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Fonts + Design

Snellen Optotype Font with Upper and Lowercase characters

In the process of designing my Snellen Eye Chart typographical posters, I came across the Snellen font by Andrew Howlett. I wasn't happy with all the letters, so I made attempts at giving the font an update. I call this redesign "Snellen MK", to avoid conflict with Howlett's "Snellen".

Not being a font designer, I will likely get myself into trouble.

1 · Snellen chart posters

While making my Snellen chart series, I entered the rabbit hole of optotype fonts ... and I can't get out!

The charts don't necessarily use the latest version of my Snellen font design, which fluctuates as my mood about some of the letters changes.

2 · Optotype fonts

The optotype requirement is that letters be designed on a 5 × 5 grid, and have constant stroke width. This means that both lower and upper case letters need to share the grid and stroke. To stay compatible with the eyechart paradigm, letters should be as obvious as possible.

Lorrie Frear's article What are Optotypes? Eye Charts in Focus is a great read about optotypes and eye charts.

3 · Snellen Optotype font design

3.1 · Uppercase

The uppercase letter design uses Herman Snellen's original chart as inspiration.

I have modified the design by Andrew Howlett (see below) for some letters. All the changes are relatively minor: more serifs and consistent stroke width for bars on R and K.

3.2 · Lowercase

The lowercase characters should be considered experimental.

The progress of my redesign is shown below. I would greatly appreciate feedback and suggestions!

4 · Download SnellenMK (v7.002 11-Jul-2019)

The distribution contains both Andrew's version and my redesign.

v7.002 11-Jul-2019 — Download SnellenMK optotype font

5 · Change history

5.1 · v7.002 11 July 2019

Tidied all letter forms with Fontlab 6.

Snellen Optotype Font / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Snellen optotype font (version v7.002 11-Jul-2019) that includes both upper and lower case characters, along with most punctuation and some symbols. Based on design by Andrew Howlett.

5.2 · v7.000 6 Mar 2017

Fixed g and e. Thanks to Makeesha Fisher for suggestions.

Snellen Optotype Font / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Snellen optotype font (mk.v.7). Original design by Andrew Howlett (left) and my redesign (right), which includes both upper and lowercase letters as well as digits and symbols.

5.3 · v6.000 5 Mar 2017

Adjusted serifs on f, j, l, o, t to extend the full width of the grid. Added a lot more symbols.

Snellen Optotype Font / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Snellen optotype font (mk.v.6). Original design by Andrew Howlett (left) and my redesign (right), which includes both upper and lowercase letters as well as digits and symbols.

5.4 · v5.000 4 Mar 2017

Added lowercase, digits and symbols.

Snellen Optotype Font / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Snellen optotype font (mk.v.5). Original design by Andrew Howlett (left) and my redesign (right), which includes both upper and lowercase letters as well as digits and symbols.

5.5 · v4.000 23 Feb 2017

Adding digits.

Snellen Optotype Font / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
SnellenMK optotype font (mk.v.4). Original design by Andrew Howlett (left) and my redesign (right), which includes both upper and lowercase letters as well as digits.

5.6 · v3.000 22 Feb 2017

I'm exploring the lowercase characters. I don't know what I want to do with them. Make this into a more standard font in which lowercase letters are smaller, so that letters can fit their roles clearly when text is set in sentence case, or fill out the full optotype grid.

Snellen Optotype Font / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
SnellenMK optotype font (mk.v.3). Original design by Andrew Howlett (left) and my redesign (right), which includes both upper and lowercase letters.

5.7 · v2.000 22 Feb 2017

Flushed out some inconsistencies in the uppercase characters. Added serifs to more letters.

Now all the letters occuppy the full 5 × 5 grid, including the I, whose serifs were widened to allow this. While this new uppercase I isn't as pretty as the old one, it makes the entire typeface more consistent to its optotype roots.

Still struggling with the G. In the original version, the descending stroke was cut off in the middle of a grid, which I didn't like.

