With the massive resolution cameras are capable of these days, clicking the 1/4 zoom setting usually results in a photo that is larger than "fit to screen".
I find culling much easier when I can view a relatively sharp 400-100px image against a clean black background.
Increasing the thumbnail size results in blurry images.
Would it be possible to create a 1-100% zoom function?
I'm going to convert this to a support ticket and have you work with John. We do support 100% zoom, so this may be either a bug or an issue with preferences.