Are modern ultrafast lenses useful?

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Very few high-end camera companies have delved into the sub-f/1.2 genre of lenses, even for digital. The likes of Canon and Nikon have played that game before, in the 1960s, and are too practical to make that mistake again. The only ultrafast lens produced by a camera manufacturer is the Leica Noctilux-M 50mm f/0.95 Asph. Made for digital cameras, it has been in production since 2008. But at US$13K it is hardly a lens for the masses.

“The reason to buy a high-speed lens is to allow shooting in low-light situations or with short shutter speeds. Your photos may not be super-sharp, but at least you get a picture. If you need the high speed, then this f/1.4 lens or an f/1.2 version are the ones to have. However, if you can accept a speed of f/2, which is still plenty fast, then the slower lens is sharper. As an added benefit, the f/2 lens will be less costly than a faster one.”

G.H. Smith, Camera Lenses: From box camera to digital, SPIE (2006)

If you compare the inside of a modern digital lens versus its vintage analog compatriot, the first thing you might notice it the extreme complexity found in the modern lens. Consider the two lenses shown below. The Nikon AI Nikkor 50mm f/1.2 hailing from 1978 has 7 elements in 6 groups. Spring forward to 2020, and the Nikon Nikkor X 50mm f/1.2 S has a mind-blowing 17 elements in 15 groups. It’s also almost three times the weight of its predecessor. Is the image better? That is really in the eyes of the beholder.

Of the dedicated, high-end, lens companies only Voigtländer really stands out. They make lenses for a number of varied camera mounts. For Micro-Four Thirds (MFT) they actually offer a range of f/0.95 aspherical lenses, 10.5mm (21mm), 17.5mm (35mm), 25mm (50mm), 42.5mm (85mm), and 60mm (120mm). There is even a faster f/0.8 29mm (58mm) lens. These in reality are made for crop-sensors, with their full-frame equivalents more in the line of f/1.9. If one were to create a MFT equivalent of the Noctilux-M 50mm f/0.95, you would need something along the lines of a f/0.5. There are also third-party companies producing “inexpensive” ultrafast lenses (often by means of innovative lens designs). For example the Venus Optics Laowa, TTArtisan, Mitakon Zhongyi Speedmaster, Meike, 7artisans all have f/0.95 optics in various focal lengths, and sensors sizes. In 2022 TTArtisan introduced an f/0.95 35mm lens for APS-C for US$200.

But I do wonder why there is such interest in f/0.95 lenses? Dreamy bokeh? Why not just make f/1.0 lenses? I mean there isn’t that much difference between f/0.95 and f/1.0 – like 1/7th of a stop. I imagine it’s a marketing spiel, just like I imagine it was for Canon when they introduced their 50mm f/0.95 lens back in 1961. It’s a gimmick in the same way that items that cost $1.99 are perceived as cheaper than those marked $2. Why not go even further? I mean Voigtländer do have their f/0.8 29mm (58mm) super aspherical for MFT, which they toute as a world first (as of 2021), and introduce in their literature as the “conqueror of the night”. It’s not the fastest 35mm lens every made either, that honour goes to the Carl Zeiss Planar 50mm f/0.7.

There are limits to what lens speed will do for photography. An f/0.95 lens already has a very small depth of field, so small it makes it hard to focus. Many of these lenses may not even be that usable fully open, requiring them to be stopped down to f/2 before any semblance of usability is invoked. Sure, great for low-light but how often does anyone need that? Too many people use these lenses just for the bokeh effect, but that’s another story altogether. Somebody must be buying the Leica lens, as they are still making it. Likely more people are buying the cheaper lenses, just to experiment with. Check out this review of the TTArtisan 50mm f/0.95 by Dustin Abbott, who describes one of the pros as being “fun in low light”, and ultimately maybe that’s how we should view these ultrafast lenses, for fun, creative photography.

