Thambar is a magical lens that can make objects levitate.
In the Middle Ages, nobles had portraits of themselves and their families painted by artists. With the invention of photography, common people were also able to have their portraits taken. However, the equipment was still expensive, and they had to rely on specialized photo studios. Since the need for portraits has existed since ancient times, lenses developed for portraits have been around since the dawn of photography, and their designs were mature. These lenses were applied to Hollywood, and soft focus was established as a powerful photography technique. It was also applied to still images. One example is the 90mm f2.2 soft focus lens "Thambar" developed by the German company Ernst Leitz for Leica cameras in the 1930s. Before the war, it was still expensive, about the price of a house by Japanese standards at the time, but it is said that more than 3,000 were produced in total.
Germany's Reitz Company, Thambar
Because the bokeh was so unique, few lenses in later generations inherited its design concept. (Tamron SP70-150mm f2.8 SOFT, designed by Eiichi Takano and announced at Photokina in 1980, is an amazing lens that allows you to adjust the zoom and softening amount, but the softening effect of this lens is the same as that of the Tambor. It may be that they studied older lenses. Takano laterKiyohara soft copy of the best pocket Kodak lens was designed). People often complain that the background is noisy. They say that if you don't choose the background carefully, the image will look ugly. Most soft focus lenses are made to blur the subject beautifully from behind. On the other hand, Thambar creates a beautiful blur towards the front.
Thambar optical design
The most famous photograph taken with a Thambar is probably "那覇の芸者 Geisha of Naha" taken by the leading Japanese photographer 木村伊兵衛 Kimura Ihei during his trip to Okinawa in the 1930s. In this photograph, the subject stands out, a characteristic that can be seen in any portrait or Kino lens.
木村伊兵衛 Kimura Ihei "那覇の芸者 Geisha of Naha"
How clear were 19th century photographs? We can still compare old photographs (and buy them at auctions), but there was a range of clarity. There was the old method of polishing by hand without any geometric calculations, and the other method of carefully designing and precisely manufacturing based on calculations. The latter method gradually became mainstream and is still used today, and this trend led to the development of lenses that could take high-contrast, sharp photographs. Lenses that could produce clear images all the way to the edges of the image were considered superior, and such lenses were used in silent films in the early 20th century. (Landscape photography lenses from this era were breathtakingly beautiful, so it's no wonder they were highly valued.)
However, the soft style was introduced in the 1910s, and soft focus was originally a technique used in still photography, but was adapted and used in film, mainly for close-ups of people. Everything was tried: covering the lights and lenses with various materials such as silk or gauze, smoking with dry ice, developing the film to reduce contrast, and even buying soft filters, which were just starting to appear on the market. Soon, people began making special equipment and lenses just for soft focus, trying to find a way to achieve the effect.
Specialized lenses had features that surpassed all other methods of soft effects in film that had been thought up until then. They could project the image of the main character clearly. Methods other than specialized lenses either blurred the entire screen or there was no clever way to avoid that, but special lenses for soft effects could softly envelop the heroine without losing her delicate outline, and had the advantage of being able to change the depth of field and the degree of blur by adjusting the aperture. The aim was to clearly separate the character from the background and draw people's attention to the facial expression that emerged beautifully on the screen. Soft effects were impossible to achieve with anything other than specialized lenses.
This means that soft tuning cameras for Kino existed from the beginning of the 20th century. However, they were not commercially available. They were said to have been custom-made by individuals, and the number produced was extremely small, probably only made by people associated with Hollywood, so perhaps it was inevitable that none survive to the present day. There were commercially available cameras for large-format photography, but none for small cameras, so the Thambar, designed by Max Berek of Leitz, could be said to have been a historic breakthrough.
After the release of the Thambar in the 1930s, the field of soft focus was largely ignored. As film photography made various advances, soft focus lenses fell out of use, but I think this was due to a lack of funds to purchase special soft focus lenses for still photography. Eventually, soft lenses made a comeback when cheaper Japanese products were released, but I think these were intended for landscape photography rather than portrait photography. In Japan, soft lenses such as the Vestan have a tradition of being used for landscape photography, so perhaps these lenses were made with that in mind.
Optical design of Hanakage S1
花影 Hanakage S1 60mm f2.2JPY 125,000
Only brass stripped (gold) in stock
To achieve the effect of a soft focus lens, spherical aberration is mainly used. Sometimes chromatic aberration is added to this. Thambar almost completely corrects chromatic aberration. This is probably because color film became popular around this time. The effect is achieved with spherical aberration alone. Thambar overcorrects by +3. The amount is probably determined by stopping down the aperture by one stop. The degree of softening changes depending on the environment, such as the surrounding light conditions, so there is no always best position, but it is designed to achieve a moderate effect by stopping down by one stop. If you shoot this in a direction that tries to maximize the softening effect with the aperture open, the focus will be shifted because the effect is achieved by increasing the aberration. The spherical aberration diagram below shows the shift as shown in the left figure with the aperture open. The closer the subject, the more noticeable this shift is. Since f2.8 and below are the main focus, it is about 0.75 higher, but there is still some shift. This can't be helped, so the real Thambar also has this problem. So the image in the middle is the one with the entire optical section moved forward by 1mm, and it is well focused at around f2.8. However, if you narrow it down more than f4, it will no longer be in focus. However, in the case of the Thambar, it is 90mm, so it is a little more gentle. If you move the optical section forward by another 1mm, it will become the image on the right, and it will be in focus near the maximum aperture, but this is not often used. The image in the center of the image is the Hanakage S1. Therefore, it is focused a little forward. If you still use a Leica, I would like you to trust the rangefinder when shooting. Otherwise, the entire image will not be soft. If you are shooting while checking the LCD screen, please use this as a reference and adjust the amount of adjustment.
