The shutter limits the exposure time of the film or sensor, i.e. the time that is allowed for the exposure of the image window or sensor to take a picture. Basically, a differentiation is made between leaf shutters and focal-plane shutters and, in the case of digital cameras, the electronic shutter, which does not require mechanically moving parts. Hybrid solutions are also available for CMOS sensors. The exposure of the sensor is started with the shutter open and the exposure of the sensor is ended with the second shutter curtain.
With the first cameras, whose light-sensitive layer required a longer exposure time, the lens cap was often sufficient to control the exposure time by removing and replacing it. With increasing sensitivity of the recording materials, the first mechanical shutters were used. In digital photography, a dark phase is required to read out the sensor and to create a noise reference.
Terms and categories for a better understanding
• Mechanical leaf shutters (Copal 0/1/3)
• Electro-magnetic leaf shutters (Sinar/Leica eShutter 125, eShutter 250, H-lenses, certain Phase One lenses)
• Electronic shutters (sensor-based rolling shutter, as currently available in IQ3 100/Trichromatic and Hasselblad H6D backs; flash light not feasible)
• Global shutters (sensor-based "global shutter" are currently not yet available for large format sensors, flash light not feasible)
Overview photographic shutters in the ALPA system
From left to right: Copal 0, ALPA HR Alpagon 4.0/32 mm with Sinar/Rodenstock eShutter 250 (without control box), ALPA 12 FPS with Focal Plane Shutter, Phase One IQ 3 100 with electronic (rolling) shutter via sensor
A leaf shutters consists of several lamellas/blades and are similar in shape and construction to an aperture. In contrast to the usual aperture systems, however, the leaf shutter can be closed completely. Classically, thinly rolled steel is used as the material for the shutter blades. Carbon lamellas have also been used for some years. Hybrid material mixes are also used in some cases. These have proven themselves especially at high speeds for short exposure times. Most leaf shutters are used as so-called intermediate lens shutters. The shutter is installed at the point in the lens where the beam path is most concentrated. There, the required aperture requires the smallest diameter in each case. The smaller this diameter, the shorter the distance that the closure blades have to travel when opening and closing. With the smaller shutter blades, the moving mass can be kept smaller and a higher speed of the shutter itself can be achieved. The faster the overall sequence can be achieved, the faster the shutter speed that can be realized.
An important advantage of the leaf shutter is their short synchronization time. Sync speed is the fastest shutter speed at which a shutter opens the entire image field for exposure. A flash system that is triggered during this time window enables uniform illumination of the entire image.
For example, the synchronization time of current Phase One and Hasselblad central shutter systems reaches times of 1/1600 or 1/2000 second. Today, leaf shutters are mainly used for large and medium format camera systems in the field of image-based photography. In addition, leaf shutters are also installed in compact cameras such as the Fujifilm X100F. In practice, the disadvantage of having to install a central shutter as an intermediate lens shutter in each individual lens has no effect, as the lens cannot be changed. The shortest synchronous shutter speed for the X100F is 1/4000 second.
Manual No. 0/1
All information without guarantee.
Important care instructions for Copal shutters
• Only adjust times in uncocked status and never when the shutter has already been cocked (wear, damage to the escapement possible).
• Only full time increments can be set; never try to set split times (e.g. 1/45 second).
• Today's high-performance optics are NOT designed to exchange shutters freely and to screw in and out front and rear lens elements.
Who produced leaf shutters?
Mechanical leaf shutters were manufactured in Europe by Deckel/Compur/Prontor and until the 1990s by Gitzo in France. In Japan, Nidec Copal and Seiko/Seikosha were the most important manufacturers of leaf shutters. The last independent manufacturer of purely mechanical leaf shutters was Nidec Copal. The production of classic mechanical leaf shutters has since been discontinued. A transfer of the production by third parties failed due to the condition of the tools. Mechanical leaf shutters are no longer in production. Remaining stocks, however, are still available for some time.
The leaf shutters installed in lenses for medium format cameras today come from exclusive productions for the respective manufacturers. Sinar produces the eShutter with a shortest shutter speed of 1/125 second and the eShutter 250 with a shortest shutter speed of 1/250 second, which are also used by Rodenstock under its own name in Rodenstock lenses. Sinar offers the eControl control unit for its electromagnetical eShutter, which allows the eShutter to be used anywhere and without a computer. This makes it easier to use outside the studio. The Sinar eControl is the successor of the eShutter Control, which was introduced in 2012. Power is supplied by a rechargeable and replaceable lithium-ion battery. In contrast to the shutter, the control unit can be easily exchanged between different lenses. The respective lens is automatically recognized by the eControl and shown on the display. The desired aperture and exposure time can be set using a multifunctional wheel by turning and clicking. ALPA will introduce its own solution in 2018.