P.S. I do own a MFT f/0.95, more by happenstance than anything else. A few years back I bought the original Voigtländer 25mm f/0.95 (used, not new) for my Olympus MFT camera. It’s an incredibly solid lens, but it’s shallow DOF does make it tricky to focus.

Vintage lens makers – Tewe (Germany)

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Tewe was a German company based in Berlin and well known for its long-distance lenses, up to 2000mm. Technische Werkstätten für Photo-Kinotechnik, Weiste & Co., TEWE OHG, was founded in 1935 in Schöneberg Berlin (in West Berlin during the Cold War period). The company initially developed long-focal length cinematic lenses, but by the 1950s and 60s they were producing long-focal length lenses for reflex cameras. Some of these lenses were designed in association with Astro-Berlin and Piesker. The company discontinued production in 1972.

Supposedly their lenses were used by astronomical observatories around the world, and lenses were well known for their “exceptional light intensity, unique brilliance, and needle-sharp, critical definition”. Their lenses were adapted for Exakta cameras, with lenses in the realm of 300-800mm.

Tewe Berlin Votar 500mm f/5
Some of the lenses produced by Tewe

These lenses were sold in two lens configurations, Telagon, or Telon. The Telagon had 4 elements in 3 groups, whereas the Telon was 2 elements in 2 groups. The Telon lenses were available in 400mm, 500mm, 600mm, and 800mm for 35mm, and a 1000mm for 6×6 cameras. The Telagon was available in 300/400/500/600mm. These lenses were heavy – the Telon 800mm was 6.5kg!

Which Fuji-X 16mm lens?

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The 16mm focal length for Fuji-X is the equivalent of a 24mm full-frame lens (if these things matter to you ). It’s the start of ultra-wide focal lengths, providing wide-wide without those fish-eye effects. It does give a more exaggerated sense of perspective, with subjects close to the camera appearing quite large, and the relative size of more distant subjects reducing with distance. If you are choosing a 16mm lens, what are the options? Well, just a few, two from Fuji, and another two from 3rd party companies. Three of these lenses sit around the same price point, while the fourth is more than double.

This is a good example of why choosing lenses can be tricky. Which one is best? Read any number of reviews, and you will get any number of differing opinions. Is more expensive better? I think it depends largely on what you want to get out of the lens. If this 16mm lens (24mm equivalent) is to be used extensively for travel, then the Fuji 16mm f/2.8 might be one of the best choices – it is compact and super-light (at 40% the weight of its f/1.4 sibling), it is weather-sealed, and inexpensive. It also gets an impressive amount of positive reviews. Its much pricier sibling, the wider aperture f/1.4 is heavier, but with the added bonus of having the closest shooting distance, and better performance in low-light.

Fujifilm 16mm f/1.4
R WR		Fujifilm 16mm f/2.8
R WR		Samyang 16mm f/2
ED AS UMC CS		Sigma 16mm
f/1.4 DC DN
Aperture range1.4 – 162.8 – 222 – 221.4 – 16
Minimum distance15cm17cm20cm25cm
Optical design
elements / groups		13 / 1110 / 813 / 1116 / 13
Lens design
length, ∅		73mm, 73.4mm45.4mm, 60mm115.8mm, 86.11mm92.6mm, 72.2mm
Weight375g155g615g405g
Weather sealingYesYesNodust, splash proof
Focusingautoautomanualauto
Made?JapanJapanSouth KoreaJapan
CostUS$999US$399US$359US$449
A basic comparison of 16mm lenses for Fuji-X

The Sigma 16mm offers the same wide aperture as the Fuji f/1.4, at half the cost. So for the cost-conscious it might be a good choice, but it is 20mm longer, and is built mostly from a Thermally Stable Composite” (TSC) polycarbonate material (both Fuji lenses have metal bodies). It also does not have an aperture ring, so the aperture needs to be controlled by the camera. Neither f/1.4 lens is compact, which makes sense – a larger aperture means more glass, and hence a larger lens. My final choice? The Fujifilm 16mm f/2.8. Why? I doubt I’ll need the speed of the f/1.4, and I like the lens’s light weight, and reasonable minimal distance focusing. And the price is nice.

