Thanks for asking. ..
I may not afford f1.4G now, but still hovering around whether to buy f1.8G or not...so looking for better reasons to buy it, trying to convinced myself...it just me... ;-)
90% of my time I'm using 24-70...now there are friends 'chieo' me for model shoot. I can still use this lens, no problem with it. Just that lots of user praising this 85 best for model....so hands started to itch loh...lol....
Well, 85mm is indeed one of the "standard" prime lens for portraiture, but calling it a "best for model" or "model lens" sounds stupid enough :bsmilie:
Reason why 85mm is a favorite, is first it's FOV is decently tight for a half-body portrait or if you stand closer, maybe a head-to-shoulder kind of portrait shot. Most 85mm primes have negligible distortions so you don't need to worry if you'll get distortions at the edges compared to a 35mm or even 50mm focal length, or even a zoom lens' barrel distortion (primes generally suffer less barrel distortion, and the 85mm is really near negligible).
Primes is also generally known to have better IQ than zooms, and also it's fast if you are aiming for some bokehlicious portrait or subject isolation or using natural light under low light conditions.
If you don't know what you're buying into, you won't notice the difference between your shot with the 24-70 zoom and this 85mm prime and soon you'll wonder what you've been paying for, even if it's $100 (of course the 85mm isn't this cheap) and if you're wasting money.
Generally I have no problems with the 85mm f/1.8G. I've owned both the 85mm f/1.4G and 85mm f/1.8G. I can safely tell you, it works fine on my D800E and the f/1.8 performs as good as the f/1.4. Of course, the f/1.4G have advantage at wide open sharpness but it's not like heaven-and-earth difference. Their sharpness level are both at excellent range of the MTF chart when stopped down to f/5.6.
My advise is, unless you really have a thing for 1) The gold ring, 2) You need weather sealing 3) The 9 blade aperture and being very anal about the OOF "bokeh balls", then pay for the f/1.4G. If not, you can get the f/1.8 at about 30-35% of the f/1.4G
