Comparing the same photo I have on flickr.com and on my own website - somehow the resize works much better, on the medium sizes in flickr as to when it looks very blurry and in low quality on my own page.

the thumbnails are satisfactory - but the bigger image (on image.php) is not at all nice

I have compression set to 99%

mo

compare http://pictor.us/canvas/cache/flavored/alunara.jpg_595.jpg
to http://flickr.com/photos/sorrenta/549055313/

big difference right?

and the original uploaded image is bigger than the one you see there.. so its not a enlarged one.

Yes, I noticed it too a while ago.
http://www.zenphoto.org/support/topic.php?id=647&replies=4
Unfortunately, there wasn't any solution for this problem...

I believe the Flickr sharpens the images using unsharp mask or similiar function so the photo looks more vivid and sharper

Looks like unsharp mask to me. Zenphoto does have this built in as an option for thumbnails, but it's processing hit is a bit too much for the larger images. You can enable it if you like in i.php by hacking the conditional statement a bit...

@ bigjimmy @ trisweb - thanks !!!

hmmm, yes something to consider !
between image quality and a server crash (?)

I chose to upload my photos in the final size they will be displayed and calling the original image in the theme thus bypassing any need for a large image to be created and called.

and I might just enable sharpening for larger images also seeing how they will be cached for later and the process has to only take place once.

))

thanks for the information :]

How do I enable it for photos (not thumbs)? What needs to be changed/added in i.php? Thanks in advance!