Tag Archives: stamp

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

From Vault to View: Scanning trials

It’s been an exciting month for those involved in our 3D digitisation project, as it moved into the trial stages. A while back we shared what objects we selected for the scanning. A couple of weeks ago, Mona Hess, the project’s 3D digitisation specialist, visited the BPMA to undertake trials of low-cost scanning and photogrammatery techniques. 

In conjunction with our Conservator, Krystyna Koscia, Mona tested the application of a cyclododecane spray – a substance which, when applied to objects, makes them easier to digitise with a laser–scanner.

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Cyclododecane spray applied to test objects.This substances evaporates shortly after application and makes the object easier to scan with a laser.

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Mona applies the Cyclododecane spray to test objects as Krysia looks on.

The main event of the day was the photographing of a large printing plate against a target background, from which photogrammetric measurement will be taken to create a 3D map of the plate. You can find out more about photogrammetry and other techniques we will be using in this post. The plate was also scanned using a low-cost laser scanner, to obtain a rough geometry of the plate itself. Other objects were also photographed and scanned, including a die, an embossing die, a slogan die and a roller.

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Martin examines the plate.

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Mona standing on a stool for photogrammetry imaging.

You can check out the preliminary 3D model of the plate online now, and manipulate the model. We promise that the final results will be more detailed!

Trials continue in May, when Mona will be using the laser-scanner at UCL to scan other key objects from the collection.

-Martin Devereux, Head of Digital

Rowland Hill’s Postal Reforms

If there is one man who can be said to have changed the face of the postal service forever it is Rowland Hill. Hill was a noted reformer in the Victorian era, pioneering pupil-focused mass education and working for the South Australian Colonisation Commission, but he also had an interest in the postal service. In 1837 he published and circulated the pamphlet Post Office Reform: Its Importance and Practicability. During the 1830’s there were growing calls for postal reform and Hill’s pamphlet proved influential, ultimately leading to the introduction of the world’s first postage stamp, the Penny Black, in 1840.

A cross-written letter

A cross-written letter

Prior to 1840 the postal system was expensive, confusing and seen as corrupt. Letters were paid for by the recipient rather than the sender, and were charged according to the distance the letter had travelled and the number of sheets of paper it contained. As a result cross-writing, the practice of writing in different directions, was a common method of saving paper and money, and envelopes were rarely used.

For ordinary people the cost of receiving a letter was a significant part of the weekly wage. If you lived in London and your relatives had written to you from Edinburgh you would have to pay one shilling and one pence per page – more than the average worker earned in a day. Many letters were never delivered because their recipients could not afford them, losing the Post Office a great deal of money.

But while ordinary people scrimped and saved to use the postal system, many items, such as newspapers, were not subject to charge, and Members of both the House of Commons and the House of Lords had the right to frank and receive letters for free. Well-connected individuals could thus ask their MP to frank their mail for them, further reducing Post Office revenue.

After the Napoleonic Wars postage rates were high – a sly method of taxation – and there were many other anomalies and a number of local services with different charges. The system was ripe for reform.

Rowland Hill

Rowland Hill

Rowland Hill’s solution was prepayment, and a uniform rate of one pence for all letters weighing up to one ounce. Hill made no mention of the method of prepayment but later proposed the use of stamped covers (an idea previously suggested by Charles Knight). At an official inquiry into the Post Office, Hill outlined his ideas further and suggested that “a bit of paper just large enough to bear the stamp, and covered at the back with a glutinous wash” be used. When the inquiry reported it recommended Hill’s plan to reduce postal charges and appended samples of stamped covers to the report.

The establishment of a parliamentary Select Committee chaired by fellow postal reform campaigner Robert Wallace followed, and at the same time a Mercantile Committee on postage was set up by merchants to campaign for lower postal rates. Rowland Hill was a member of the Mercantile Committee.

