p.3 #3 · NEX with Contax G after 28/2.8: 45/2 or 90/2.8?
loosh wrote:
I don't doubt the quality of the optics, amazing examples have proven the G series is legit. I'm wondering more about focus feel.
Well, I have not (yet) bought any of the branded adapters. I have a cheapo one - but its well-built and small (and also stylish, yes that counts too ). I leave the adapter on the NEX and switch lenses on the adapter, so I can use the original back covers and leather bags which keep everything small and (almost) pocketable.
An adapter (any) doesnt come close to a real focus ring. It is not very smooth, and I've read this about the branded ones as well. And some of the branded ons look a bit bulky compared to what I have.
So it's not smooth but can you focus optimal? I only do handheld and yes you can. I'm pretty picky about the pixel level sharpness and comparing to excellent lenses on Canon 5D2 (and I think you get in on par when youdo it good). A better ring would make it easier, but I guess this is a price you pay for size (and in this case, sometimes IQ with an edge).
EDIT: I've found that my copy of the 45 focuses a bit smoother than the 28 I have. Why this is I have no idea (the same adapter used for both).
p.3 #4 · NEX with Contax G after 28/2.8: 45/2 or 90/2.8?
I have just got a G 28. Do the rear element protection lugs have to be modified in order to get it to fit an NEX5? I am using a Kipon adapter and the lugs have marked the matt area in side the camera mount. The lugs have prevented me from mounting the lens.
p.3 #5 · NEX with Contax G after 28/2.8: 45/2 or 90/2.8?
I have a 5N and no modification. I am using what I believe is a Kipon copy (no-name). Slight marks are visible on the matt area but no problem to mount. Maybe it's the 5 vs 5N? I've heard though that some adapters wont let you mount the G21 - I think it's Philippe/philber that said so.
And BTW, congrats for the lens, it's a very strong performer on the 5N. It's what I use most out of my set containing the 45 and 90 as well.
p.3 #6 · NEX with Contax G after 28/2.8: 45/2 or 90/2.8?
I have no personal experience with G-NEX adapters (yet), but I'm interested in acquiring such a combination and I have read that for certain G lenses you need to mount the adapter to the body first and then mount the lens to the adapter. This is because the lugs will not turn inside the mount, but they will fit if the lens is mounted last (which does not involve turning the whole lens).
p.3 #8 · NEX with Contax G after 28/2.8: 45/2 or 90/2.8?
uhoh7 wrote:
My mainstay at 90 has been the tele-elmarit---the little one
That's a sweet lens. I'd been looking for a decent one without the "disease" or other problems with the glass for a while, but any of them that fall into that category have been out of my price range.
I'm picking up a CV 90 Lanthar to have a stab with. I can't imagine focusing a 90mm lens via an adapter on the NEX... seems like it would be difficult!
BTW, I have a mint Contax G 28/2.8 and Fotodiox adapter that I'm going to list for sale pretty soon if anyone is interested.
p.3 #9 · NEX with Contax G after 28/2.8: 45/2 or 90/2.8?
FWIW, when it was new, the Contax G 90 was rated by Popphoto as the best lens they'd tested in its class, but I'm sure the various Leica's in that range are similar or better in quality. Much of the Contax G 90 complaints in the past seem to be a result of the inaccurate autofocus, which skewed opinions of the lens. If you can deal with the wonky focus ring adapters, the Contax G 90 is a fantastic deal on NEX, IMO, but I'm sure I'd rather have a 90 Summicron if money was not an issue.
p.3 #10 · NEX with Contax G after 28/2.8: 45/2 or 90/2.8?
Wfrank: thanks for that. I wonder is there any harm in removing a mm off the lugs? I assume that they are there only to protect the bulbous rear element.
p.3 #12 · NEX with Contax G after 28/2.8: 45/2 or 90/2.8?
MarkJones wrote:
Dcjs: ah that's a good idea. I,ll try that. On the other hand might it be that the adapter is too thin?
The reason that there is obstruction is an issue is because of the matting around the sensor. I don't believe one adapter is better than another in regards to the clearance issues.
p.3 #13 · NEX with Contax G after 28/2.8: 45/2 or 90/2.8?
MarkJones wrote:
Wfrank: thanks for that. I wonder is there any harm in removing a mm off the lugs? I assume that they are there only to protect the bulbous rear element.
I'm sure you could. Their only purpose as far as I know is to enable you to place this rangefinder lens bottom-down on a table. Some that use it on micro 4/3 saws them off!
But see if it makes a difference mounting the adapter or lens first. In my case the adapter stays put while I change the lenses.