What about 13mm or 14mm lenses? Well, that’s really a personal choice. They are equivalent to 19.5mm and 21mm respectively. It really is a matter of preference. A 13mm will provide 85° (hor) AOV, and the 14mm 81° (hor). If we compare this against the 16mm at 74° (hor) it provides marginally more angle. And there aren’t many options out there. Fujifilm has a 14mm f/2.8 which sells for US$900, and Viltrox has a 13mm f/1.4 for US$459.

Further reading:

Choosing the right digital lens can be challenging

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Choosing a digital camera, and a sensor size is one thing, but I think the thing that really stumps people is choosing the most appropriate lenses to use. Of course for the amateur photographer, what the lens will be used for may be the most important consideration. Travel? Landscapes? Street photography? The task is always made easier if there are some constraints on the number of lenses available. For example the range of lenses available for Micro-Four-Thirds, or even Fuji-X cameras has always been a little bit constrained, well until recently with the expansion of 3rd-party lenses.

So how do you choose the right lens? Like vintage lenses, digital lenses are principally chosen based on focal length (which advocates their use), and speed, i.e. aperture size. In addition there is cost, and “extras” such as weather sealing, and stabilization. The problem comes with the variety of lenses available – consider the long list of Fuji-X lenses, many of which are 3rd-party. Which one should you choose? Do you choose a prime or a zoom, a Fujifilm, or a third-party? Do you need an 8mm APS-C lens? Would 13mm be better? What about 16mm? Is manual focus okay, or would you prefer auto-focus? It’s not easy, even with the myriad of videos reviewing lenses.

I’ll concentrate on Fuji-X here, because it’s at the heart of my current lens dilemma (my camera is a Fujifilm X-H1). Now my photography is a mixed bag of street, landscape, architecture and travel. I currently have the 23mm f/2 R WR (which is a FF 35mm equiv.). Now I’m looking to expand, primarily a wide-angle lens. Here are some of the typical focal lengths for Fuji-X (APS-C sensor), and their applications. Measurements in ( ) represent the full-frame equivalences.

  • 50-56mm (75-85mm) – Good for portraiture.
  • 33-35mm (50-53mm) – Good for general photography, portraiture and cityscapes.
  • 23mm (35mm) – The upper end of the wide spectrum, provides more scene than the 33mm, but without the distortion of wider focal lengths. Good for street photography.
  • 18mm (28mm) – The standard choice for landscapes (and sometimes architecture), providing a relatively wide angle of view, without introducing obvious distortions.
  • 14-16mm (21-24mm) – The common lower end of the wide spectrum, good for very broad landscapes. Can include some noticeable perspective distortion, especially if the camera is tilted.

Beyond that we begin to move into the ultra-wide focal lenses, of which there seem to be quite a number. 11-13mm (16-20mm) lenses encompass more of the scene than can be seen with normal vision, so there is an innate sense of exaggerated perspective. Subjects close to the camera appear quite large, with the relative size of more distant subjects reducing quickly with distance. These lenses can be ideal for photography where the distortion does not impact the aesthetics of the image.

Various Fuji (APS-C) lenses and their associated angles of view. (Photo taken from Belvédère Kondiaronk lookout on Mont Royal, Montreal)

In reality, going down this rabbit hole has led me towards the 16mm, and possibly something like a 33-35mm. I have enough vintage lenses to cover the 50mm+ spectrum, and this makes sense as I don’t envision using them that often. And I’m going to stick with prime lenses. Some people really like zoom lenses because of the flexibility they allow, but I find I always seem to stick to one focal length – the 12-40mm on my Olympus camera used when travelling is perpetually set at 12mm (24mm). There are other compromises as well – weight can be an issue, as well as slower apertures.