The Select Committee recommended Hill’s ideas in early 1839, but favoured a uniform rate of 2d. After public pressure was put on the Prime Minister, Lord Melbourne, the uniform rate was reduced to 1d, and on 15th August 1839 a bill was passed in favour of a universal penny post. The same bill abolished free franking and introduced prepayment in the form of stamped paper, stamped envelopes and labels.

Penny Black and Twopence Blue

Penny Black and Twopence Blue

Rowland Hill was appointed to the Treasury to oversee the implementation of the bill and the uniform penny post was introduced on 10th January 1840. Covers, envelopes and the world’s first adhesive stamps, the Penny Black and Twopence Blue, were introduced in May 1840. The stamps quickly proved themselves to be most popular method of prepayment.

Rowland Hill’s idea for a universal penny post was quickly vindicated. The number of chargeable letters in 1839 had been only about 76 million. By 1850 this had increased to almost 350 million and continued to grow dramatically. The Post Office’s revenue was initially cut but with the increase in the number of letters it soon recovered.

Adhesive postage stamps were gradually introduced throughout the world and with the change to charging by weight, envelopes became normal for the first time. Hill’s brother Edwin invented a prototype envelope folding machine, enabling increased production to fulfil the growing demand.

The rapid increase in the use of the postal service is also partly credited with the development of the transport system, particularly the railways, and improved opportunities for businesses in the Victorian era and beyond. The lower charges also had wide social benefits and the increasingly literate working classes took full advantage of the now affordable postal system.

Death Centenary of Rowland Hill stamp, 1979

Death Centenary of Rowland Hill stamp, 1979

Rowland Hill continued to influence the Post Office, becoming Secretary to the Postmaster General in 1846 and Secretary to the Post Office in 1854. During this period Hill established the Post Office Savings Bank, which encouraged more people to save, and introduced postcodes to London – essential in a city made up of lots of little villages all growing into each other, where streets in different parts of the city often had the same name.

Fittingly, Rowland Hill and his reforms have been celebrated on several postage stamps, including four stamps released to mark his death centenary in 1979, and the 1995 Communications stamps which commemorate the campaign for a universal penny post and the introduction of the Penny Black. Rowland Hill has also been honoured by three public statues and is buried in Westminster Abbey, a mark of how important his work was. There is also an awards scheme named after Hill for innovation, initiative and enterprise in the field of philately, and the Rowland Hill Fund, established in 1882, offers financial aid to past and present Royal Mail workers in times of need.

Pioneers of Communication: Rowland Hill stamps, 1995

Pioneers of Communication: Rowland Hill stamps, 1995

For more on postal history during the Victorian era please see our online exhibition Victorian Innovation.

Treasures of the Archive Prestige Stamp Book

Tomorrow Royal Mail releases the Treasures of the Archive Prestige Stamp Book, written by Douglas Muir the BPMA’s Curator of Philately. The book ties-in with the Postboxes Miniature Sheet also released tomorrow, and explores some of the amazing artefacts held by the BPMA.

The cover of the Treasures of the Archive Prestige Stamp Book features a sheet of Penny Blacks in our collection

The cover of the Treasures of the Archive Prestige Stamp Book features a sheet of Penny Blacks in our collection

The BPMA cares for the visual, written and physical records of over 400 years of British postal development. These records include stamps and stamp artwork, posters and photographs, documents and postal history, and objects large and small. Many of these are celebrated within the Prestige Stamp Book, including the Penny Black, Mail Coaches, the telegrams from the Titanic, the Penfold pillar box, the GPO Film Unit, stamp artwork from the era of King Edward VIII, and GPO posters.

The Prestige Stamp Book is lavishly illustrated with images of items from the BPMA collection and contains four exclusive stamp panes unavailable anywhere else, including all four of the Postboxes stamps.

The Postboxes stamps celebrates the many types of wall box which provided a cheaper and more practical alternative to large pillar boxes in less populated or remote areas. From 1857 wall boxes began appearing in walls, buildings or brick pillars and were later to be found on poles and lamp posts.

Production of wall boxes ended in 1980, and in 1995 freestanding pedestal boxes were introduced, but around 114,000 post boxes of all kinds still exist across the UK.