A technical alternative to the leaf shutter is the so-called focal-plane shutter. It is not installed in the lens, but in the camera body and therefore behind the lens. This was the reason for his popularity with the advent of camera systems with interchangeable lenses. The first focal-plane shutters were so-called cloth shutters, as they are still used in analog Leica M cameras today. Here a textile roller blind consisting of two closing curtains is moved horizontally. The sync speed is also in this case exactly the time in which the shutter is fully open. With faster shutter speeds, only one gap between the two curtains is released at a time ("scanning slit"). In newer focal-plane shutter models, the textile was replaced by thin metal foils. Later metal lamellas were used instead of roller blinds.
In the now mainly used metal lamella focal-plane shutters and their smaller space requirement, the flow direction of the closure elements changed from horizontal to vertical. This also shortened the distance to be covered by the shutter curtains for the mostly right-angled image formats. Seiko states 1/8,000 second as the shortest shutter speed for its 35mm shutters. The shorter distances also made it possible to shorten the synchronization time. With cameras in 35mm format, synchronization times of 1/320 second are now possible as standard.
In medium format cameras with their significantly larger image windows, the distances to be covered by the shutter curtains and the masses to be accelerated are significantly larger. This results in significantly longer synchronization times for focal-plane shutters compared to central shutters. Since this would have an even stronger effect on large format cameras, focal-plane shutters are not used there for this reason.
Changes to the requirements for a shutter
With the announcement of CMOS sensors for medium format cameras in January 2014 (Hasselblad H5D-50c and Phase One IQ250), the requirements for shutters also changed. In contrast to analog film and CCD sensors, CMOS sensors can be started with the shutter open (Life View). The shutter is only important here to stop the light stream to the sensor so that the complete sensor can then be read out without receiving new information. In addition, in the non-exposure state, the reference voltage of the sensor is determined, which is subtracted from the exposure data in order to take a correct picture.
The digitization of photography has brought another change in shutters. If one could simply unscrew the front and rear lens elements of a lens from the shutter at analogue times and then use the shutter in another lens, this is no longer possible today. One reason for this is the lack of housing stability of the shutters from the analogue period. Today the shutters are optimally adapted to the respective lenses and a shutter change would lead to a loss of the adjustment of the azimuth and the correct dimension of the aperture.
The Phase One IQ3 and IQ4, the Hasselblad H6D and X1D, so as many other mirrorless cameras today are equipped with an electronic shutter. The CMOS sensors available today do not read out simultaneously over the entire sensor surface. With these sensors, one can imagine a line with simultaneous start of exposure, which usually moves across the sensor line by line. With current medium format sensors, this takes about half a second. If the camera and subject are stationary, all pixels are exposed at their correct positions even with CMOS sensors, regardless of when they were exposed during the said half second. However, if images are taken of a moving subject or with a moving camera, the objects are displayed at their current location when the lines are exposed one after the other.
Since the mapping takes place line by line, the object has already moved from one line to the next to such an extent that, when all lines are combined, an object is displayed that was not mapped as a whole at once. Since the image is taken line by line at different times, a straight line in the subject can be bent or distorted. The use of flash units is usually not possible.
©David R. Liu
Rolling shutter effect is visible in the hand of the dancer. ©David R. Liu
Even if future sensors can be read out faster and it is therefore possible that electronic shutters in the version of the global shutter can also be used in medium format, a mechanical shutter will very probably still be required. This unit prevents the sensor from being exposed to light exposure if this is not intended in connection with a photograph. However, the shutter is then no longer necessarily used for the purpose of forming exposure time and it now takes on a new function as a protective element.
First published 06.2018, updated 06.2019
Have you always dreamed of advancing to the top league of macro photography? With the introduction of the affordable Fujifilm GFX 50R this is now possible. A universal, compact camera with 50MP sensor in 33x44 format and both fully electronic and mechanical focal plane shutter on a high-performance stacking solution from ALPA with high-end macro lens for large sensor. This is now becoming a reality with the connection ring for Fuji G cameras: The investment in a modular and universal system where the camera can always be updated cost-effectively with the latest system in the future.
The adapter allows easy and safe mounting of a Fujifilm GFX body to an ALPA bellows unit or stacking solution. The V-Groove version also allows a comfortable adjustment of the alignment/rotation of the camera body.
