Tag Archives: photography

Experiments in Photogrammetry

Recently we experimented with producing a set of 3D models of items from the collection using a process called photogrammetry. Rose Attu, a Digital Humanities MA Student from UCL, who’s currently on placement at the BPMA, talks us through the process.

To create a 3D model a series of overlapping photographs of a single object are taken from different positions, and then a piece of software is used to triangulate the coordinates of each image and align them, reconstructing the whole object in 3D. With each shot, the digital camera also records metadata including the focal distance between the lens and the object; this enables the software to recreate the position the camera was in when each photo was taken.

Curator Emma Harper holding the stamp snake

Curator Emma Harper holding the stamp snake

The objects we chose were the prosthetic Postman’s Hand and the Stamp Snake. An object covered in a repeating pattern, or one without any distinguishing features at all, will affect the software’s ability to rebuild the depth of an object. Both these objects have plenty of distinctive features, so the software could detect the details from photo to photo and build accurate models without distortions.

Postman's prosthetic hand being photographed

Postman’s prosthetic hand being photographed

Our first object was the Postman’s Hand. Once it was in frame and in focus, and evenly lit to avoid shadows, we could begin the capture process. To capture our objects from multiple angles we used a turntable to rotate them through 360°. The turntable was also covered in a distinctive image, which gave the software more common points to identify. The turntable was edited out at a later stage, so that our final models were just of the hand and the stamp snake.

Stamp snake being photographed

Stamp snake being photographed

On average it took 30 photos to complete one rotation, after which the camera was raised for a second sequence capturing the object from a higher angle. For more consistent results we kept the camera settings the same until a rotation was complete, and used a tripod and remote shutter release to keep the camera static. We output the raw image data as a set of TIFFs and corrected the white balance, and then our images were ready to be transformed.

Based on the estimated camera positions and the details in the images, the software built a point cloud, which is essentially a 3D model made up of dots. It then added a more detailed polygonal mesh layer representing the object surface. The final step was to add the textures; because we photographed our objects in high resolution, even the tiniest details were visible on the final models.

Snapshot of the 3D model of the stamp snake. Manipulate the model on Sketchfab.

Snapshot of the 3D model of the stamp snake. Manipulate the model on Sketchfab!

We were surprised with how little effort and technology it took, and the results were fantastic!  For our set-up we used:

  • Lazy Susan turntable with a nonrepeating pattern on it
  • Digital SLR camera and tripod
  • Light box or tent
  • Studio lights or some source to help get rid of shadows
  • Photogrammetry software – we used Agisoft which was great and you get a 30 day free trial

Have a go yourself– we would love to see your models!

– Rose Attu

Stamps: Why the Portrait?

As an Art Historian (now Philatelic Assistant) I have always been fascinated by the portrait and a stamp in itself is a miniature piece of art. To understand why the Queen’s head appears as it does on GB stamps we need to first understand the significance of the portrait historically.

Some of the earliest profile portraits were produced by the Romans for their coins and medals.  Images of the Emperors illustrated their power and importance and thus the profile became synonymous with these characteristics. It was also a way of distributing the face of their leader, who many would never have seen.

Roman Coin

Roman Coin

We can see the influence of these artefacts in the work of Renaissance artists who tried to recreate this sense of power in their portraits of the wealthy. This is evident in the portrait of the Duke of Urbino and his wife by Piero della Francesca who are both depicted in profile facing one another. Yet this composition had to be used as the Duke had previously lost his right eye in a tournament. You can also see the significance of the medal in Sandro Botticelli’s ‘Portrait of a Man with a Medal of Cosimo De Medici’ c.1474-75.

