What photo filters actually do to your image
Every filter is a stack of ordinary operations: curves, saturation scaling, colour shifts, local contrast and noise. Here is what each one does to your pixels, why...
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What image upscaling can and cannot do
Two very different technologies are sold under the same word. Interpolation enlarges an image and invents nothing; AI upscalers generate plausible detail that was...
How to shoot product photos with a phone
Your phone camera is not the problem. Window light and a bounce card, a seamless paper sweep, locked exposure and white balance, and no digital zoom will fix most...
How to scan and restore old photos
Choose your scan resolution from the output you want, not from a number someone quoted you. This covers the arithmetic, flatbed versus phone capture, dust and...
How to pull a colour palette out of an image
Palette extraction finds the colours a photo is actually made of by grouping similar pixels into clusters, which is why it gives you something usable and a plain...
How to crop a photo well
Cropping is the cheapest edit you can make and the one most likely to decide whether a photo works. What each aspect ratio is for, why the rule of thirds is a...
Why your photo is sideways and how to fix it
Your camera never rotated the picture. It wrote a note saying which way was up, and something downstream ignored it. Here is the mechanism behind sideways uploads...
How to crop a profile picture that works everywhere
Your avatar is seen at the size of a fingernail, so it has to work as a shape, not a photograph. How tight to crop, where to put the eyes, why the circular mask...
What a RAW file actually is
A RAW file is not an image. It is the sensor's unprocessed readings plus a set of instructions nobody has carried out yet. Here is what that means for bit depth...
Image licensing explained without the legalese
All rights reserved, the six Creative Commons licenses, public domain, CC0, royalty-free, rights-managed and editorial-only, explained in plain language. Plus what...
What Your Images Actually Cost on a Slow Connection
One photograph at five file sizes, measured across Slow 3G, Fast 3G and 4G. A 1.87 MB image takes 38.9 seconds on a slow connection, and a 498 KB hero already fails...
Alt Text: What Screen Readers Actually Say About Your Images
We read Chrome's accessibility tree for fourteen alt text patterns to find out exactly what gets announced. Missing alt and empty alt turn out to be opposite...