Best way to animate image with grow effect

Animating an image with Grow can create a blurry image if you grow it too much.  I'd like to create the image so it appears (fades in) at 33% size then grows to 100% size, leaving a crisp-clear image.  Sizing the image to 33% in PowerPoint results in a pixeled imaged when grown to its normal 100% size.

It seems to be difficult to leave the image at 100% then fade in at 33% then grow to 100%.  I've had all kinds of unpredictable results, e.g., it grows to 300%.  Every permutation I've tried has been another difficulty.

So without enumerating all the issues, is there a good workable way to do this that I am missing out on?