Spherical aberration diagram of Hanakage S1
The world's first soft focus lens was released in 1893 (the year the triplet was invented) by the British company Dallmeyer, which hired photographer Bergheim as an advisor and released it for large-format cameras in 1896. This lens allowed adjustment of the soft effect. Dallmeyer had already made the world's first lens that allowed adjustment of the effect by moving the lens spacing. However, other manufacturers were reluctant to adopt this simple mechanism, and subsequent lenses did not include the soft adjustment function. I think this was because there were problems with the quality of the soft effect. Since the aberration arrangement would change, it would have been difficult for manufacturers who wanted to sell beautiful effects that surpassed those of their competitors to accept it. I think this was because it was professional equipment. As time passed, cheap Japanese products became the norm and most buyers became general consumers, so I think the adjustment mechanism was revived with an emphasis on performance and versatility.
Another notable feature about the classic Thambar technique is the presence of a special filter. The softening effect of the Thambar weakens the more you stop down the aperture. In other words, the effect is mainly achieved by using the aberration around the periphery of the lens, but if you hide the good performance part in the center, you can expect an even greater effect, so a filter that blocks light from passing through the center is included. Since the amount of light entering the lens is reduced, it is necessary to change the aperture, and two scales are written for when the filter is not used and when it is used.
Two f-stops engraved on the Thambar
However, this is actually thought to be a measure to deal with the annoying background blur, rather than to enhance the softening effect. The softening effect is sufficient without using a filter. On the other hand, when a filter is used, the unevenness of the background blur is reflected in the shape of the center of the filter, making it round and neat. In still photography, a dirty background can make it difficult to create a work, so it is natural to think of this as a response to that. This method is not used in large-format photography, and instead spherical aberration is slightly undercorrected and chromatic aberration is mixed in to prevent unevenness in the background (See German Patent DE372059. This patent was published about 10 years before the Thambar was released). Even in the same portrait, Berek under-corrected the spherical aberration in the Hector. However, if it was significantly more positive, it would have been necessary to deal with the dirt in the background, which is why he may have added the filter. However, this filter is tricky, and although it clearly improves the bokeh, it looks arbitrary and lacks naturalness. The effect is cheap. Kimura Ihei often uses Thambar in portrait photography, including the aforementioned work, but he did not like this filter and did not use it. It may be easier to understand if you think that the reason why many people dislike mirror lenses is similar to the reason they use filters.
The Thambar lens configuration is unique, and Berek eschews the traditional idioms of large-format portrait photography, as well as Petzval and RR configurations. Berek himself has studied and admired Petzval's original design, but at least his own designs do not appear to remain. This approach is very similar to that of Bielike of Astro Berlin. Bielike applied for and received a Petzval patent during his apprenticeship, so he must have studied the possibilities quite a bit, but he has not touched this configuration since his Berlin days. Like Berek, he values Triplets and Gauss. His treatment of Ernostar to Sonnar
type is also similar.
木村伊兵衛 Kimura Ihei "那覇の市場 Naha Market"
Kimura saw the market in Naha and wanted to shoot it like a movie, so he decided to shoot this piece. If he hadn't had a Leica lens, he might not have come up with the idea.
The green part in the image below is the hood, which is removable. I don't recommend taking pictures with the hood removed, especially with digital cameras. I think it's absolutely necessary. The diameter is 40.5mm.
Hanakage S1 lens barrel design drawing
I wanted to make the lens of the Hanakage S1 60mm (58mm to be exact) and have the same characteristics as the Leica Thambar, but it was impossible to make it that short. Since the lens structure itself is telephoto, if I wanted to shorten it, I would have had to increase the number of layers like the Hector 50mm. However, if I gave up and made it 90mm, the applications would be limited, so I considered canceling it. I thought about making another model, but I thought that if it was okay to have Kino (movie)-like aberrations, this would be better than the real thing, so I decided to make it. Since the lens structure is the same, it has an elegant bokeh like the Thambar, but the spherical aberration is suppressed to plus 3 at 58mm, so it is not as soft as the real thing. In reality, it should be about 4.5, but I thought that such strong softness would not be usable. I don't think there is any other high-end lens in the history of optics that produces such beautiful colors.
Germany's Reitz Company, Thambar
Thambar optical design
木村伊兵衛 Kimura Ihei "那覇の芸者 Geisha of Naha"
Optical design of Hanakage S1
Spherical aberration diagram of Hanakage S1
Two f-stops engraved on the Thambar
木村伊兵衛 Kimura Ihei "那覇の市場 Naha Market"
Hanakage S1 lens barrel design drawing