Hi @TravellerG ,
This is a very interesting post!
Unfortunately, I’m not able to do this test myself right now, but I’m enjoying the photos and results you’ve shared.
The main difference I notice between the three photos of various JPEG quality, is the saturation of the colours and the sharpness of the lines. But I’ll wait for your next post to find out your explanation! 
It’s fine, dear @DeniGu ,
when time permits, practice a little, so that these techniques will be handy, when needed. I know that there are umpteen tutorials, which usually will not understandable to many - I am trying to make points simple, straight and clear - I hope so.
Hope you could see the DPI & PPI Post - If I mention a POST in a reply, will it be treated as a harassment? - just for my academic knowledge - sorry, if I am troubling you.
Also, when you feel, you can directly ask me not to tag you - but God willingly, let it not happen.
Thanks
Hey @TravellerG ,
You do manage to make your point understandable, and I’m sure this is much appreciated by other Local Guides, too.
Mentioning your posts is not considered harassment, and I’d love to check out your new article!
Please feel free to tag me in your posts, as I enjoy reading them.