Piero della Francesca 'Duke of Urbibo' c1467-1470

Piero della Francesca ‘Duke of Urbino’ c.1467-1470

Sandro Botticelli 'Portrait of a Man with a Medal of Cosimo the Elder' c1474-75

Sandro Botticelli ‘Portrait of a Man with a Medal of Cosimo the Elder’ c.1474-75

However the initial portrait of Queen Elizabeth II used for postage was not in fact a profile. Instead it was a three quarter view of Her Majesty photographed by Dorothy Wilding in 1952. Though adequate as a Definitive stamp –  the Wilding design was found to be overly challenging for many stamp designers as it took up to one third of the stamp’s area and subsequently compromised the design of the stamp.

Wilding High Value Definitives 1955

Wilding High Value Definitives 1955

As a solution to this problem Tony Benn (Post Master General 1964-66) along with designer David Gentleman introduced the idea of removing the Queen’s head altogether. Initial ideas were produced, however in 1965 the Queen decided she wished to remain on the stamp. This led to the small profile silhouette on commemorative stamps being used instead, reminiscent of those produced in the 18th century of the English high society.

1965 Churchill Commemorative

Churchill Commemorative without the Queen’s Head 1965

A traditional silhouette portrait of the late 18th century

A traditional silhouette portrait of the late 18th century

To produce a profile portrait of the Queen, The Royal Mail approached the British sculptor Arnold Machin. He took inspiration from the simplicity of the Penny Black portrait, which was based on a medal of Queen Victoria by William Wyon. This again acknowledges the historical importance of the profile.

Arnold Machin Plaster Cast

Arnold Machin Plaster Cast

William Wyon Medal

William Wyon Medal

The image of the Queen we see today is not only practical for producing stamps but also evokes the idea of power and importance, circulating her image to the nation. The significance of the portrait on a stamp is not merely a representation of the person but as a symbol of their significance. Commemorative stamps elevate the importance of an individual by allowing them to feature prominently on the stamp, though the Queen still remains dominant as the accompanying silhouette.

Winston Churchill 1st (October 14 2014)

Winston Churchill 1st NVI (October 14 2014)

Next time you see a photograph of yourself have a think what you would look like on a postage stamp?

– Georgina Tomlinson Philatelic Assistant.

Two BPMA touring exhibitions open in Aberystwyth

Two of our touring exhibitions (Designs on Delivery and The Post Office in Pictures) are both on display at Aberystwyth Arts Centre starting tomorrow (18 January) until early March.

Designs on Delivery

Design played a crucial role in promoting social progress and technological change across Britain between 1930 and 1960. General Post Office (GPO) posters were commissioned in the context of specific channels of communication. Posters were designed for Post Office walls, pillar boxes and transport vehicles.

POST1103184

Post your letters before noon, Jan Lewitt and George Him, 1941 (POST 110/3184).

The exhibition posters offer a variety of visual language adopted to meet these different needs. GPO posters included work by those associated with both fine art and graphic design, demonstrating the blurring of the boundaries between high art and popular culture that poster design encouraged.

This exhibition showcases 25 of the best of these posters.

POST110_3177

Air Mail Routes, Edward McKnight Kauffer, 1937 (POST 110/3177) .

The Post Office in Pictures

The Post Office in Pictures is an exhibition showcasing a selection of inspiring images sourced from the BPMA’s vast collections.

Photography was one of the key tools used by the GPO PR Department (est. 1934) to reach and engage with the general public. In order to supply its fledgling Post Office Magazine with professionally-produced photographs, members of the GPO Photographic Unit began to accompany the magazine’s journalists.

Down Wapping Way, 1935 (POST 118/252).

Down Wapping Way, 1935 (POST 118/252).

The exhibition showcases 30 outstanding photographs from the 1930’s to the 1980’s. Also available to read alongside the exhibitions will be copies of the Post Office Magazines, from which many of these photographs are drawn.

The Post Office in Pictures and Designs on Delivery both open on Saturday 18 January at Aberystwyth Arts Centre and run until Saturday 8 March. Entry is free of charge and open to all.

Please let us know if you do visit the exhibitions, on dominique.gardner@postalheritage.org.uk, 0207 354 7287, or @postalheritage. We hope you enjoy your visit!

