I have scanned in drawings at 300 dpi and saved them as tifs. When I look at them in InDesign with the view set on "Actual Size," they look blurry. When I print out the page, they look fine. They also look fine in photoshop. What gives? I am going to export the InDesign file as a PDF and send it to an online print on demand company and I'm worried the book will come back all blurry!
Change the view quality.
View > Display Performance > High Quality Display
Because InDesign uses a proxy of your original images as you place them in InDesign. If you want to view them in Higher Quality then you have to change that.
In InDesign Click View -> Display Performance -> High Quality Display
Shortcut Ctrl + Alt + Cmd + H in Mac
Remember, you don't have to always set your display to a High Quality because the more images you will place in InDesign, you will notice that InDesign becomes sluggish.