Four iconic wall mounted boxes appear on the Miniature Sheet and within the Prestige Stamp Book:

1st Class – George V Type B Wall Box

This example with the royal cipher of George V was cast by W T Allen & Co Ltd, London, between 1933 and 1936, and is from Cookham Rise near Maidenhead.

56p – Edward VII Ludlow Box

Introduced in 1887 this type of standardized box derives its name from the foundry where many of them were made. This example is from Bodiam, East Sussex.

81p – Victorian Lamp Box

The lamp box could also be attached to lamp post or other such structure. This example is from Hythe in Kent and was installed in 1896.

90p – Elizabeth II Type A Wall Box

This Elizabeth II Wall box is located in Slaithwaite near Huddersfield and would have been made between 1962 and 1963.

Postboxes stamp pane from the Treasures of the Archive Prestige Stamp Book

Postboxes stamp pane from the Treasures of the Archive Prestige Stamp Book

Other products available as part of the Postboxes stamp issue are a Presentation Pack, First Day Cover Envelope, Stamp Cards, Press Sheet, Generic Sheet, and special First Day Covers cancelled and stamped from Tallents House.

For further information on these releases please see the Royal Mail Stamps & Collecting website. Details of some of the letter boxes held by the BPMA can be found in the Collections section of our website.

The United States on British stamps

Tomorrow citizens of the United States will celebrate Independence Day, marking the approval by Congress of the Declaration of Independence in 1776. As Britain was the country from which the United States became independent, you may think that this date has never been celebrated on a British stamp, but in fact it has.

The Bicentennial of American Independence stamp (1976)

The Bicentennial of American Independence stamp (1976)

A stamp released on 2nd June 1976 to celebrate the US Bicentenary shows Benjamin Franklin, one of the Committee of Five who drafted the Declaration of Independence, and the first Postmaster of the United States. Franklin was also the subject of the first US postage stamp, released on 1st July 1847.

Three further stamps with American themes were released by Royal Mail in the 1990s. In 1992, 42 member countries of CEPT (Conference of European Postal & Telecommunications), including the United Kingdom, released stamps on the theme of Voyages of Discovery in America. The first UK stamp shows Christopher Columbus’ ship, the Santa Maria, about to make landfall in the Americas. The second UK stamp shows the Kaisei, a Japanese brigantine which was involved in the Grand Regatta Columbus, an event celebrating the 500th anniversary of Columbus’ journey. Participating in the rally were members of Raleigh International, which has organised charitable expeditions since 1978.

The Landfall in the Americas and Grand Regatta Columbus stamps (1992)

The Landfall in the Americas and Grand Regatta Columbus stamps (1992)

The Settlers Tale: 17th Century Migration to the Americas (1999)

The Settlers' Tale: 17th Century Migration to the Americas (1999)

In 1999 Royal Mail celebrated the approaching Millenium by releasing a number of sets of stamps on various themes. The Settler’s Tale stamps, on the theme of migration to, from and within the UK, were released on 6 April 1999 and include a stamp on migration to the Americas in the 17th Century. The stamp shows a Pilgrim couple trading with a Native American.

But perhaps the most interesting depictions of the Americas on British postal stationery are the envelope and letter sheet designed by William Mulready. The Mulready stationery was released at the same time as the Penny Black, but proved unpopular, partly due to the elaborate design. The design shows Britannia between depictions of the continents of Asia and America, and, in the lower corners, small family groups anxiously reading letters. The Americas are represented by Pilgrims, Native Americans, and toiling slaves – remember, this was 1840! (For a closer view of the Mulready stationery see Volume II of the R M Phillips Collection, an award-winning collection of British stamps from the Victorian era in the care of the BPMA.)

A coloured version of The Mulready Envelope (1840)

A coloured version of The Mulready Envelope (1840)

So, Happy Independence Day to our readers in the United States, and if you’d like to tell us about US stamps with British themes please leave a comment.