Mini images size in PS 1.5.4.1

[jshop1]

Hello,

 

could somebody please help me with images size in new added products? Once I add new product, miniature imagies is getting too small.

 

Example:
My old added products are fine:
http://nakupledky.cz/7-reflektory

Detail images are big enough and it looks good:

http://nakupledky.cz/home/9-led-grow-150w-svitidlo-pro-pestovani-rostlin.html

 

Now look when I add new product the image is too small:
http://nakupledky.cz/8-mars-ii

or here http://nakupledky.cz/19-apollo

Detail of product with small images is here http://nakupledky.cz/home/55-led-grow-1600w-mars-ii-svitidlo-pro-pestovani-rostlin.html

 

All pictures I am adding has same resolution as old added pictures in old products so problem is not with resolution.

 

Could somebody please help me how to fix this problem with adding new pictures and has the same resolution?

 

Thank you