After some research found how to stop wordpress from making 3 or 4 image sizes on upload but still get (I think) Atahualpa making 2 smaller image sizes 150 and 400, where would I find the settings for this?

I'm using the latest versions of everything.
Thanks in advance.

you will have to do two things
1) go to ATO->Post THUMBNAILS and set both 'Post Thumbnail Width' and 'Post Thumbnail Height' to zero
2) edit functions.php and change line 689 (version 3.7.20) from

	add_image_size( 'single-post-thumbnail', 400, 9999 ); // Permalink thumbnail size

tp

//	add_image_size( 'single-post-thumbnail', 400, 9999 ); // Permalink thumbnail size

you will have to make this change to function.php after each upgrade.

NOTE: if you use a featured image in your post and display it as an excerpt, you will get the full size image displayed.

after doing this I also found woocommerce.php has exactly the same thing so doing the same there totally fixes the woocommerce blurry-fuzzy pictures problem.

Thanks Juggledad for continuing my learning process