You export a sharp photo, upload it, and the version on the network is softer, flatter or oddly coloured. It is not a bug and it is not your phone. Every network re-encodes every image to save space, and what you can control is how well your file survives it.
What happens to it
- It is resized. If your file is larger than the network displays, the network scales it down by its own method, which is rarely the best one.
- It is compressed again. A photo that was already compressed once — a screenshot, an image forwarded through a messenger — loses a little more each time.
- Its colours are interpreted. A file in an unusual colour profile can look dull or shifted when the network assumes a standard one.
What to send
- 1Export from the original, not from a copy that has been through a messenger or a screenshot.
- 2Use the sRGB colour profile. It is what browsers and phones expect, and it is the least likely to shift.
- 3Make the long side roughly the size the network shows. The exact figure depends on the network — the requirements article lists them — but between about 1080 and 2000 pixels suits most feeds. Larger does not help, and a very large file can be scaled down badly.
- 4Save as a high-quality JPEG: near the top of the quality scale, not at the maximum. Keep the file under a few megabytes.
- 5If you sharpen, do it after resizing, and lightly.
What not to do
- Do not upscale a small image to make it bigger. The network will compress the blur.
- Do not upload a screenshot of your photo.
- Do not judge the result by a thumbnail on your desktop. Check on a phone, at the size people will actually see.
Text is the first casualty
Small text and thin lines are the first things compression damages. If a graphic has words in it, make them larger and heavier than looks necessary on your screen.
You will never get back to the original. You can get close enough that nobody notices, which is the real goal.