Choosing a digital lens is challenging, especially for the hobbyist photographer. There are a lot of options, regardless of the sensor. Even Micro Four Thirds also has a long list of lenses. If someone is unsure, then I suggest starting with lenses from the camera manufacturer. As to focal length, choose a lens that provides the most optimal angle-of-view for the application you are most interested in. For example, if you shoot with an APS-C camera, and your focus is street photography, then a 23mm (35mm) lens is the most optimal solution.

Are wide-angle lenses the new “normal” ?

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As I have mentioned before, the standard Angle-of-View (AOV) of the human visual system (HVS) is about 60° (horizontally) – the central field of vision, so to speak. So why do companies still tout 50mm lenses as being “close to the angle of view of the human eye”? It’s honestly hard to know. Zeiss still describes its Touit 32mm f/1.8 as offering “…the same angle of view as the human eye.“, with a horizontal AOV of 40°. The dominant “standard” lens for full-frame has been the 50mm since the introduction of the Leica by Barnack in 1925. That’s nearly a century of using a lens that doesn’t really duplicate the AOV of human vision, mostly because it simplifies human vision far too much. It doesn’t even match the 43.3mm diagonal of the 36×24mm frame – which is normally the golden standard of a “normal” lens.

A 50mm lens has a horizontal AOV of 39.6°, which only comes close to representing the region of the HVS that deals with symbol recognition, which is a somewhat narrow scope. In fact, most people aren’t really concerned about whether they are using a lens that “approximates human vision”. One of the most talked about lenses in the Fuji-X environment is the 23mm lens, which is close to a 35mm in full-frame land. In all likelihood, there has probably been a gradual move away from 50mm towards the wider focal lengths. For example the iPhone 14 has two rear facing cameras: a 13mm ultra-wide, and a 26mm wide (equiv). No 50mm at all. With a wider AOV it is possible to crop from within the frame.

What a 28mm iPhone camera lens sees (orange) versus the smaller AOV of a 50mm lens (blue)

Some would probably advocate for the actual diagonal of a full-frame, i.e. 43mm. This would give an AOV of 45°, midway between 30 and 60 degrees. But is this optimal? I think it comes down to personal preference. I personally think that a 60° is likely a better approximation for a lens. So which lens better represents the 60°? For full-frame it is likely around 31mm, or around 20-21mm for APS-C. So we end up in the spectrum of wide lenses, and that’s not necessarily a bad thing. Humans visualize the world around them in terms of a wide lens – yes not all of it is in complete focus, but then the HVS works in much different ways to a camera lens.

Further reading:

Vintage lens makers – Steinheil (München)

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C.A. Steinheil & Söhne is the oldest of Munich’s optical companies, founded in 1854. It was established by Carl August von Steinheil (1801-1870), who was a physicist, astronomer, mathematician, and engineer. The company manufactured telescopes, spectroscopes and photometers. Over time this was supplemented by the production of optical glass.

During one period there was a great indignation against adulteration of Munich beer by greedy brewers. In the early 1840’s Steinheil designed a “beer lens”, a triplet that consisted of two glass lenses, in the middle of which was a fluid lens, a tiny quantity of the beer. The gadget showed impurities by means of spectral comparison. This was known as the optico-areometric beer test, and was based on the connection between the light refracting power of the beer, and its constituents.

By the end of the 1930s the company had been renamed Optische Werke C. A. Steinheil Söhne GmbH. In 1954 the name Steinheil was trademarked in the USA. In 1962 the company was sold to the Elgeet company in Rochester (NY), followed shortly after in 1964 to the aviation conglomerate Lear Siegler in Santa Monica. This resulted in a decline in the manufacture of commercial lenses in favour of aerospace/military applications.