ALPA Adapter Ring Fuji G
Alpa Macro Switar 5.6/105 mm float
ALPA Castel Micro Focus Stacking
When we designed the ALPA 12 PLUS, the comparison with the Swiss cross quickly came up and thus the connection to the home country of the ALPA and the national flag with a white cross on a red background. Since a red camera was always associated with too much attention and imponderables during production - who wants red reflexes in the pictures - we decided to use two different color stitching adapters instead. And so there are two colour variants of the product: classic black and a new dash of red. And since we are introducing the adapters in the week of the Chinese New Year, this fits perfectly too.
The Stitching Adapter for the ALPA 12 PLUS is an accessory adapter that allows rise and fall movements The adapter has a built-in, universal, square dovetail adapter to UniQ/C standard for ALPA tripod heads and third-party products. The millimetre laser engraving 20/20 mm allows easy and convenient reading of the high and low adjustment, even behind the camera. The integrated mounting screw (1/4") is designed to be "loss-proof". It is available in black or red - you have the choice.
ALPA Stitching Adapter PLUS in red
ALPA Stitching Adapter PLUS in black
From March 24 to April 8, a solo exhibition of pictures by Chinese ALPA-photographer Chen Yewei will take place at the Inter Art Center in Beijing. The artists shows his photographic series "To the Peaks". For his work, he captured 14 of the world's highest mountains.
Born in the 1960s, Chen Yewei has been photographing landscapes and mountains in particular for over 20 years. He is the founder of the 40° Celsius Club and has been photographing with ALPA since 2008. The 40° Celsius Club derives its name from Chen Yewei's feeling of elevated body temperature, which sets in as he searches for the next picture. ALPA supports the gallery of the Inter Art Center in organizing the exhibition.
The Inter Art Center & Gallery in Beijing is considered one of the most important institutions for photographic art in China. Founded in 2006, the Inter Art Center includes the Pixel Magazine Publishing House, the Pixel Bookstore and a café. The Inter Art Center is dedicated to collecting and presenting classical photography as well as contemporary and experimental art.
In addition, the Inter Art Center has published a large number of illustrated books and books on photography. Its members have been working not only with numerous exceptional Chinese and foreign photographers and artists, but also with other institutions.
Focus on Minorities and Culture
Another focus of the Inter Art Center is the promotion of photography of ethnic minorities and the diverse development of Chinese culture. The Inter Art Center therefore founded the "Country Road: Chinese Ethnic Minority Photography Prize" in 2015 to discover, promote and support photographers who deal with social change and ethnic minorities. In 2017, the Inter Art Center New Documentaries Prize was launched in this context.
Internationally, the Inter Art Center maintains extensive co-operations with other photographic institutions such as the Maison Européenne de la Photographie in Paris, the International Center of Photography in New York and the George Eastman Museum in Rochester, New York.
Photographers page Chen Yewei
Inter Art Center
The ALPA eFinder II app gives photographers with an ALPA camera the opportunity to simplify their workflow and use their iPhone as a viewfinder. The app is a digital successor to the director's viewfinder, a device that lets directors determine the setting for a particular scene or shot. Thanks to the ALPA eFinder II App, locations and shoots can now be very easily explored and/or planned with the iPhone.
Photographers are able to define a setup for the desired subject from different ALPA cameras as well as any lenses. The photo frames of several different focal lengths can be displayed at the same time. Other features that ALPA has specially developed are shift simulation, parallax correction and an artificial horizon with compass readings (as a 3D spirit level). The GPS data for the photos can be stored, such that the locations examined can be retrieved at any time.
The eFinder app shows photographers exactly what they get with a certain setup for their picture. Together with the separately available holder, it can also be used as a fully-fledged viewfinder. The holder includes a wide angle converter. This simulates all ALPA wide-angle lenses, as well as those of other manufacturers, and shows a fully dewarped image.
Different frames show different focal lengths, which the user can select from the database. At the same time, picture-shifts can be simulated and parallax eliminated:
Picture without the wide-angle converter:
Picture with wide-angle converter and dewarping switched on:
The ALPA eFinder II app is a useful tool for new ALPA customers or those who are considering the purchase of an ALPA. Because the medium format of an ALPA has a different aspect ratio than a 35-mm camera. In addition, using the shift function allows photographers to use lenses that need to be slightly less wide-angle than in the case of 35-mm pictures. Because of the differences, new users are often not sufficiently aware which setup is the one suited to their subject. We therefore recommend that you familiarize yourself with the new factors that are present, with the eFinder.
