I just did this comparison for my purposes, but I thought others might be interested in this as well. I recently sold my xpro1 and bought an nex 7. I had conceded that the Contax G 21mm wasn't going to work out well with the 7, but I decided to test it with the Adobe flat field plug in anyway. I was surprised that it actually looked pretty good after conversion so I decided to test it against two SLR lenses that I had planned on using occasionally with the 7. Here's what was tested:
This one surprised me. While they are all soft, the G21 performs the best. I'll leave it up to you to decide whether this is good, good enough, or inadequate for your uses. I just thought it was interesting since prevailing wisdom is that retrofocus wide angle lenses will perform better with the NEX 7. The G did of course require "cornerfix" but with the lightroom plugin, this is pretty painless.
Next, I will have to compare the results between the 7 and 5n to determine how I will actually use this lens. I planned on having it permanently mounted to the 5n, but now I think it's at least useable on the 7 and certainly better than either of these SLR options.
I need to learn more about "cornerfix" (only recently heard of it) as I've got some lens combinations that can also be an issue similar to your example.
RustyBug wrote:
I need to learn more about "cornerfix" (only recently heard of it) as I've got some lens combinations that can also be an issue similar to your example.
I've got LR4, but mostly work CS6 ... tips
LR4 has the functionally built-in, if you download the flat field plug in, although I haven't used it to compare.
Rusty, there's the stand alone cornerfix program that you can download and run on its own or the adobe version which is called flat field. I don't know if the adobe version works with acr/photoshop. I think its lightroom only. Both programs require you to convert the raws to dng first. With Lightroom, you can do this automatically on import. With photoshop you will probably have to use their stand alone dng converter first.
The G21 is a lot less purple in the corners on a 5N. For what its worth, when I was using a 5N more, I ended up trying many 20mm-ish (G21, zuiko 21 & 24, sigma19, rokkor 20 &24). In the end, the 18ZM was what I ended up with and its rendering style wasn't too far off from the rest of the contaxG's.
