copied from the contax g user pages , another opinion ,
[ below in quotations]
in mho
the g lenses are very highly regarded wherever an opinion has been offered ,
ive got the 45 and the 90 and i feel they are both the best of breed
exceeding even leica at least in sharpness.... if not build quality, bokeh and color rendition where some feel leica has an edge
copied
" ...........Contax G and Leica: Image Quality
Thanks for taking the time to provide such a detailed comparison between these two fine cameras. If you don't mind, I have a few quick follow-up questions for you. One - do you feel that the image quality produced by the G2 is comparable with that of the M6. I understand that these are very different animals, and that all lenses produce slightly warmer/colder effects, but are the images of comparable sharpness/contrast etc.?
I don't currently own an M Leica (I think I sold my M4-P system in about 1990), so I can't answer this question by making side-by-side comparisons. All I can do is look at pictures in my files that I shot with my various M's and lenses, and compare them to ones I've shot more recently with the G's. This poses the risk of some distortions: for example, films have improved over the years, and this might make current pictures look better than older ones for reasons that have nothing to do with the quality of the cameras or lenses. And it's possible that my shooting technique has gotten better... although then again, it may have gotten worse!
Still, keeping these caveats in mind, I'd have to say that my overall impression is that the G's image quality is at least equal to the images I got from the Leica, and in many cases it's significantly better. This doesn't really surprise me, for a couple of reasons:
-- All the Zeiss lenses for the G were brand-new, fresh designs taking advantage of the latest computation techniques and optical glasses; many Leica lenses are either based on old designs (some going back to the '50s!) or "ports" from the Leica SLR line, which means they can't take advantage of the shorter depth allowed by a non-SLR body.
-- All the G lenses are pretty conservative in terms of speed and specs. Yes, the 90mm f/2.8 Sonnar gives substantially better images than either the 90mm f/2 Summicron or 90mm f/2.8 Tele-Elmarit I used to have. But what else would you expect? The Summicron is a full stop faster, and high-speed lenses are harder to design; the Tele-Elmarit was designed specifically for extreme compactness and light weight, so it used a very simplified optical design (only 4 elements.)
I always considered the pictures I got with my Leica lenses very satisfactory (except occasionally from the older of my two 90mm f/2 Summicrons, which was sharp but flarey at full aperture, and from my 50mm f/1.5 Summarit, which badly flared any light sources in the picture area -- sometimes a pretty effect, but other times NOT what I wanted!) But the current G lenses seem significantly better overall. Their most striking quality to me is something I call "microcontrast" -- even small details are imaged with very clear edge definition, which gives a remarkable richness to textures such as fabric and skin. In fact, I'd say that the three G lenses I currently own (35mm f/2 I just got, 45mm f/2, and 90mm f/2.8) are the best lenses in those categories of any I've ever owned or used.
If you prefer "objective" measurement, I think you'll find my impressions are generally borne out by lens tests in back issues of 'Pop Photo' -- the G lenses have tested at least as well as and usually better than any Leica equivalents. (I put more confidence in the 'Pop Photo' tests than some of those quoted so reverently on rec.photo for two reasons: 'Pop' uses very sophisticated statistical techniques to relate its raw numbers to real-world performance; and, you can check the actual magazine articles, rather than having to just rely on net.hearsay!)
Again, though, keep in mind that sharpness isn't the only thing -- for example, if you really need an f/1.4 medium tele, the Leica system has it and the Contax G system doesn't........................"