Martin Krzywinski / Canada's Michael Smith Genome Sciences Centre / mkweb.bcgsc.ca Martin Krzywinski / Canada's Michael Smith Genome Sciences Centre / mkweb.bcgsc.ca - contact me Martin Krzywinski / Canada's Michael Smith Genome Sciences Centre / mkweb.bcgsc.ca on Twitter Martin Krzywinski / Canada's Michael Smith Genome Sciences Centre / mkweb.bcgsc.ca - Lumondo Photography Martin Krzywinski / Canada's Michael Smith Genome Sciences Centre / mkweb.bcgsc.ca - Pi Art Martin Krzywinski / Canada's Michael Smith Genome Sciences Centre / mkweb.bcgsc.ca - Hilbertonians - Creatures on the Hilbert CurveMartin Krzywinski / Canada's Michael Smith Genome Sciences Centre / mkweb.bcgsc.ca - Pi Day 2020 - Piku
Embrace me, surround me as the rush comes.Motorcycledrift deeper into the soundmore quotes

optotypes: worthwhile


Martin Krzywinski / Canada's Michael Smith Genome Sciences Centre / mkweb.bcgsc.ca

2020 `\pi` day art and the piku


Fonts + Design

Snellen Optotype Font with Upper and Lowercase characters

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
SnellenMK optotype font. Uppercase, lowercase and symbols to test your eyes. (zoom)
Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
SnellenMK optotype font. Uppercase, lowercase and symbols to test your eyes. (zoom)

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.

snellen chart posters

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


Typographical posters of how the world works in the style of Snellen eye charts
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca buy artwork
A technically accurate Snellen chart using four genetic bases A T G C rendered as optotypes. The chart begins with the start codon ATG and ends in the stop codon TGA, which appears only once in the chart. Print at 16 in × 24 in. (BUY ARTWORK)

Typographical posters of how the world works in the style of Snellen eye charts
 / Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca buy artwork
A technically accurate Snellen chart using the nautical flag alphabet rendered as optotypes. Print at 16 in × 24 in. (BUY ARTWORK)

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.

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.

Snellen Optotype Letter Design

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.

lowercase

The lowercase characters should be considered experimental.

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

Download SnellenMK Optotype Font

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

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

version v7.002 11-Jul-2019

Tidied all letter forms with Fontlab 6.

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. (zoom, download SnellenMK optotype font)

version 7 — 6 Feb 2017

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

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. (zoom, download SnellenMK optotype font)

version 6 — 5 Feb 2017

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

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. (zoom, download SnellenMK optotype font)

version 5 — 4 Feb 2017

Added lowercase, digits and symbols.

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. (zoom, download SnellenMK optotype font)

version 4 — 23 Feb 2017

Adding digits.

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. (zoom)

version 3 — 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.

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. (zoom)

version 2 — 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?

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. (zoom)

version 1 — 22 Feb 2017

First attempt at lowercase characters.

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. (zoom, download font)

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news + thoughts

The Outbreak Poems

Tue 24-03-2020

I'm writing poetry daily to put my feelings into words more often during the COVID-19 outbreak.

Panic can
wait
for tomorrow.
Regrets live
on
curves not tangents.
Small chances
are
never zero.
Month's last day
waits
for another
year.

Read the poems and learn what a piku is.

Deadly Genomes: Genome Structure and Size of Harmful Bacteria and Viruses

Tue 17-03-2020

A poster full of epidemiological worry and statistics. Now updated with the genome of SARS-CoV-2 and COVID-19 case statistics as of 3 March 2020.

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Deadly Genomes: Genome Structure and Size of Harmful Bacteria and Viruses (zoom)

Bacterial and viral genomes of various diseases are drawn as paths with color encoding local GC content and curvature encoding local repeat content. Position of the genome encodes prevalence and mortality rate.

The deadly genomes collection has been updated with a posters of the genomes of SARS-CoV-2, the novel coronavirus that causes COVID-19.

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Genomes of 56 SARS-CoV-2 coronaviruses that causes COVID-19.
Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Ball of 56 SARS-CoV-2 coronaviruses that causes COVID-19.
Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
The first SARS-CoV-2 genome (MT019529) to be sequenced appears first on the poster.

Using Circos in Galaxy Australia Workshop

Wed 04-03-2020

A workshop in using the Circos Galaxy wrapper by Hiltemann and Rasche. Event organized by Australian Biocommons.

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Using Circos in Galaxy Australia workshop. (zoom)

Download workshop slides.

Galaxy wrapper training materials, Saskia Hiltemann, Helena Rasche, 2020 Visualisation with Circos (Galaxy Training Materials).

Essence of Data Visualization in Bioinformatics Webinar

Thu 20-02-2020

My webinar on fundamental concepts in data visualization and visual communication of scientific data and concepts. Event organized by Australian Biocommons.

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Essence of Data Visualization in Bioinformatics webinar. (zoom)

Download webinar slides.

Markov models — training and evaluation of hidden Markov models

Thu 20-02-2020

With one eye you are looking at the outside world, while with the other you are looking within yourself.
—Amedeo Modigliani

Following up with our Markov Chain column and Hidden Markov model column, this month we look at how Markov models are trained using the example of biased coin.

We introduce the concepts of forward and backward probabilities and explicitly show how they are calculated in the training process using the Baum-Welch algorithm. We also discuss the value of ensemble models and the use of pseudocounts for cases where rare observations are expected but not necessarily seen.

Martin Krzywinski @MKrzywinski mkweb.bcgsc.ca
Nature Methods Points of Significance column: Markov models — training and evaluation of hidden Markov models. (read)

Grewal, J., Krzywinski, M. & Altman, N. (2019) Points of significance: Markov models — training and evaluation of hidden Markov models. Nature Methods 17:121–122.

Background reading

Altman, N. & Krzywinski, M. (2019) Points of significance: Hidden Markov models. Nature Methods 16:795–796.

Altman, N. & Krzywinski, M. (2019) Points of significance: Markov Chains. Nature Methods 16:663–664.