PDFs are not rendering well!

pdf-tools version 1.1.0 release changed the default value of pdf-view-use-scaling to t (previously, it was nil). This has been done keeping in mind that most modern monitors are HiDPI screens, so the default configuration should cater to this user. If you are not using a HiDPI screen, you might have to change this value to nil in your configuration

(setq pdf-view-use-scaling nil)

to scale the images correctly when rendering them.