Rob-downunder said:Thanks for your replies so far. To answer one question - yes I shoot in raw and process in Lightroom. My ideal solution would be a 24-105 mkii with equivalent sharpness to the other recent releases from Canon, but it doesn't seem likely this is going to be released. Purchasing the 6D with 24-105 plus the 16-35 f4 will cost in the vicinity of $4000 aus, which I am prepared to pay to get the quality if the 24-105 on FF will deliver significantly sharper images than the 18-135 STM on crop. However if this isn't the case then I can probably do a 7d mkii body and keep the rest of my kit for around $1500 aus (guessing at the price here).
I accept the 24-104 won't be in quite the same league as the other 2 L zooms, but will it be significantly better than what I have now?
I have a 6D and Sigma 24-105 f/4 Art lens. Considering it's a zoom, it's almost as good as a prime at any focal length you choose. I little post processing for barrel, pin cushion, vignette, and- BAM! You've got a real keeper. Sharpness is excellent, and there's no way to correct an unsharp photo.