Version 5.1 available via the App Store
The latest edition of the ALPA eFinder II app has of late been available from Apple's App Store. It was implemented, on behalf of ALPA, by Dire Studio. The latest version 5.1 for iOS 9.0 offers users two key improvements. On the one hand, the developer Laszlo Pusztai has created a new action window, which is used, among other things, to share shots via email or social media. In this way, photographers can get their pictures, for example, to their clients or project partners.
The new eFinder II 5.1 app’s "share" screen
The last version of the eFinder enabled up to five pictures to be sent via e-mail. With the new version, you can send a total of 20 pictures on devices running on 64-bit software and 10 pictures on devices with 32-bit software. This limit also applies to most other share functions and others still such as printing or copying – provided your service-provider has not set a lower limit of its own. New users can also send their pictures via AirDrop. This makes it particularly easy to transfer them from the iPhone to a computer. There is no upper limit.
The other important innovation is the removal of direct Dropbox support. At the end of June, Dropbox changed its interface to programming and removed the old version. Since hardly anybody used this function anyway, it was suddenly removed from the app. Users who want to load files onto Dropbox can do this directly with the normal Dropbox app, or auto-export parts of views to Photos, and then upload them from there using the Dropbox app.
"Turns the iPhone into a brilliant viewfinder"
The update to version 5.1 of the ALPA eFinder II app is available free of charge at the Apple Store for existing users. As an accessory, we recommend the above-mentioned iPhone holder with wide angle converter. This is available directly from ALPA - the wide-angle converter can also be ordered separately.
ALPA 12 SWA with mounted iPhone holder:
Overall, the ALPA eFinder App II is a practical and cost-effective tool that makes the planning process much easier for photographers. This is also shown by the response: specialist Henri Leuzinger has recently examined version 5.1 of the eFinder, for fotointern.ch, as part of his comparison of various professional cameras. He describes it as an "app, which makes the iPhone a brilliant viewfinder that can be adapted to almost all lens and shift functions".
More detailed information on the ALPA eFinder II App 5.1 can be found in the manual, which has also been updated. If you have any questions, we will be glad to answer them personally.
ALPA eFinder II App
ALPA SDH MkII iPhone Holder
ALPA aCam Wide Angle Converter for iPhone
Julian Calverley is a master of impressive landscape and commercial photography. He is using his iPhone as quick and simple but also creative complement to his ALPA cameras. Read the offprint of the UK magazine "Amateur Photographer", July 2014 with insight to his work with the iPhone and his love for ALPA. Julian also published a lovely little book with iPhone images only. His commercial work can be seen from his website, too. Julian was repeatedly selected for Lürzer's Archive for the 200 best ad photographs of the year.
Julian Calverley - Books: iPhone Only
Calverley - iShoot landscapes (PDF)
Photographers page: Calverley, Julian
ALPA is featured in an article in the special supplement "SWISSmade" which was distributed with several Swiss sunday papers from the 21st September 2014.
Passion and Perfection
Journée ALPA - Phase One le jeudi 27 novembre 2014
ALPA sera présent au Centre Pro, Profot de Renens (près de Lausanne/Suisse), en compagnie de Phase One, afin de vous faire découvrir toutes les nouveautés sorties à la Photokina.
Mlle Iris Sprow et M. Jean-François Zipper de chez ALPA vous dévoileront en particulier le nouveau système pour la prise de vue macro FPS.
Iris Sprow est diplômée du RIT Rochester en « Imaging Science & Photographic Technology ». Elle a fait son Master au London College of Communication en « Digital Colour Imaging » et travaille depuis 11 ans dans le domaine des médias appliqués dont 8 ans dans la recherche. Jean-François Zipper est diplômé de la FEMIS (École Nationale Supérieure des métiers de l’image et du son), Paris.
M. Massimo Saracino de Phase One vous présentera le nouveau dos IQ150 montré à la Photokina, une nouvelle fonction avec Capture Pilote de visée live direct sur un iPad avec les IQ2.., et bien sûr vous pourrez également explorer les nouvelles fonctionnalités de Capture One Pro 8.
Et enfin, M. Pierre-Alain Folliet Photographe, vous fera découvrir son travail réalisé pour la plupart avec le matériel exposé durant cette journée.
Nous vous donnons donc rendez-vous au Centre Pro Profot de Renens, le 27 novembre 2014 de 10h00 à 16h30.
