Bad Image Quality in Gallery Post Thumb

Hi and all the best to you all for 2015!

In gallery post the image quality in thumb preview is something "bad". http://www.gavick.com/demo/wordpress/steakhouse/?cat=15

Any idea?

kind regards Joerg

Update: if i klick on "next" or "back" ill be navigating trough all images .. not only from the related post. From my point of understanding only images should be displayed from the related gallery .. http://asados.at/?attachment_id=1461

Hello,
Thank you and the same wishes for you!

Regarding the issue, thanks I've changed this gallery to 4-column layout, it's default wordpress gallery, so you can use more columns or change the image size (i.e. from thumbnail to medium), you have to edit this gallery post and edit gallery.

Update: Not all images are displayed - only images which are attached to the same post/page.