07-15-2020, 04:03 PM
(07-15-2020, 01:08 PM)Spinifex Wrote: "Upgrade path" is an overused concept that doesn't mean as much today as it did back in 2010. Yes, it made sense back when Sony had the E-mount and they managed to (barely) fit a FF sensor in there, but now, it leads to the Nikon Z50, which is in a really poor position in the market: competing with APS-C/M43 cameras costing half as much, while costing the same as entry-level FF cameras from Sony and Canon."upgrade path" I was never interested in, I don't need to go to FF. I want a large lens selection on a small compact system. And the EF/EF-S offered this. In fact, when comparing Canon to e.g. Olympus, there was hardly any advantage of MTF over Canon in terms of weight, which counts most, provided one wants a camera with viewfinder.
What changed since 2010:
- APS-C and FF DSLR cameras had to be pretty much the same size to accommodate the mirror and prism assembly, it did not make sense to build two different mounts. Now, with mirrorless, you can have much smaller/lighter/cheaper cameras and lenses if you have a dedicated APS-C/M43 mount.
- There were very few dedicated APS-C lenses from Canon/Nikon/Sony, meaning you pretty much had to invest in FF lenses, especially if you wanted Prime lenses. So when you upgraded, you could keep the original lenses. Today, you are probably using dedicated APS-C lenses, since the difference in price size and weight with FF lenses is pretty important, so even if you upgrade to FF, you probably can't keep those lenses.
- When entry-level FF was $3000 and APS-C was $500, it made sense to invest in a system lens by lens, working up to FF. Today, it's $999 and yet still $500 for APS-C: you can just buy into FF if you want to.
tldr: it makes a lot of sense for Canon to keep EF-M (smaller, lighter, cheaper) and RF separate. Nikon is still thinking in a 2010 paradigm and it will fail them: the Z50 cannot compete with its APS-C/M43 rivals.
(07-15-2020, 09:04 AM)photonius Wrote: Well, I suspect that is the same reasoning Canon is using, i.e APS-C only on EOS-M. But the 600 and 800 mm are clearly aimed at low budget customers. Yet, the lenses were not released for EOS-M. As someone mentioned on the other thread on these lenses, they would be useful on APS-C size for maximum reach.
Just a small point. A F11 lens for an APS-C sensor with 32.5 megapixels is just really asking for trouble: you are well past the diffraction limit and buyers will be asking why the pictures are so bad. That said, I imagine we might get an equivalent DO lens for EF-M at some point. If not, maybe the rumored 100-300 mm f5.6-8 will be manageable and affordable.
- The Z50, I don't think that can be used as sample. There is no reason why one can't make a decent inexpensive body with a Z or RF mount and APS-C sensor. It was Nikon's marketing decision to make one which is too expensive.
- As to size, yes EOS-M can be made a bit smaller. But the RF mount is not that huge, the inner diameter is 54mm, the same as the old EF mount. And with the EF mount Canon was able to make the small compact SL range dSLRs that compare quite well in terms of weight with mirrorless cameras (e.g., Olympus E-M10 is only 60 g lighter than an SL2). So just imaging you take out the whole mirror box from the SL2, what you save more. So, the difference in mount diameter does not make a huge difference for body design weight differences. The reason some EOS-M and PEN cameras are small, because they strip the viewfinder, large handgrips, etc. You can do that with Z or RF as well, if you want.
As to f11, yes, I agree we are approaching diffraction. But at 24MP, f11, as the Canon APS-C tests here on OL show, the loss effect is quite minimal, not collapsing at all yet. At f16 it will start to kick in. So, to get there, you need an 60 MP on FF.