The S has been fixed—thanks to Elanor Lutz for feedback.

I've color coded the characters slightly differently, drawing attention to ones that I feel need more thought.

The lowercase characters aren't color coded (yet) because ... most of them need help. Primarily, I'm vacillating between making them fill the full size of the 5 × 5 square, just like the uppercase characters, and keeping them confined to a 4 × 4 square, which incurs loss of legibility. If I make the letters the same size, it will be impossible to distinguish lowercase and uppercase characters some cases (e.g. c, i). Perhaps this is desired?

Snellen Optotype Font / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
SnellenMK optotype font (mk.v.2). Original design by Andrew Howlett (left) and my redesign (right), which includes both upper and lowercase letters.

5.8 · v1.000 22 Feb 2017

First attempt at lowercase characters.

Snellen Optotype Font / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
SnellenMK optotype font (mk.v.1). Original design by Andrew Howlett (left) and my redesign (right), which includes both upper and lowercase letters.
news + thoughts

How Analyzing Cosmic Nothing Might Explain Everything

Thu 18-01-2024

Huge empty areas of the universe called voids could help solve the greatest mysteries in the cosmos.

My graphic accompanying How Analyzing Cosmic Nothing Might Explain Everything in the January 2024 issue of Scientific American depicts the entire Universe in a two-page spread — full of nothing.

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
How Analyzing Cosmic Nothing Might Explain Everything. Text by Michael Lemonick (editor), art direction by Jen Christiansen (Senior Graphics Editor), source: SDSS

The graphic uses the latest data from SDSS 12 and is an update to my Superclusters and Voids poster.

Michael Lemonick (editor) explains on the graphic:

“Regions of relatively empty space called cosmic voids are everywhere in the universe, and scientists believe studying their size, shape and spread across the cosmos could help them understand dark matter, dark energy and other big mysteries.

To use voids in this way, astronomers must map these regions in detail—a project that is just beginning.

Shown here are voids discovered by the Sloan Digital Sky Survey (SDSS), along with a selection of 16 previously named voids. Scientists expect voids to be evenly distributed throughout space—the lack of voids in some regions on the globe simply reflects SDSS’s sky coverage.”

voids

Sofia Contarini, Alice Pisani, Nico Hamaus, Federico Marulli Lauro Moscardini & Marco Baldi (2023) Cosmological Constraints from the BOSS DR12 Void Size Function Astrophysical Journal 953:46.

Nico Hamaus, Alice Pisani, Jin-Ah Choi, Guilhem Lavaux, Benjamin D. Wandelt & Jochen Weller (2020) Journal of Cosmology and Astroparticle Physics 2020:023.

Sloan Digital Sky Survey Data Release 12

constellation figures

Alan MacRobert (Sky & Telescope), Paulina Rowicka/Martin Krzywinski (revisions & Microscopium)

stars

Hoffleit & Warren Jr. (1991) The Bright Star Catalog, 5th Revised Edition (Preliminary Version).

cosmology

H0 = 67.4 km/(Mpc·s), Ωm = 0.315, Ωv = 0.685. Planck collaboration Planck 2018 results. VI. Cosmological parameters (2018).

Error in predictor variables

Tue 02-01-2024

It is the mark of an educated mind to rest satisfied with the degree of precision that the nature of the subject admits and not to seek exactness where only an approximation is possible. —Aristotle

In regression, the predictors are (typically) assumed to have known values that are measured without error.

Practically, however, predictors are often measured with error. This has a profound (but predictable) effect on the estimates of relationships among variables – the so-called “error in variables” problem.

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Nature Methods Points of Significance column: Error in predictor variables. (read)

Error in measuring the predictors is often ignored. In this column, we discuss when ignoring this error is harmless and when it can lead to large bias that can leads us to miss important effects.

Altman, N. & Krzywinski, M. (2024) Points of significance: Error in predictor variables. Nat. Methods 20.

