variable element spacing, some soft focus lenses such as the Rodenstock Imagon use interchangeable sieve aperture "grid" or "diffusion" discs which have a perforated annular shape to control the balance of light recorded between the relatively well-corrected center of the lens and the uncorrected periphery. As light from the periphery is restricted, the soft focus effect becomes less pronounced. Effective aperture values (for computing exposure) range from {{f/|5.8}} to {{f/|11.5}}.{{cite web |url=https://www.cameraeccentric.com/static/img/pdfs/rodenstock_1.pdf |title=Imagon |date=September 1964 |publisher=Optische Werke G. Rodenstock |access-date=30 July 2024}}
Examples
Some examples of soft focus lenses, including modern (after 1950) lenses with controllable amounts of spherical aberration, include:{{cite book |url=https://archive.org/details/photographiclens0000unse/page/26/mode/2up |title=Photographic lens manual and directory |first=C. B. |last=Neblette |date=1959 |publisher=Morgan & Morgan, Inc. |location=New York, New York |lccn=59-11726 |edition=First |access-date=29 July 2024 |url-access=registration}}{{rp|27–28}}
;Notes
{{notelist}}
{{div col |colwidth=15em}}
- Kodak Portrait (4×5+)
- Leica Thambar 90mm {{f/|2.2}} (M39)
- Lensbaby Velvet 28 {{f/|2.5}}, 56mm {{f/|1.6}}, 85mm {{f/|1.8}}, and Trio 28 (multiple dSLR and mirrorless camera systems){{cite web |url=https://lensbaby.com/pages/velvet |title=The Velvet Effect |website=Lensbaby |access-date=30 July 2024}}
- Mamiya-Sekor SF C 145mm {{f/|4.0}} (M645){{cite web |url=https://ianbfoto.com/downloads/Mamiya%20645/Mamiya%20645%20145mm_Soft_Focus_Lens.pdf |title=Mamiya-Sekor SF C 145mm f/4 Lens for Mamiya M645: Instructions |publisher=Mamiya Camera Co., Ltd. |access-date=30 July 2024}}
- Mamiya-Sekor SF C 150mm {{f/|4.0}} (RB67){{cite web |url=https://ianbfoto.com/downloads/Mamiya%20RB67/Mamiya%20RB67%20150mm%20Soft%20Focus.pdf |title=Mamiya RB67: Mamiya-Sekor SFC 150mm f/4 Lens Instructions |publisher=Mamiya Camera Co., Ltd. |access-date=30 July 2024}}
- Mamiya Soft M 180mm {{f/|4.0}} D/L Variable Soft Focus (RZ67){{cite web |url=https://www.pacificrimcamera.com/rl/02519/02519.pdf |title=Mamiya RZ67 Professional IID |publisher=Mamiya Camera Co., Ltd. |access-date=30 July 2024 |via=Pacific Rim Camera, Reference Library}}
- Minolta AF 100mm {{f/|2.8}} (A/α){{cite magazine |url=https://books.google.com/books?id=E0MIEyyTY7MC&pg=PA22 |title=First Look: New Minolta lenses, too! |date=March 1995 |magazine=Popular Photography |page=22 |access-date=26 July 2024}}
- SMC Pentax-FA 28mm {{f/|2.8}} SOFT (PK){{cite web |url=http://kmp.pentaxians.eu/lenses/wide-angle/fa28f2-8-soft/ |title=FA 28/2.8 Soft |website=The Pentax K-Mount Page |access-date=30 July 2024}}
- SMC Pentax Soft 85mm {{f/|2.2}} (PK){{cite web |url=http://kmp.pentaxians.eu/lenses/short-tele/k85f2-2-soft/ |title=K 85/2.2 Soft |website=The Pentax K-Mount Page |access-date=30 July 2024}}
- SMC Pentax-F 85mm {{f/|2.8}} SOFT (PK){{cite web |url=https://www.snappiness.space/what-a-soft-focus-speciality-lens-does-to-highlights/ |title=What a Soft Focus speciality lens does to highlights |first=James |last=Warner |date=January 5, 2022 |website=Snappiness: The joy of photography |access-date=30 July 2024}}{{cite web |url=http://kmp.pentaxians.eu/lenses/short-tele/f85f2-8-soft/ |title=F 85/2.8 Soft |website=The Pentax K-Mount Page |access-date=30 July 2024}}
- SMC Pentax-FA 85mm {{f/|2.8}} SOFT (PK){{cite web |url=http://kmp.pentaxians.eu/lenses/short-tele/fa85f2-8-soft/ |title=FA 85/2.8 Soft |website=The Pentax K-Mount Page |access-date=30 July 2024}}