— Dominique Gardner, Exhibitions Officer

Behind the scenes; conservation in progress

Do you ever wonder what is happening to sticky tape? The answer is usually “No” and for a good reason. We all believe that it will remain nice and sticky for eternity! Especially nowadays when we have so many choices of self-adhesive tape or pressure sensitive tape with excellent qualities too; there are transparent, matte, colour, black, white, brown, red, archival ones, linen ones and so many more. The point is that we don’t think twice when it comes to applying it because we are confident about its short term effect and result. Well, I will try to change your mind a bit and show you how a well-intended attempt to stick together broken glass plate negatives turned into a painstaking nightmare.

In the mid-19th century, photographic negatives began to use glass as a support. Glass provided a sharper negative and a more detailed positive print, and soon replaced paper negatives. Like photographic prints, glass negatives are composite objects, consisting of a glass support, a binder, and an image-forming or recording substance. At the BPMA we store approximately 2500 glass plate negatives dated from 1930s to the 1950s with a variety of topics from day to day postal operations. 89 of them are damaged, with broken and/or missing parts. A common practice of preserving a broken glass plate negatives was to sandwich it between either one or two new glass plates and apply a tape around their perimeter to secure them. The quality and type of tape used varied but one thing was certain; the intention of the ‘restorer’ could only be described as a noble attempt to save what was broken.

Taped Glass Plate negatives

Taped Glass Plate negatives

Unfortunately, good intentions don’t always have the result we hoped for. So when the need arose to remove the tape, I faced a big challenge. The adhesive of the tape had permeated the emulsion layer of the glass plate negative, it had cross-linked as we say in conservation (a chemical process of bonding one polymer chain to another). This new type of bonding creates irreversible damage as it discolours and fades the image but mostly because it weakens the emulsion layer and makes it prone to flaking, putting the image at risk. Any mechanical attempt to remove it went downhill so the next idea was to use an aqueous and a chemical treatments which mean the introduction of liquid either water or solvent. I used a microscope to avoid any unnecessary contact between emulsion and water –these two things do not like each other very much.
All geared up with a microscope, a portable air extraction unit, solvent and water, apron, I have started the process of slowly moistening the tape and carefully removing it with a dentist’s spatula.

During removal. residues from adhesive stuck on surface

During removal. residues from adhesive stuck on surface

To remove tape from one glass plate negative of 80 x 100cm in dimension I have estimated it took from 14 to 20 hours. On the other hand, I have timed how long it took to apply a sticky tape on one glass plate negative mock-up of the same dimension and it took between 1-2 minutes. Pretty amazing don’t you think! Consequently in a collection of 89 damaged and taped glass plate negatives it took 3 hours to apply the tape and it would take 1780 hours to remove it, which is 254 working days! Makes you wonder why conservation sometimes can take so long!

After Removal of tape

After Removal of tape

In conclusion, I would like to emphasise to all lovely collectors out there who value and protect their collections that if you think a quick fix might solve your problem, please think twice. Besides if you are unsure about a procedure please contact a conservator who will be able to advise you and guide you to a suitable solution. In the long term, it will be a less costly and time consuming operation and it will save your precious collection for future generations to enjoy.

Before and After Conservation

Before and After Conservation

Katerina Laina ACR, MSc
Assistant Paper Conservator

Mail Rail: A Photographic Exhibition

Jonathan Bradley previews his exhibition Mail Rail: A Photographic Exhibition, which opens at the Royal Mail Archive today.

For three quarters of a century, one of the most successful underground railways in the world transported mail under the busy streets of London until its service was suspended in 2003. It remained largely unknown to the general populous aboveground.

Waiting in the dark - 1930s car in the siding. Image ©Bradley Photography, Northumberland.

Waiting in the dark – 1930s car in the siding. Image ©Bradley Photography, Northumberland.

