Hi.
Short question. I use Photoshop for images. I save the image with 72dpi and for example 500 x 300 px. And when I look at the photo it’s a good quality. When I insert the photo in blocs and do a small gallery and click on a photo the quality is not the same ? Why?
thanks
tom 
Do you have WebP enabled? If so try tweaking the quality setting.
Hi, yes WepP enabled. But set it to 100. Nothing change. I try to disable …
Well, 500px is like post-stamp for high-quality Retina screens. I think you should have at least 1200px or, better, HD size of 1920px. Then you can change the quality in Photoshop (Save for the Web) and see the result before saving.
Typically, a photo saved as JPG at 50% quality and 1920px would weight around 200px. But you have to set the quality for each pic or, if they are similar, process them as batch.
Note that if you have a 4K or 5K screen, in Photoshop, you have to preview your image in save for the web at 200%.
Actually I just re read what you posted @tom2, and it’s as @svimic said above.
I think you need to make some larger images for the gallery. The smaller images are fine for thumbnails.
As above Tom - larger images are needed.
My pics on my gallery site are about 2000px on their longest side. However, slightly different from what @svimic mentioned, I export at 100% quality jpegs, but then run through ImageOptim, which generally reduces them to about 500k from 2, 3 or 4 Mb.
Also, as far as webP is concerned, I’ve had problems every time I’ve tried to use it by stuff being missing from the site (and not just pictures), so I turned it off (along with combining CSS etc) and had very few problems since.
Good luck - let’s see the site when done!
ImageOptim is a good choice.
You still have to check settings to reduce with or without loss and it actually compress your original images without preview.
Yes @svimic, the no preview or saving a copy can be a bit of a hassle, but I now duplicate my jpeg folder so I’m working on copies - well pointed out, I forgot to mention that! You get the gold star of the day for doing so!
Generally though, I find the finished reduced files better and smaller than the Photoshop/Affinity equivalents.