Centre Pro Profot
Avenue de Longemalle 11
Tél: +41 (0)21 634 99 66
Website Profot: www.profot.ch
With the use of conventional camera systems and macro objectives, only a limited resolution could be achieved. That’s why ALPA developed a special setup for Focus Stacking. It’s a good example for our philosophy to provide solutions for special projects. Ask our specialists if you have a dedicated project.
Photographer Bernhard Schurian extensively tested the ALPA solution (ALPA Focus Stacking solution with ALPA 12 FPS and ALPA Macro Switar 5.6/105 mm) at the Museum für Naturkunde in Berlin. In addition to the mass digitisation of the collection, he has portrayed particularly interesting and spectacular animals. To document their complexity, Bernhard Schurian needed equipment for macro photography and an optimal workflow.
Here some results of his work over the last year and in different stages. Two samples are available as zoomable version (Zoom 1) (Zoom 2) for exploring. The images have been combined from in general some 500 to 700+ single exposures on 100 MP digital backs.
For further details see also the detailed news article on When Even Insects Become Huge: Macro Photography With ALPA.
It is our philosophy to provide new solutions for special applications. If you are working on an according photographic project, please contact us.
Photograph: ©Bernhard Schurian
Eumorpha Achemon (Zoom Version)
Photograph: ©Bernhard Schurian
Dipt Asilidae Microstylum (Zoom Version)
Photograph: ©Bernhard Schurian
Photograph: ©Bernhard Schurian
Of course, sophisticated professional camera photography has also been working digitally for a long time. ALPA was one of the most important pioneers in this process. The Swiss camera system ultimately offered the precision from the very beginning that the digital backs - almost in contrast to the roll film - only began to require over time. But until now, the actual technical/view cameras used the old mechanical Copal shutter, although its production was discontinued years ago.
Now also here the electronics take over. With the eShutter 250, Rodenstock and Sinar have developed a modern leaf shutter for view camera lenses as a successor, while Phase One and Hasselblad backs now allow access to the built-in electronic “rolling” shutter. Only when it comes to the photographic use outside of the studio, the ingenuity of the manufacturers has so far been rather limited. There were hardly practical solutions from the laptop to the huge control unit dangling down from the tripod. With the ALPA Silex Mk II this will change for the better now.
Here the trigger sits where it should be - on the side of the body, close to the hand grip - and the complete package with a robust housing made of two solid, milled aluminium halves is pleasantly compact, although even the 48V power supply for the eShutter has been integrated. In addition, this grip with brains can be rotated using the supplied Arri rosette adapters and the camera and back functions are always optimally visible.
The Copal shutter has been mourned a lot, but anyone who has ever worked with the eShutter will no longer want to do without it. Precise shutter speed setting, low vibration shutter operation, accurate repeatability, operation from the Silex control unit without having to open the shutter on the lens - photography with tilt, shift and stitch does not need to be cumbersome at all. And as long as the electronic shutters are not yet "global", there is no way around the electromagnetic shutter for flash photography.
ALPA Silex Mk II on ALPA 12 MAX and HR Alpagon 4.0/32 mm with eShutter 250
Silex - the grip with brains
Hasselblad H, Canon EF, Contax 645, Nikon E and Rollei lenses can also be controlled in this way. This is not only of interest for digital photography. Despite the electronic interfaces, the autonomous Silex offers the opportunity to make these lenses with built-in shutter as well as Rodenstock's professional lenses for analogue photography up to the 6x9 format fit for the future. Whether digital or analog - the Swiss precision tool will remain future-proof, not least through free firmware updates. Finally, the electronic (rolling) shutter of modern backs will certainly become even faster and triggering the eShutter directly from the LiveView without a rolling shutter is only a matter of time. Then the compact view camera becomes even more mobile.
ALPA Silex Mk II on ALPA 12 TC controlling a Hasselblad HC 4.5/300 mm
The Sound of Silex is the future.
Price and Availability
The ALPA Silex Mk II control unit is now available at a net price of CHF 3,897 (ex works Switzerland) from local ALPA dealers and ALPA in Zurich. Owners of the ALPA Silex Mk I can upgrade their units for CHF 685 (ex works Switzerland) to Silex Mk II.
ALPA Silex Mk II
Hardware Upgrade Silex Mk I > Mk II
Capture Integration Blog: ALPA SILEX MK II - The Technical Camera Powerhouse
ALPA Silex Mk II at Work
Behind the scenes © ALPA/Ralph Rosenbauer