Not showing the post image, please?

Hello,
after years of not changing anything over at janreinhardt.com I have just installed Fukasawa as a new theme.

Is there a way (editing the theme) of NOT showing the post images of my posts when viewing single posts? I DO want the post images on my front page (after all thats a main point of the theme) but I dont want it shown elsewhere, since its very large images in my case.

thanks for your help guys.