Did you turn on high quality preview in the context menu when clicking with the right mouse button on an image?
Is the actual resolution still 300 ppi (not dpi)? Have a look into the link panel. If they are scaled in InDesign, the resolution will change too. (Are they scaled in InDesign?)
300 ppi is good enough for the most puposes.
Thanks for replying. Another forum member just mentioned turning on high quality display which has made a huge difference, the simplest of things! The res is in ppi in Indesign. I also hadn't discovered the links panel, but will always have it open now!
Thanks for your help.
No need to have it open now. You can open once your Preflight Panel, define and select a profile which will warn you, when your document has specified problems (like a resolution lower than a specified value, missing font, format overrides, etc.). Then you can close it and will show up at the bottom of your window, when problemes are detected.
I've no idea what a preflight panel or how to select a profile but I will find out!
Menu Bar > Window > Output > Preflight
Bottom of the document window, where the (No) Error indicator is, you can click on it and select open Preflight Panel.