Can the captures from this 25mp back make good looking prints at maybe 30 or 40 inches?
Hi Mike,
Depends on 'good looking'. Prints will look at their best in the 15x20 inch output size range, suitable for close scrutiny (reading distance).
So if you want to go to twice those dimensions, you need to use good upsampling software, and/or increase the viewing distance to twice the reading distance, say 20-25 inches distance. It also helps to use good output sharpening after the upsampling.
To put things into perspective, I've seen images covering a complete wall of exhibition booths, some 2.5 x 3 metres in size, from a single 21 MP 35mm sensor and they looked stunning. Not tack sharp, but stunningly good. Very careful upsampling and sharpening was part of the success. The added viewing distance certainly helped, but even up close, void of artifacts, it looked acceptably good.
I'm not sure if you want to enlarge a single image you already have, or whether you are in the planning phase. In the latter case, consider stitching multiple shots if your subject allows.
Cheers,
Bart