Does dpreview gallery recompress photos?
I did the test you suggested and recompression is evident, they leave unchanged the pixel size though.
Pity, because the slideshow is nice, but recompression is so strong I could notice it even with no zoom, then zooming, and even more comparing original vs full size dowload, revealed the problem.
|scrum break away by al booth|
from Sport competition
|Chinese Acrobat by lim yau tong|
|Parking Deck by Olaf R|
from Your City - Parking Garage
|Communication Tech by alberto_b|
|With & without by OBellini|
from Empty - Full