Say that a prime lens is wide enough to capture a composition but too wide to frame it exactly. Assume a zoom can frame the composition exactly.
Get in closer with the prime, et Voilà! Not always possible, of course, but in many situations it should be.
I guess I don't get the purpose of trying to establish a better/worse scenario here. Lenses are just tools. Use the one(s) most appropriate for the situation. If you're caught out lacking the best choices, make do with what you've got.
I once spent 10 days at the Grand Canyon with a nearly new camera and just one lens, a 90mm macro, 'cuz my 28–70mm didn't arrive in time for the trip (my fault for trying to buy late...local dealer was out of stock) and the 70–200mm's focusing mechanism jammed on the first day. Bad planning on my part. But I made do and actually had a great time snapping away. I also made a number of multi-shot compositions with the intent of eventually stitching 'em together. (This was in 1993...film, early days of affordable scanners, modest computing power, fairly crude editing software.) Which in due course I did.
Question: Is it possible for a downsized image from a zoom to be technically superior to the cropped image from a prime, even though optically the prime is superior to the zoom at the same focal length?
Again, is there a practical purpose behind this...like downsizing for screen display or a small-ish print?
Let's explore a hypothetical: one photo taken with an 80–400mm at the long end; and a second photo taken with a 105mm & cropped to the same field-of-view as the first photo. We're using the latest Wunderkind Kamera
, the Sony A7r, at optimal settings so as to avoid the dreaded shutter shock phenomenon.
Both photos printed at 240ppi with the cropped prime pic at full size and the zoom pic downsampled to match. I'd likely accept the cropped prime pic...it should look good. But I suspect the zoom pic will make for a nicer print, even assuming a meh
-performing lens. More sub-samples per pixel. This assumes skilled post work with each photo.
Now in the real world I'd never do this. I mean in terms of making a direct comparison. I've printed plenty of extreme crops from both primes and zooms, but they've been a better make do
kinda thing as with my Grand Canyon example above. Given the option of using a more appropriate tool, that's what I'll use.