Background reading

Altman, N. & Krzywinski, M. (2015) Points of significance: Simple linear regression. Nat. Methods 12:999–1000.

Lever, J., Krzywinski, M. & Altman, N. (2016) Points of significance: Logistic regression. Nat. Methods 13:541–542 (2016).

Das, K., Krzywinski, M. & Altman, N. (2019) Points of significance: Quantile regression. Nat. Methods 16:451–452.

Convolutional neural networks

Tue 02-01-2024

Nature uses only the longest threads to weave her patterns, so that each small piece of her fabric reveals the organization of the entire tapestry. – Richard Feynman

Following up on our Neural network primer column, this month we explore a different kind of network architecture: a convolutional network.

The convolutional network replaces the hidden layer of a fully connected network (FCN) with one or more filters (a kind of neuron that looks at the input within a narrow window).

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Nature Methods Points of Significance column: Convolutional neural networks. (read)

Even through convolutional networks have far fewer neurons that an FCN, they can perform substantially better for certain kinds of problems, such as sequence motif detection.

Derry, A., Krzywinski, M & Altman, N. (2023) Points of significance: Convolutional neural networks. Nature Methods 20:1269–1270.

Background reading

Derry, A., Krzywinski, M. & Altman, N. (2023) Points of significance: Neural network primer. Nature Methods 20:165–167.

Lever, J., Krzywinski, M. & Altman, N. (2016) Points of significance: Logistic regression. Nature Methods 13:541–542.

Neural network primer

Tue 10-01-2023

Nature is often hidden, sometimes overcome, seldom extinguished. —Francis Bacon

In the first of a series of columns about neural networks, we introduce them with an intuitive approach that draws from our discussion about logistic regression.

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Nature Methods Points of Significance column: Neural network primer. (read)

Simple neural networks are just a chain of linear regressions. And, although neural network models can get very complicated, their essence can be understood in terms of relatively basic principles.

We show how neural network components (neurons) can be arranged in the network and discuss the ideas of hidden layers. Using a simple data set we show how even a 3-neuron neural network can already model relatively complicated data patterns.

Derry, A., Krzywinski, M & Altman, N. (2023) Points of significance: Neural network primer. Nature Methods 20:165–167.

Background reading

Lever, J., Krzywinski, M. & Altman, N. (2016) Points of significance: Logistic regression. Nature Methods 13:541–542.

Cell Genomics cover

Mon 16-01-2023

Our cover on the 11 January 2023 Cell Genomics issue depicts the process of determining the parent-of-origin using differential methylation of alleles at imprinted regions (iDMRs) is imagined as a circuit.

Designed in collaboration with with Carlos Urzua.

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Our Cell Genomics cover depicts parent-of-origin assignment as a circuit (volume 3, issue 1, 11 January 2023). (more)

Akbari, V. et al. Parent-of-origin detection and chromosome-scale haplotyping using long-read DNA methylation sequencing and Strand-seq (2023) Cell Genomics 3(1).

Browse my gallery of cover designs.

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
A catalogue of my journal and magazine cover designs. (more)

Science Advances cover

Thu 05-01-2023

My cover design on the 6 January 2023 Science Advances issue depicts DNA sequencing read translation in high-dimensional space. The image showss 672 bases of sequencing barcodes generated by three different single-cell RNA sequencing platforms were encoded as oriented triangles on the faces of three 7-dimensional cubes.

More details about the design.

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
My Science Advances cover that encodes sequence onto hypercubes (volume 9, issue 1, 6 January 2023). (more)

Kijima, Y. et al. A universal sequencing read interpreter (2023) Science Advances 9.

Browse my gallery of cover designs.

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
A catalogue of my journal and magazine cover designs. (more)
Martin Krzywinski | contact | Canada's Michael Smith Genome Sciences CentreBC Cancer Research CenterBC CancerPHSA
Google whack “vicissitudinal corporealization”
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