The Library of Congress recommends 300 DPI for the archival of important documents. That means pictures like V-J Day in Times Square, Tank Man and John Von Neumann’s original manuscripts. It’s silly that I scan at 64x higher resolution!

I own a Epson Perfection V550, capable of a sampling/effective resolution at 2400 DPI. I scan all media at 2400 DPI, including my roll up and atlas map collection. Each scan is approximately Letter sized, takes 10 minutes and occupies 40mb. Scans are taken of the surface, with a laptop on top to press the media close to the glass, and the media is moved for each such that there is around an overlap of 2 inches on each edge. The resulting set of scans is stitched and blended using the Image Composite Editor which, despite its age, has great output. Each map usually takes multiple hours at the least, some take days to weeks.

Most of my maps are at minimum 10 gigapixels, exceeding the largest composite picture ever taken by the Hubble Space Telescope. My current largest, which is 80 by 70 inches or 6.6 by 5.8 feet, is 31 gigapixels. It would have competed for the award of largest photograph ever in April 2010, if a photograph taken less than a millimeter away counted!

Each map takes from a day to a week to scan entirely. Please enjoy some very high resolution maps!

link How I Got Them

As mentioned in my Study Abroad blogpost I obtained my first 3 maps in Utrecht when I studied abroad. I was made aware of a school card seller through a small sign on a usually locked storefront, Burgemeester Reigerstraat 47 and adjacent buildings. It read:

Old school cards, a nice gift!
Info: 06-52.67.35.90
Open: Saturdays 1:00 PM - 5:00 PM

Not the most enticing advertisement. The strict open schedule meant that I could only visit when I was not actively traveling that weekend (a rare thing). I also was not sure what a school card was besides what I could see through the window.

This was my introduction to collecting maps. At the time I was not even sure what I was looking for, but I’ve always been interested in visualizations and artistic depictions of data so I was convinced to visit. The rest is succinctly described by my blogpost:

On my first visit I discovered that "school card" is a specific type of hangable poster,
most commonly used for maps, and that school cards made before the 1980s were commonly paper on fabric.
This style of map is not only durable and valuable but cheap and beautiful.
An amazing combo for a map nerd on a budget.
It became my weekly haunt if I were not traveling that day, which was not often.

This taste in roll up maps has led me to specialty map stores in the US, as most map stores only sell atlas maps, books or reprints. Roll up maps, especially from the 70s or before, are rarities even in this business. I have managed to find various stores that sell roll up maps if I go by appointment.

It’s now a joke among my friends just how many maps I have in my apartment. They liken it to an explorer’s study like one that Indiana Jones would sit in and smoke a cigar. I’m still working on making it look that good. I like to call it the museum, since I like to engage with them as if they were historical artifacts worth studying on their own merit. It’s enjoyable to gaze at them and observe how places have changed since the 50+ years since these maps were created in Chicago, Zeist, Groningen, Moscow or Tokyo.

link How I Display Them

I display and package my maps through the DeepZoom standard. The Image Composite Editor can natively export a nested directory in the correct format, but as there are easily hundreds of thousands of files in each DeepZoom image it takes a prohibitively large amount of physical space to store the images as is, as well as having a significant performance impact. This is due to the physical disk sector size, which is 4KiB on modern drives. As each file is only 256x256 pixels and average 4.5KiB at the lowest zoom the physical size of the files on disk is actually usually twice what they actually are, in order to pad to a multiple of the disk sector size.

My approach is storing the files in a ZIP archive. ZIP allows for random access of files within, as they are compressed individually, but with all files being packed together as there is no requirement for files to pad to a multiple. ZIP archives allow for the full storage of 200000x200000 pixels while allowing for the instantaneous loading of the image at a lower resolution, all in one easily distributable file.

link The Collection (So Far)

link Europa bodemgebruik bij waar mensen wonen (Europe land use where people live) 1980

Published by Dijkstra’s publishing house in Zeist in 1980. It’s printed on linen and measures 205cm by 185cm.

link Die Welt im 17. und 18. Jahrhundert (The world in the 17th and 18th centuries) 1966

Designed by Georg Westermann Verlag in 1966 and produced by Denoyer-Geppert Co of Chicago. It’s printed on linen and measures 225cm by 140cm.

link Bos-Zeeman Utrecht 1962

Offset printed in Dingen (Groningen NL) by the publisher Noordhoff in 1962. It’s printed on linen and measures 43cm by 35cm.

link 新町名番地入最新大東京全圖 (Latest Map of Greater Tokyo) 1934

Designed by Yoshio Mori and printed by Seiji Iguchi for 40 sen (0.4 yen) in 1939 (this is an updated version of the 1934 original). That means this map cost 11 cents in 1939, or 2.05$ in 2020. I paid 4000 yen for it so it received a 40,000x markup! It was initially designed for an atlas and measures 43cm by 31cm. Some other old atlas maps of Japan can be found here.