Yes, that's true, but the difference is not as great as some seem to think. Here's a shot I took to compare the 50mp 5DS with the 26mp RP. These scene was shot using a Tamron 85mm f/1.8 VC at f/5.6, and is apparently one of my highest resolving lenses, nearly matching Otus levels at this aperture in the centre. Studio tripod, delayed release etc etc. Here's the whole frame:
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At 300 dpi the native output of the 5DS is 29" across long side. So I printed the middle of this image onto A4. The RP has a native output size of 21" long side at 300 dpi. To produce matching print sizes I upscaled the RP image to 29" across at 300 dpi. This was only done in PS, not with any fancy upsizing software.
Here is a photo of the two prints. Remember that the full size image is 29" across; this is just the middle for a comparison. Now it should be immediately obvious which was shot on the 50mp 5DS and the budget 26mp RP. Can you tell which is which ? Sure, the 50 mp is better when you press your nose up to the print. I apologise for the difference in contrast but I'm not doing it again !
Incidentaly the wire mesh on that cage is 3mm and the distance is 300m, yet some people call 24 mp "low resolution".
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