When you say 1 stop better, are you just talking about sensor noise performance or AF sensor performance?
My question is purely about sensor performance and why f2.8 will stay that important forever.There is also another thing that you may not think of, is that lenses wide open generally don't perform their best.
... unless you're scraping together the money for a Canon 24-70L2basically having a wide aperture available is like a condom
its better to have it and not need it than to need it and not have it
Ok, thanks for the answer from a real world pro, so you're on the side that even f2.8 isn't really "fast" enough and it just happens so that the fastest zooms available are f2.8. So if I understand you correctly you'd rather go with a Tamron f2.8 + a faster prime like the Sigma 35mm than a Canon 24-70/f2.8 for the price of both combined?
only a part time pro
unfortunately have to work a real job too
well I would happily pay $10,000 if canon made a 35-85 f2L IS that was razor sharp wide open
It would almost NEVER leave my 5Dmk3 and I could sell most of my primes
typically i'll shoot my 1.4 primes at f2 anyway as very often DoF at 1.4 is too thin however saying that if shooting an event in very low light with no flash even at iso 12800 i'll still be at f1.4 but really at those high iso
any sharpness differences between apertures are completely negated by the noise and loss of DR. In these situations there would be a real benefit of having f1.2 lenses
as for the tamron well I've had bad tamron encounters in the past so i'm really gun shy about this lens and have a somewhat prejudiced opinion which isnt helped when people report front elements falling out
Personally I think the 24-105L and say a sigma 35 f1.4 would be a more reliable combo
the 24-105L with some flash is a superb lens tough and very versitile and when f4 aint enough then swap over to the 35. If f4 isnt enough it doent take too much more light loss to make f2.8 not enough.
a neat trick with event photography is use a slower shutter speed to balance the ambient while keeping a decent iso like 1600 or even 3200 and using second curtain flash to freeze the subject these sort of techniques work great with f4 lenses (the IS on the lens helps reduce camera shake of the background and ambient while the flash takes care of the exposure and freezing the people. (look up dragging the shutter on google)
not to mention its basically impossible to take a good shot of half a dozen people at f1.4 either as only 1 person will have their nose in focus.
As with everything in photography the key is having a good understanding of the gear you are using, know its limits and work witin those limits. its only once you go beyond those limits that things get ugly
My wife however doesnt like shooting primes and so she prefers to use the 24-70L f2.8 mk1 over the primes
we are patiently waiting for the 24-70 f2.8L IS if it ever shows up or perhaps a sigma version to try out if that turns up