We run Narrator Version 1.3.1 on WordPress 5.2.2. We’ve encountered the issue that the header image is displayed blurry (new articles only, in this case Österreich – Tirol). All header images of past posts display correctly. And the same image displays perfectly as a normal image in the post. Do you have an idea how to solve that problem?
I found out that the post image / header image is only 1200×900, which is not retina/high res. See https://living-in-a-box.ch/oesterreich-tirol/ Previous posts which were previously published with an old theme, display correctly (full size image). How can I make new posts use the full size image?
Yes, you are right, the cover image is 1200×900. And the area where this image is being displayed is 856×642. So the number of pixels in the image is almost twice as high as the logical resolution of the area where it’s being displayed. (1200 x 900) / (856 x 642) = 1.96. This means that the appearance of theses images on Retina screens is much sharper than on regular screens.
I can see that you started showing larger images in covers, I believe 2560×1920. Please be aware that this slows down the loading time of your pages (as well as using full-sized images in the post body).
Image sizes on the web are always a compromise between quality and loading speed. I’ve found a compromise at the level of having an image that has double (1.96) the number of pixels than the logical resolution where it’s being displayed. You’ve decided to take this further. However, please be aware that this results in a certain decrease in your website’s loading speed.