I’ve been participating in the 30-chart study challenge initiated by Zan Armstrong in the Elevate data viz community Slack. I’m only 60% through, but have already enjoyed the practice of analyzing specific design details and why they were effective. It’s also been helpful for adding charts growing weary of the purgatory that is my bookmarks folder into my personal data viz database.

One of these challenge posts became a roundup of charts using a “zoom-in” as a design solution. Given the 90-day limit of Slack messages, I shall save this chart collection here for future reference.

The chart that started the thread

This 2020 election cartogram, designed by Anna Wiederkehr, shows which candidate had the lead in vote count by state and point in time. The “zoom-in” circles on Georgia and North Carolina are ✨chef’s kiss.✨ From the layout to the added support of the annotations to the subtle, satisfying change in the arrow color, the zoom-in is a great design solution for showing where and when the lead changed.

Other “zoom-in” charts

Side note: Does anyone know the term for this design solution? Else, I shall continue using the very technical nomenclature of “zoom-in.” In more interactive contexts, I believe the terms “zoom and pan” or “brushing” are used, but we move.

This WaPo chart from Hannah Dormido (h/t a LinkedIn post from Jon Schwabish) shows the changes in the S&P in relation to a specific event referenced in the story. Showing these changes required having a tightly-framed vertical axis, so adding a mini-chart to reference the zero baseline created a nice balance in understanding scale.

This Axios chart from Sara Wise similarly highlights part of a zoomed-out line chart, though for a different purpose. In this story, the mini-chart allows the reader to see historical context while the main line chart zooms-in on an acquisition’s effect on the market.

This brilliant Bloomberg Graphics chart from Marie Patino uses interactivity to zoom-in on individual metro areas amid a logarithmic scale. The transparency and white outlines of the semicircles, the clearly-labeled hover state, and the tangible movement in the axis supplement the zoom-in’s effectiveness.

Another Bloomberg Graphics chart using zoom-in! Elena Mejía uses zoom-in here to highlight very small state margins (and thus one of the main takeaways of the chart/story)! I like the texture the dashed outlines for the zoom-in, zoom-out circles add to the overall chart while visually differentiating them from the chart baseline.

And finally, one of my own attempts at using a zoom-in. I highlighted parts of a line chart to “zoom-in” on particularly exciting moments in the chess game, showing just how close the players were to zero seconds left.

While “zoom-ins” are not particularly revolutionary—the inset map is, after all, a staple in maps, collecting examples of them in charts is helpful for seeing different data viz designers’ approaches. From rectangular outlines to gray highlights to connecting arrows, creating this roundup has reminded me of possibilities to add to the toolkit.

Do you have an example of a “zoom-in” chart? Do you know the name of this design solution and wish to save me from a future of typed hyphens and quotation marks? Please reach out < 3!