From the 1940s through to the 1970s, the company produced a myriad of lenses for Exakta, M42, and Leica mounts. Many of the early lenses had the classic chrome finish of the period. By the mid-1960’s Steinheil dumped the chrome finish in favour of black enamel finishes typically with a striped focus ring. Examples include Quinaron, Quinon, Quinar, Tele-Quinar, Culminar, Cassar, Cassaron, Culmigon, Cassarit, Macro -Quinaron, Macro-Quinone, Macro-Quinar, Macro-Cassarite, Exagon, Tele-Exaktar. Some examples include:

  • Auto Quinaron 35mm f/2.8 – extreme close focus to 11cm.
  • Auto Tele-Quinar 135mm f/2.8 – exceptional mid-range lens, aperture down to f/32, and a minimum focus distance of 12.5cm.
  • Tele-Quinar 200mm f/4.5 – excellent preset telephoto, aperture down to f/32, chrome body, 14-blade aperture.

B&W versus colour

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“In black-and-white the photographer has to translate in his mind’s eye the colours of his subject into a range of tones before he presses the trigger, and that effort alone makes black-and-white in a way more creative than colour. It paraphrases and formalizes more. Structure, texture, and rich tonal quality are all weakened by colour, for colour tends to distract the eye from strong forms and their pure architecture. A decorative prettiness may be gained by colour, and sometimes emotional force too, but drama is often lost, not least the drama of a significant instant of action which will never recur. Light in its various moods has deep emotional meanings for everyone, and black-and-white can often convey those meanings more powerfully than colour.”

Eric de Maré, Color Photography (1973)

The myth of the 72ppi web image

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So when people create images for the web they are often told that the optimal resolution is 72dpi. First of all, dpi (dots-per-inch) has nothing to do with screens – it is used only in printing. When we talk about screen resolution, we are talking about ppi (points-per-inch), so the concept of dpi is already a misinterpretation.

There is still a lot of talk about the magical 72dpi. This harkens back to the time decades ago when computer screens commonly had 72ppi (the Macintosh 128K had a 512×342 pixel display), as opposed to the denser screens we have now (to put this into perspective, it had 0.175 megapixels versus the 4MP on the 13.3” Retina display). This had to do with Apple’s attempt to match the size of the graphics on the screen to the size when it is printed. The most common resolution of the bits of a bitmapped image on the screen of a Macintosh was 72dpi. In a 1989 InfoWorld article (June 19), a review of colour display systems mentioned that “… the closer the display is to 72 dpi, the more ‘real world’ the image will appear, compared with printed output.” This was no coincidence, as Apple’s first printer, the “ImageWriter” could produce print up to a resolution of 144dpi, doubled the resolution of the Mac, so this made scaling images easy.

Saving an image using 72ppi makes no sense, because it makes no difference to what is seen on the screen. An image by itself is just a quadrilateral of pixels, it has no context until it is viewed on a screen or printed out. Viewing devices have pixels that don’t change unless the resolution of the monitor changes. This means how an image is displayed is dependent on the resolution of the screen. For example, a 13” MacBook Pro with Retina screen has a size of 2560×1600 with a resolution of 227ppi. This means an image that is 4000×3000 pixels will take up 17.6×13.2” – it would be much larger than the screen if displayed at full resolution. When these images are opened on the laptop they are generally displayed at around 30% of their size, so that the entire image can be viewed.

A 12MP image overlaid on various screen sizes (the white rectangle). The size of the pictures have been modified based on the ppi of the screen.

Most webpages are designed in a similar manner, and auto-adjust image sizes to fit the constraints of the webpage design template. It also shows why 12MP or even 6MP images really aren’t needed for webpages. If we instead reduce the spatial dimensions of a 12MP image by 50% we get a 2016×1512, 3MP image – which would only take up 8.8×6.6” of space on the screen (illustrated below). Less screen space is needed, and the smaller file size will benefit things like site loading. If a 6 or 12MP image were used it will just be a larger image to load, and will resized within the webpage by the browser.

Two different sizes of an image in relation to a screen which has a resolution of approximately 4MP: a 12MP image which is too large for the screen (left) and an image which has its spatial dimensions reduced to 50%, which fits inside the screen (right).

