A7r with RF glass

My main concern about the Sony bodies has been how well they'll work with 35mm M lenses. I'd ordered an A7r, but following advice from RFF and LUF re: corner smearing and vignetting, I returned it unopened and got an A7.

Today I tried the Summilux Asph FLE, two Mandler designs – 35 pre-aspherical Summilux and 35 Summicron v4 – and a 40mm Summicron. I tried them at widest aperture to f4, thinking that the A7, with better high ISO performance, would be my body of choice for low-light-level shooting. (When I can use lower ISO's, I'll stick with M9.) I used a Voigtlander adapter, which is quite solid. I photographed a blank garage door to look for color vignetting, and a fence with both vertical lines and mesh to check for corner smearing.

I tried the Lux FLE first with high hopes, but it exhibited some color vignetting at all apertures and quite a bit of corner smearing: lots of it at f1.4, moderate at f2.8, and perhaps just tolerable at f4. I won't be using this lens on A7.

The 35 Cron v 4 performed better than the FLE, but still not too well. At f2 I saw moderate color shift, and vignetting in the corners. At f4 it was still vignetting, but the color shift seemed less. At f2 it smeared less in the corners than the FLE – smearing was limited to the far corners of the frame. At f4 it might be tolerable, but it's so much better on M9.

The 35 pre-aspherical Summilux and the 40 Summicron were both better, but for different reasons.

The PA Lux at f1.4 showed quite a bit of luminance/BW vignetting but much less color shift in the corners. This is probably be reparable in LR/PS withe the regular vignetting correction tool (no need, I'm guessing, for the new and complicated flat field plug-in). It showed only a little bit of corner smearing at f1.4 and f2, and none at f4. IMO this is a usable 35mm lens for A7 when one needs wider apertures.

The 40 Cron Was best-of-all for avoiding smeared corners – visible only in the extreme corners at f2 and f2.8; none at f4. When looking at the 100% crops of the corners I could tell I was looking at symmetrical bokeh, not elongated smear. The downside, however, was that this lens vignetted quite a bit – luminance vignetting without serious color shift – even at f4. Perhaps it wasn't comfortable in the Voigtlander adapter, and I wonder if Novoflex would be just be the same. (It doesn't do this on M9, because it's been coded to use the 35 Cron lens profile.)

My own conclusion is that I won't be using the 35 Cron v4 or the Lux Asph FLE on the A7 body, and will probably make the 40 Cron my regular moderate wide angle. Subjectively I like the PA Lux best of all, but am always afraid of its characteristic moon-shaped flare when there's a light source just outside the frame.

These are tentative first-days-with-the-camera pixel-peeping checks to see what lenses to go ahead and use. I might change my mind later.

I'm also going to check some 50s this weekend. A first look suggested the pre-aspherical Lux performs noticeably better in the corners than 1.5 Sonnar-C. My Lux is a minty black paint one, worth quit a bit more than either an A7 or A7r body; so I wish it had turned out the other way!

Kirk
 
Litz, an operatic busker in San Francisco's Maiden Lane

Sony A7 – 40 Summicron (no corner vignetting or smearing with this lens.)

I plan to use the A7 with 'classic' rather than modern M lenses.

Kirk

11490500295_9081de1188_o.jpg
[/url]
Litz, an operatic busker by thompsonkirk, on Flickr[/IMG]
 
Some 'classic' 50s on A7

Today I pixel-peeped five 'classic' M-mount lenses on the Sony A7, going from widest aperture down to f4 (not going smaller than f4 on the assumption that M9 is my camera body for anything but low light). I was looking for both color vignetting and corner smearing. I'm taking 'classic' to mean style of rendering, not necessarily age. I'm using A7 instead of A7r because of advice here and on LUF that A7 is better with Leica lnses. They were:

--Pre-aspherical Summilux
--2007 1.5 Sonnar-C
--2.8 Elmar, last issue, with modern coating and fewer aperture blades
--5cm 1.4 Nikkor for Nikon S rangefinders, in Amadeo mount
--Millennium Nikkor-S in Amadeo mount

Pre-asph Lux: Best of the bunch. Luminance (BW) vignetting moves from dark to slight between f1.4 and 4, but there's no color shift in the corners. At f1.4, moderate corner smearing and noticeable chromatic aberration, but the smearing disappears entirely by f4.

Sonnar-C: Unacceptable. Lots of BW vignetting and Blue Channel color shift (hereafter B/CS) at f1.4; these characteristics continue to f4 with the B/CS actually increasing. Smearing and marked CA at f1.5; smearing decreases but doesn't go away at f4.

2.8 Elmar: BW vignetting and B/CS at f2.8; gentler BW vig at f4, but continuing B/CS. Always a bit of corner smear – not as good as the pre-A Lux, though much better than the Sonnar-C.

Vintage Nikkor: Lots of BW vig with no color shift at f1.4; B/CS increases as you stop down. From f1.4 to 4, soft corners, flare, and smearing. Unacceptable on A7 except as an interesting 'special effects' antique-looking lens. (Much nicer on M9!)

Millennium Nikkor: BW vig at f1.4, but no color shift. Slight B/CS appears at f4. Smears in corners at f1.4 and 2, decreasing to very little at 4.

Overall, corner color shift appeared primarily in the Blue channel, according to LR RGB measurements. I was surprised to see very little in the Red channel. Maybe that's a problem with A7r more than A7? .

I'll be using the 2.8 Elmar on A7 more than my peeping might suggest. In low light and high ISO at f2.8, it has enough DOF to use with focus-peaking; and the dark corners almost cover up the B/CS and look almost natural in low-light situations – as if one's eyes are focusing on the center of the image in the relative darkness. It's smaller and lighter; and I'm comfortable carrying it in my pocket, whereas my black-paint pre-A Lux and Millennium Nikkor are too minty for that sort of treatment.

The Sonnar-C's performance was a disappointment to me. I thought that using it with Sony focus peaking would avoid its problem of focus shift and make it a generally usable and not too fancy 50mm lens with nice bokeh.

Kirk
 
I thought the cron would look good but it seems a little soft here...and the color rendered looks pale.
accessing a lens and a camera from a single shot is.....

I like the photo, but I don't expect brilliant color and razor sharpness out of the shadows in an underground garage.

anyway, had my cron on today too, 28 that is 🙂


DSC02080 by unoh7, on Flickr


DSC02082-2 by unoh7, on Flickr

both f/2

here is the 50 cron with some light:

DSC01162 by unoh7, on Flickr
full size:
http://farm4.staticflickr.com/3808/11490511246_c21ceec3ae_o.jpg
maybe soft for you, but looks good to me 🙂
 
I'm just about to make the A7 plunge, can someone please summarize the options/opinions for lens adapters - there are so many and the price range is huge? I'm looking for inexpensive adapters for Canon EF, Nikkor AI-s, and Leica M and LTM lenses? Thank you, thank you!
 
I'm just about to make the A7 plunge, can someone please summarize the options/opinions for lens adapters - there are so many and the price range is huge? I'm looking for inexpensive adapters for Canon EF, Nikkor AI-s, and Leica M and LTM lenses? Thank you, thank you!

EBay has huge selection basically all mounts, from between 15USD and 25USD, for perfectly fine adapters, though they will most all go past infinity a touch.

A few obscure mounts are more expensive, and there are high quallity and close focus mounts which are much more expensive.

I have many cheap ones and they are fine.

A7 28cron:

DSC03737-2 by unoh7, on Flickr


DSC03736 by unoh7, on Flickr


DSC03728-2 by unoh7, on Flickr
 
Back
Top Bottom