Hi,
Thanks for your reply,
I am aware of the compression / resizing, it has never been a problem before.
The images that are blurry (again maybe 30-50% of them) are blurry enough that you would undoubtably notice it regardless if you've seen them before or not, if this bug is present when viewing on your device.
However, when rightclicking a blurry low res image and opening it in a new tab, it's crispy / high res. This is a bug that loads a lower than usual resolution of the images in lightboxes.
As far as I understand, squarespace creates about 6-7 different resolutions of the images we upload, and serve the appropriate resolution to us based on the amount of pixels available for each display /monitor / frame. This is what's currently bugged: it's choosing a lower resolution version than what is appropriate for some images.