The Post Office Railway (AKA Mail Rail) is a unique and remarkable infrastructure, being the only dedicated driverless mail haul railway in the world. It came to my attention some two years ago while surveying for another framework environment for the ongoing People : Space work. People : Space is a human spatial study and finding appropriate environments to deliver an artistic treatment to is not an easy task. However, the Mail Rail had the necessary attributes and photography began in 2011.

Descent to the Mount - Twin tunnel. Image ©Bradley Photography, Northumberland.

Descent to the Mount – Twin tunnel. Image ©Bradley Photography, Northumberland.

People : Space encourages viewers to look at spaces and areas that are or can be occupied by humans and visa-versa. Photographically capturing space is very challenging and this project often projects vistas that indirectly depict this. Frequently, the humanity element can be suggested. Within each of these pictures lies a distinct, tangible thread of humanity and though the photographs present and record a view of the railway in a quiescent state, the subtle compositional detail of the images lean the eye to regard these degrees of freedom – spaces that contained workers, movement and sound.

Relay board - 'Blue' relay board photograph. Image ©Bradley Photography, Northumberland.

Relay board – ‘Blue’ relay board photograph. Image ©Bradley Photography, Northumberland.

Consider the sound of footsteps, the noise of trains, mail being unloaded off conveyors and cherrys being clicked. Think of the people who walked the platforms, who loaded mailbags, the engineers and fitters tirelessly working in the car shed above Mount Pleasant Station, the section controllers shuffling levers and moving trains and the line crews who worked during maintenance hours who serviced the railway that is now dormant and silent. Contrast what was before with what you see today and consider these People and their Spaces.

Unable to Accept - Green and Yellow lights with acceptor panel. Image ©Bradley Photography, Northumberland.

Unable to Accept – Green and Yellow lights with acceptor panel. Image ©Bradley Photography, Northumberland.

Mail Rail: A Photographic Exhibition is on display in The Royal Mail Archive, London. Entry is free.

A selection of exclusive prints signed by Jonathan Bradley are available from the BPMA online shop.

On the map, the History Pin map

Hello, I’m Nicola and I’ve been volunteering for the BPMA since the end of January. It has been such a fantastic experience for me so I wanted to write a little blog to share what I have been working on. Interestingly, I gained my volunteer position at the archives because my cousin had put out message on twitter asking about volunteer opportunities to which Martin Devereux, our digital content manager replied, so I am as grateful to her as to Martin and everybody else at the BPMA. I have been very lucky with this volunteer placement because it has allowed me to explore my two greatest passions in life, history and photography, in an area that I had been previously unfamiliar with, that of postal history.

Postman delivering mail to a large group of hop pickers, Kent, 1935. (POST 118/467)

Postman delivering mail to a large group of hop pickers, Kent, 1935. (POST 118/467)

When I first came to volunteer at the BPMA, Martin talked to me about a few different areas that I could potentially work on but I told him I wanted to do all of them. So I have spent the past few weeks scanning, cataloguing and rehousing glass plate negatives, tagging and creating labels for online photographs, researching a couple of mysterious Victorian albums and other general archiving tasks, including working with the CALM collections database. Alongside these more recent activities, I also dedicated my first few sessions to promoting the BPMA on History Pin. This website is a photographic archive which allows organisations to share their photograph collections with the public.

Each organisation has its own channel on the website where it can upload photographs and then attach them to Google’s map to show where the photograph was taken. Each photograph or ‘pin’ can then be overlayed on top of Google Street View, allowing the public to compare the location with the original photograph. This is enhanced with the sliding tool which changes the opaqueness of the photograph on top to reveal the Google image underneath; I had great fun playing with this!

The photographs that I uploaded from the postal heritage archives depict a variety of places and people ranging from a postman delivering mail at Dover Castle to a mail van parked next to Loch Lomond in Scotland. I uploaded photographs that I thought were either visually appealing or had an interesting subject matter (or both) and had great fun searching through the archives.

