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Query about DXOMARK sharpness and real distant-resolving power (1 Viewer)

I have a somewhat geeky query about camera/lens sharpness ratings, like DXOMARK. Specifically: how might DXOMARK “sharpness” scores relate to real “distant-resolving power” of lenses of different focal lengths?

Hypothetical example:
  • Set-up 1 (50mm lens A on full-frame body X) gets a sharpness score of 40
  • Set-up 2 (300mm lens B on same body X) gets a sharpness score of 25
  • But in terms of real resolution at distance, it’s not a fair comparison, because the 300mm has already magnified by about 6x (300/50)
  • So in order to compare real resolution at distance, perhaps we should multiply the 300mm’s sharpness by 6? In other words, real resolution at distance is 40 for Set-up 1, versus 150 (=6x25) for Set-up 2
Is that broadly correct as a simple rule-of-thumb for comparing distant-resolving power of two set-ups? I imagine in reality it’s unlikely to be so straightforwardly linear, and it’s quite possible that I’m misunderstanding something basic...

[Evidently there are multiple other considerations of optics, electronics, mechanics and ergonomics that can influence real-world distant-resolving power; and image quality is not just about resolution/sharpness; and there’s also the question of financial cost; but here I’m simply looking to understand the optical test results for sharpness.]

I guess this relates to the wider question of whether sensors and processing might eventually achieve such high resolution that telephotos will become almost unnecessary??? [Though we'd presumably need to use digital zoom in the viewfinder or livescreen, to ensure we're focusing correctly on our distant object.]

Thanks to anyone who can answer this, and apologies if it’s a dumb question :)
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