...
a jpg
600x600 density (we aren’t totally sure why this matters, but think it’s what we’ve been doing)
progressive JPG (displays better while in process of being loaded by browser)
700 pixels wide x 700 pixels tall (we have a 350pixel spot on the page, and want double density to look good on high-res displays)
with a name ending in
_2x.jpg, consistent with the other files in the featured topics asset directory.
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