Mail van by Loch Lomond. (POST 118/134)

Mail van by Loch Lomond. (POST 118/134)

As well as these singular photographs I also created three collections of photographs connected to certain subjects and events. One contained images relating to transport in postal history, another was about the opening of the Mersey tunnel in 1934 and my favourite one was about delivering mail to the hop farms in Kent. I was very pleased to hear that the first photograph from this collection was made ‘pin of the day’ a few days after I uploaded it and appeared on the Historypin homepage.

Postman delivering mail to Dover Castle. The postman, standing in front of his mail van, hands mail to a soilder. A young boy stands next to the men, pointing at the postmans mail bag. 1935. (POST 118/421)

Postman delivering mail to Dover Castle. The postman, standing in front of his mail van, hands mail to a soilder. A young boy stands next to the men, pointing at the postmans mail bag. 1935. (POST 118/421)

It has been such a great experience to volunteer at the BPMA and I have learnt so much about archiving and all the different roles in an organisation such as this. It has definitely inspired me to consider archiving, especially if related to photography in my future career.

Join the BPMA on History Pin today!

GPO Britain in pictures

The BPMA is the custodian of a photographic collection which includes about 100,000 individual photographs; the earliest is from the late 19th century and the latest ones date from the 1990s. In a previous blog on our photography collection and a talk now available as a podcast we have presented some of this fascinating material and the stories behind it, and our exhibition The Post Office in Pictures features some of the most striking images.

The GPO Britain postcard set.

The GPO Britain postcard set.

The photographs depict life in Britain at the time of the General Post Office (GPO) with its contrasts between modern urban areas and the industrial heartland, and the remote rural regions where the postman or postwoman presented a vital connection to the outside world. We have selected six of the most intriguing images for a new postcard set which is now available from the BPMA Shop.

Man posting a letter holding a cauliflower, 1949. (POST 118/1964)

Man posting a letter holding a cauliflower, 1949. (POST 118/1964)

Many of these photographs have been published in the Post Office Magazine (POST 92), which was first issued in 1934 in order to promote postal services and good relations with the public, aimed at the large postal workforce, their families and friends. The articles often presented the modernity and efficiency of the GPO’s services, such as the Post Office Savings Bank – “Everybody’s Bank” with ten million accounts, according to the author of an article in the September 1935 issue. The story on the bank, which holds “the small savings of ordinary not-very-wealthy folk in the hamlets and towns and cities of Britain”, is accompanied by several images of banking clerks entering the 120,000 daily transactions in the newly adopted accounting machines. The clerks’ efficiency in dealing with the amount of correspondence and day to day business clearly impressed the author – he dubs them ‘super clerks’.

A female clerk at the Post Office Savings Bank, on the cover of the Post Office Magazine September 1935. (POST 92)

A female clerk at the Post Office Savings Bank, on the cover of the Post Office Magazine September 1935. (POST 92)

Other sections of the magazines were regularly dedicated to news from the different UK regions. These focussed on the local postal staff and their achievements, activities and work in their local community, which, to today’s readers, provides some authentic insights into rural British communities in the 1930s and 1940s. The October 1938 Northern Ireland section, for example, features the image of a postman with a pony and trap on a rural road: “The Glenarm Bay postman goes on his delivery in a trap presented to him by local residents” (POST 118/903).

Postman with pony and trap in Northern Ireland, 1938. (POST 118/903)

Postman with pony and trap in Northern Ireland, 1938. (POST 118/903)

Other issues show postmen wading through rivers on horseback (January 1939) to reach the next village or town, or recount the peculiar history of whale bones decorating the post office exterior at Cley-next-the-Sea (March 1938).

Postman on horseback near Withypool, Somerset, 1938. (POST 118/910)

Postman on horseback near Withypool, Somerset, 1938. (POST 118/910)

Main Strain in Cley, Norfolk, 1937. (POST 118/1204)

Main Strain in Cley, Norfolk, 1937. (POST 118/1204)

The GPO Britain postcard set is now available from the BPMA Shop for £3.75.

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