- SMC Pentax 67 Soft 120mm {{f/|3.5}} (P67){{cite web |url=https://skrasnov.com/pentax-67-120mm-f35-soft/ |title=Lens #6: Pentax 67 120mm F3.5 Soft |first=Sasha |last=Krasnov |date=June 13, 2021 |access-date=30 July 2024}}
- Petzval portrait (4×5+)
- Seibold Dreamagon 90mm {{f/|4}}
- Sima Soft Focus 100mm {{f/|2}} (T){{cite web |url=https://www.asahi-net.or.jp/~hw6k-asi/old-lens/old-lens-sima100.html |title=sima SF lens 100mm F2 (1982) |lang=ja |website=Omocame World |access-date=30 July 2024}}
- Spiratone Portragon 100mm {{f/|4}} (T){{cite web |url=https://reedphoto.com/old-school-meets-new-school-the-portragon-100-f4/ |title=Old-School Meets New School: The Portragon 100 f:4 |date=November 26, 2014 |website=Reed Photo |access-date=30 July 2024}}
- Tamron SP 70–150mm {{f/|2.8}} Soft (Adaptall-2){{cite web |url=http://www.adaptall-2.com/lenses/51A.html |title=Model 51A: Fast Portrait Zoom with Soft-Focus Feature 70~150mm F/2.8 |website=Adaptall-2.com |access-date=30 July 2024}}
- Wollensak Veritar (4×5+){{cite web |url=https://www.cameraeccentric.com/static/img/pdfs/wollensak_6.pdf |title=Wollensak Portrait Veritar Lenses |date=July 1950 |publisher=Wollensak Optical Company |access-date=30 July 2024}}
- Yasuhara Momo 100 43mm {{f/|6.4}} (multiple dSLR and mirrorless camera systems){{cite web |url=https://yasuharausa.com/products/momo100-lens |title=MOMO100 soft focus dreamy effect lens |website=Yasuhara USA |access-date=30 July 2024}}{{cite web |url=https://petapixel.com/2016/06/15/momo-soft-focus-lens-inspired-100-year-old-kodak-camera/ |title=MoMo is a Soft-Focus Lens Inspired by a 100-Year-Old Kodak Camera |first=Michael |last=Zhang |date=June 15, 2016 |website=PetaPixel |access-date=30 July 2024}}
{{div col end}}
=''Thambar''=
{{multiple image |align=right |direction=horizontal
|image1=Thambar.jpg |caption1=Very rare Leica soft-focus Thambar lens from the 1930s with original leather case. In front, left to right: Rear cap, special dot filter, lens shade, front cap.
|image2=Thambar portrait.jpg |caption2=A portrait taken with a Leica Thambar soft-focus lens}}
In 1935, Leitz released a legendary soft-focus lens, the Thambar 90mm {{f/|2.2}}, for the Leica rangefinder cameras. It was supplied with a special filter to block light through the center of the lens, resulting in the image being formed by relatively uncorrected aberrations through the periphery.{{cite book |url=https://archive.org/details/LeicaLensCompendiumE.Puts2005D.D.TeoliJr.A.C./page/n169/mode/2up |title=Leica Lens Compendium |first=Erwin |last=Puts |date=2005 |access-date=30 July 2024}}
It was made in small numbers, no more than 3000 units, and is a rare collector's item today.{{cite web |url=http://www.shutterbug.com/content/leitz-thambar-90mm-f22brwhy-it-considered-legendary-portrait-lens |title=The Leitz Thambar 90 mm f/2.2: Why Is It Considered A Legendary Portrait Lens? |first=Roger W. |last=Hicks |website=Shutterbug |date=1 April 2005}} In 2017, a new version was produced, costing $6,495. A lens from the original series can fetch between $3,000 and $8,000, depending on condition.{{cite web |url=http://www.overgaard.dk/leica-90mm-Summarit-M-f-25.html |title=Technical data on the Leitz Thambar f/2.2 |author-link=Thorsten Overgaard |first=Thorsten |last=Overgaard|date=17 October 2017 }}
See also
- Rodenstock Imagon
- {{Interlanguage link multi|Dreamagon|de|3=Dreamagon|lt=Seibold's Dreamagon}}
- Aberration in optical systems
- Lens (optics)
- Special effect
- Bokeh
- Convolution
- Depth of field
- Low-pass filter
- Gaussian blur
References
{{Reflist}}
External links
{{Commons}}
- [http://www.antiquecameras.net/softfocuslenses.html Soft Focus Lens Article]
- [http://www.largeformatphotography.info/soft-focus.html Soft-Focus Lenses and Techniques], an overview for large format photographers