(solved) How do you change what image size (i.e. medium image) a category is linked to- beyond image preference in BO

[carla]

Hi
I am sorry if this has been posted, I just couldn't find. Can someone please point me in the right direction on how to change the code for certain category image sizes (beyond the image preference screen in the back office) as far as what preference it directs the image to size to.

For example my code has the subcategory image and the thumbnail image apparently both linked to the medium image preference size. I wanted my subcategory pictures bigger so changed the medium preference size from 80 x 80 to 150 x 150 and refreshed the medium category image but now my thumbnails under my products are too big. I would like to single out one or the other and change it so that they are not the same size. I do not know where in the code it is specified for these categories to link to "medium image".
Although my site is in creation and still not presentable here is the link

I am a beginner so if you mention code to me, will you please tell me what directory you are in so I can be sure to find it, for some reason I notice even when I use firefox etc- the line numbers never match up to the lines in the code.

I would be so grateful for anyone's help. I am sure this is very simple to most