What about viewing an image on a 4K television? 4K televisions all have a resolution of 3840×2160. The only caveat here is that if the size of the television changes, the ppi also changes. A 50” TV will have a resolution of 88ppi, whereas an 80” TV will only be 55ppi. This means the 2016×1512 image will appear to be 23×17” on the 50” TV, and 37×27” on the 80” TV. It’s all relative.

So changing an image to 72dpi has what effect? Basically, none. You cannot change the ppi or dpi of an image, because they are dependent on the screen, and printer respectively. So modifying this field in a file to 72ppi/dpi makes no difference to how it is viewed on the screen, or printed on a printer. No screens today have a resolution of 72ppi, unless you are still using a 1980s era Macintosh.

An image which is automatically resized in a webpage, versus the actual image (right).

Eric de Maré on seeing

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“What is reality? The very act of seeing is to a large degree creative, for we never perceive reality as such, nor can we ever do so. Seeing is the result of training from birth and of the effects of the cultural inheritance of that training. The mind created images from the rough, raw material of the light waves picked up by the optic nerves and transmitted upside-down to the brain, where it is transmuted, the right way up, into significant forms which help us to survive.

From the very limitations of all our senses we are able to create a human world from the chaos of that so-called reality which we do not, and may never be able, fully to comprehend. Seeing is too often taken for granted, but it is by no means the simple, obvious activity it is generally taken to be. It is, indeed, the most extraordinary and inexplicable mystery.”

Eric de Maré, Colour Photography

Vintage lens makers – Astro-Berlin (Germany)

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Astro-Optik is one of a number of German optical companies that flew under the radar, due to its speciality lenses. It was founded in 1922 as Astro-Gesellschaft Bielicke & Co and based in Neukölln, Berlin (which would become part of West-Berlin). The founders were William (Willy) F. Bielicke, Hugh Ivan Gramatzki and Otto (?). Gramatzki (1882-1957) was a successful amateur astronomer and astrophotographer who published in the journal Astronomische Nachrichten, and headed the local branch of “Berliner Astronomische Vereinigung” for a number of years. Gramatzki invented the Transfokator in 1928. Bielicke (1881-1945) a German-American optical designer was involved in the technical development of the lenses and was responsible for the “Tachar” and “Tachon” lenses.

The 1000mm lens

So it is then not surprising that Astro-Berlin’s product range included lenses suitable for astrophotography and astronomical photometry. After the war the company focused on its film technology (Astro-Kino, Astro-Kino Color) developing lenses that had long and extremely long focal lengths, sometimes called “optical heavy artillery”. The company ceased operations in 1991.

The company produced a multitude of lenses, many under the brand Astro-Berlin. Astro-Berlin is likely most famous for its long lenses for cinematography and photography. These lenses were very simple consisting of one (f/5, f/6.3) or two (f/2.3) achromatic doublets. The f/5 lenses for 35mm came in 300mm, 400mm, 500mm, and 640mm lengths. The 800mm f/5 lens was designed for medium 60×60mm format, and the 1000mm f/6.6 for 60×90mm format.

mm12515015020030030040050050064080010002000
f/2.32.31.83.53.5554.55556.310
Focal lengths (mm), and apertures of Astro lenses for 35mm/6×6 reflex mounts

In addition they produced quite fast lenses. In 1933 they introduced the Tachor f/0.95 which was available in various focal lengths. The 75mm version was suitable for an 18×24mm format (half-frame) but it was a large lens at 110mm in length with a frontal diameter of 81mm. The longest lens produced was possibly the 2000mm f/10 Astro Telastan. At times Astro also cooperated with the other Berlin optics manufacturers Piesker and Tewe.

Ads from Das Atelier des Photographen (1936)

These days, Astro-Berlin lenses are expensive on the secondhand market. For example the Astro Berlin Pan Tachar 100mm f/1.8 can sell for up to C$6000 depending on condition. However it is possible to find a 500mm f/5 lens for between C$900-1200.

Further reading: