Originally posted by kenspo There is a difference between Ziess primes and what I'm talking about. But if you prefer to use the FF with a crappy kitlens, go ahead.
I wasn't talking about the kit lens, more like inexpensive but good primes and zooms, but in some cases even a kit lens will resolve more on more MP or larger format (or both) than a super-good lens on lesser MP or smaller format.
Quote: I ment, that its no point buying the best camera house if you dont have the glass to use on it. That is not a myth.
What is a myth is that you need 'the best glass', or you won't see any benefit to more MP, or FF, or both. This gets repeated all the time because it sounds 'truthy' and it has it's genesis in the film days, where it was a bit more true.
In the example given here, the Tamron 70-200 2.8 vs, the upcoming Pentax 70-200 2.8 (or existing Nikon/Canon 70-200 2.8 VR II,) the inference people make is that you should dump the Tamron and get the Pentax/Nikon 70-200 in order to 'take advantage' of the new camera - that it's
a waste if you don't spend $2K on a zoom - and that's the myth. The Tamron will perform better on the new camera than it did on the old, that's almost guaranteed, unless you have an out-of-spec Tamron.
You can get the 3x as expensive Pentax/Nion 70-200 2.8 if you want, and you may see a slight improvement over the Tamron - but those $$ lenses are not required to see an improvement over the previous camera. If you're interested in 'maximizing' the difference, sure, get the $2K zoom, but that absolute maximization of MTFwill probably bring more diminishing returns than you'd be comfortable with, for that price. If the Pentax focused faster, more accurately, or had a better MFD, something like that, that might be a better reason to get it vs. any resolution difference. (It's not likeley to have better bokeh - that Tamron is a bokeh monster.)
More and more I think spending uber-$$$ on glass is the waste of money, not the other way around. Get good glass (not the 'best',) get the best sensor you're comfortable buying, then you'll see the best IQ returns at any given time.