Next I would try another adapter first before doing such thing, you're the first one I've heard that the 28 causes a problem like that. The 21 is different.
p.3 #15 · NEX with Contax G after 28/2.8: 45/2 or 90/2.8?
Agreed, for the most part. The "deal" of the Contax G lenses is reduced quite a bit if you pay for that conversion. I don't mind using a focusing adapter for my Contax G 90, since I don't use that focal length often, so it is a lot of lens for the $150 or so that I paid for it a year or so ago.
That being said, I am considering a Contax G 35 conversion. I've gone through half a dozen different rangefinder 35mm lenses, and the Contax G 35 seems to be my favorite combination of size, IQ and speed for my everyday lens. If I get it converted to M mount, it'll still be much, much cheaper than a 35 Summicron IV, and the two are basically identical lens designs.
p.s. I probably shouldn't say this, because I don't want to mislead anyone, but I'm suspecting that the Contax G 35 may be performing a little better at the edges with the 5N compared to the 5. I'll have to find time to test it a bit, in case I'm just imagining it.
p.3 #16 · NEX with Contax G after 28/2.8: 45/2 or 90/2.8?
I liked the Contax G 45 Planar so much, that I purchased the lens on 2 occasions to study the feasibility of converting it to M mount and therefore to NEX. On both times, I gave up. I still think it could be done, but there is so much time one can spend on something like that.
At least on the G45 Planar, the entire assembly, front and back lens groups and aperture can be removed from the bulk of the G screw method focusing mount in a neat small package. There is a small lever that operates the aperture. I had mounted it in a donor Canon LTM 50/1.8 helical mount for testing on my M8. The problem was making the front end with an aperture control ring.
Japan Exposures remount solution does not give aperture click stops and the front filter barrel rotates when focusing, so for the price I don't feel that is an effective solution.
With the backward direction focusing adapters, being also not very precision, I gave up, thinking the ZM Planar is a more reasonable solution.
p.3 #17 · NEX with Contax G after 28/2.8: 45/2 or 90/2.8?
Yeah, I think I can deal with the aperture without click stops. Apparently, Hawk's factory may also do conversions, and I'm going to check into that. I've owned both ZM 35s, as well as others, and the Contax seems the best middle ground between size, speed and IQ. The ZM 35/2 was just to large for my everyday lens, and I've got the ZM 50/1.5 for tele/portrait.
p.3 #18 · NEX with Contax G after 28/2.8: 45/2 or 90/2.8?
From my limited knowledge of reading MTF charts, I believe the Contax G lenses to have higher microcontrast versus the ZM version out to 14-16mm image height, working well with the 1.5x sensor. http://farm7.staticflickr.com/6005/5992317024_4ebcf621c2_z.jpg
p.3 #19 · NEX with Contax G after 28/2.8: 45/2 or 90/2.8?
I read recently somewhere that someone was having a G 90 converted to Leica screw mount to use with a Hawk's adapter (I presume with M adapter also). But how would you focus it, via the Hawks motion?
p.3 #20 · NEX with Contax G after 28/2.8: 45/2 or 90/2.8?
Hi Jim, yes, fine detail rendition goes to the Contax G in your charts, and at f4 it will be the main difference, with some loss of consistency from mid-frame, but since this is at a high level already...
You see the usual Contax effect of stopping down boosting microcontrast impressively, as compared with more modern designs. Using image centre data from f2 -> f4, we see the Contax 40 lpmm move from t=.55 to t=.72, and the ZM from t=.51 -> t=.62, so higher to start out then a much better (and significant in image terms) improvement to f4.
Anything over t=.6 for this line pair is excellent. Looking at the cliff face commencing at 17mm at f4 in both these lenses, two things to say: both are great for APS-C coverage, and expect them both to clean up the corners in FF at f5.6-f8, at least for resolution alone.
Also visible is Zeiss's emphasis on very high 10 lpmm lines in post-Contax lenses wide open, giving a more brilliant Leica-like image, but it's a necessary though not sufficient condition for overall image excellence. All IMO, of course.
To add a little more, in MTF it's all 'micro-contrast', but the term works best for fine detail (the 'micro' part) whereas in higher data for lower spatial freqencies (10,20) you can observe higher contrast (lens performance) for lower contrast objects in that size group. In these days of ultra sophisticated post processing, and fabulous sensor resolution (compared with the 'sensors' of the Contax lenses' day - 35mm film), the 40 lpmm will be more and more important, moving forward.
). I leave the adapter on the NEX and switch lenses on the adapter, so I can use the original back covers and leather bags which keep everything small and (almost) pocketable. 
