... I would personally agree that the gap btwn 45 and 60mp is too tiny to be noticeable, but many seem to disagree.
I have both models and can see a difference at 100% magnification, but it's really small.
I my view, what makes the largest difference in actual print sharpness, if any is needed (e.g., for enlargement of just a part of the frame), is the use of Topaz's AI Gigapixel software. It takes a bit of learning to use the software to best advantage (for example, cut back - like in half - the default sharpening in the PS raw converter to eliminate halos), but it's a piece of software that I think is worth the price.
Paul
www.PaulRoark.com
