I just tested my Zeiss Contax G 35mm Planar with Fotodiox adapter on my NEX-7. In short, there is minimal real world color shift, but the lens suffers from very soft corners at wide apertures just like the ZM 35 Biogon. The ZM 35 seems to have noticeable color shift on the examples I've seen. For reference, my ZM 50 Planar is sharp everywhere wide open.
Here are the results, all shot from a tripod with delay.
First, the white tissue test:
http://sheltons.net/temp/35g/DSC00659.jpg
http://sheltons.net/temp/35g/DSC00660.jpg
http://sheltons.net/temp/35g/DSC00661.jpg
Very little vignetting or color shift apparent at f/2. The real-world shots look fine.
Next, the full frame test shot at f/8:
http://sheltons.net/temp/35g/DSC00666.jpg
Here are 100% crops from the frame center at f/2, f/2.8, f/4, f/5.6, and f/8:
http://sheltons.net/temp/35g/35gCenter-1.jpg
http://sheltons.net/temp/35g/35gCenter-2.jpg
http://sheltons.net/temp/35g/35gCenter-3.jpg
http://sheltons.net/temp/35g/35gCenter-4.jpg
http://sheltons.net/temp/35g/35gCenter-5.jpg
The frame center looks pretty good to me from f/2.8 or certainly f/4 for most purposes. However, the corners and edges are pretty soft up to f/4, or even f/5.6, depending on your needs. Here are 100% crops from the upper left edge at f/2, f/2.8, f/4, f/5.6, and f/8:
http://sheltons.net/temp/35g/35g edge-1.jpg
http://sheltons.net/temp/35g/35g edge-2.jpg
http://sheltons.net/temp/35g/35g edge-3.jpg
http://sheltons.net/temp/35g/35g edge-4.jpg
http://sheltons.net/temp/35g/35g edge-5.jpg
Overall, I'm happy with the performance, since I tend to shoot this FL at f/5.6 or f/8. Unfortunately, I haven't shot this lens on any other camera, so I can't say how sharp it should be.
Given the ZM 35 NEX-7 vs 5n tests, I suspect this lens would perform much better on the 5n.
The center certainly looks good after F2 but that edge looks rough, particularly given that its halfway between the center and the corner. I think the corner would be really poor. Even the last border crop shows a lot of false information/ artifacts - no real detail as seen in the best center crop - almost like over sharpening artifacts when the actual detail is missing.
I think it does look fine with that shot but I also get the impression that the full potential of both the sensor and the lens are not being used at the border.
Tariq Gibran wrote:
I think it does look fine with that shot but I also get the impression that the full potential of both the sensor and the lens are not being used at the border.
I totally agree. Looking forward to the NEX-7n or NEX-6 with the 5n sensor
Back for another installment of NEX-7 lens tests...
There aren't many non-slr lens choices for the NEX-7 in the 20-25mm range. I have been comparing the ZA E 24mm and the PenF 25mm f/4, and the differences became quickly apparent. First, the ZA is a very modern design -- very sharp and contrasty from wide open to f/8. I think it's suitable for even landscape use even at f/2 - f/2.8. It has lots of CA, which is generally easily corrected in LR3 (R/C -24; B/Y +12).
The PenF is old, and not that well coated. It suffers from some purple corners and smearing on the 7. Although it's images always looked rich and contrasty to me, when I compared the PenF to the ZA, the ZA revealed much more contrast and micro-contrast, and was somewhat sharper in the center, and much sharper in the corners -- almost as sharp as my ZM 50 Planar.
I guess it makes sense -- a $200 40-year old lens isn't quite as sharp and contrasty as a $1,000 modern lens, but the PenF is a fine lens on its own.
I shot a quick comparison on a cloudy, low-contrast day. First is the overall frame at f/5.6 from the ZA:
http://sheltons.net/temp/p25vZA24/DSC01085.jpg
Next are the centers at 100%, ZA on the left. I used Cornerfix on the PenF. Notice the contrast differences in the bushes and trees, especially the yellow areas. Results in bright sunshine are somewhat more remarkable, where fine resolution jumps from the ZA images, while the PenF looks sharp but doesn't reveal broad contrast or micro-contrast to nearly the same degree.
http://sheltons.net/temp/p25vZA24/center.jpg
Here's a crop from the right edge. The PenF faded out badly in the low contrast mist, whereas the ZA held it's sharpness and contrast pretty well. It looks a bit like flare -- neither lens had a hood on:
http://sheltons.net/temp/p25vZA24/rtedge.jpg
I really like the ZA, and it's nice to have AF on a walkaround lens as well...
Sorry to have to repeat what has been said over and over, but viewing 100% crops of high-pixel-density cameras is just not a way to compare them. Because the NEX 7 has more pixels than the 5N, its crops will look worse, all other things being equal. I just picked up a NEX 7, and, when I viewed my first pics in Lightroom, and used the 100% view feature, I was immediately struck by the significantly greater magnification over the 5N.
That said, even one pic was enough to show massive colour shift with my beloved ZM 18. I had no doubt this would happen, but there's no harm in hoping...:-(
I think crops are a reasonable way to compare two similar lenses on the same camera, shot in the same conditions at the same time. I agree it's difficult to compare two cameras this way. But, in the case above, it was interesting for me to see the contrast differences in particular.
I shot the ZA vs PenF in the sun yesterday, and you can easily see a material difference in landscapes. The ZA shots look like the saturation, clarity, and contrast have been cranked up vs the PenF. I was really surprised there was that much of a difference, because I had really enjoyed the PenF!
Sorry to hear about your ZM18. I would love to have that lens on my NEX. I guess it will have to wait for the 7n -- I need the viewfinder, and the 5n viewfinder is just too big for me. I love the 7's mechanical design.
I think a lot of us would love to see some resolution tests between the 5N and 7 with rangefinder lenses at 35mm and wider, as that's where the edge resolution comes into question. Thanks!
Yes, and it certainly helps as it is flare prone. In the case above, it was heavily overcast so I didn't think I needed it. I think the same comparison with hoods would have brought the Pen a bit closer. However, the overall contrast and micro-contrast difference between the lenses is substantial.
The Pen is still a great value IMO, and only has modest purple corner issues on the NEX-7. Certainly better with purple corner issues than any 20-25mm RF lenses I've seen, and it's about the same size. I still feel the need run images taken with it through Cornerfix, however.
Smiert Spionam wrote:
Have you tried putting a hood on the Pen-F lens? I haven't shot the 25/4, but other Pen lenses I've used really benefited from a hood.
I think a lot of us would love to see some resolution tests between the 5N and 7 with rangefinder lenses at 35mm and wider, as that's where the edge resolution comes into question. Thanks!
+1
I just got the 5n, and keep thinking about the 7, but am afraid it won't work well on my WA MF lenses. The 5n has a weaker AA filter than the 7, so that should also help it close the gap in showing fine details with really sharp lenses like the Contax g lenses.
One really big open issue in my mind, is how much the 7 really helps for shooting with manual focus lenses with RAW. On the 5n, I shoot in shutter priority exclusively. The "dial" for shutter is the main dial on the back of the 5n. The "dial" for aperature is on the lens. I have the right button programmed to change ISO. What else do you need for most situations? I don't think the tri-dial would help much for MF + RAW.
On the same token, one thing really annoys me with the 5n. I use the histogram to get the best exposure. If I pull up the iso setting, the histogram cannot be viewed. I would love to be able to adjust ISO, with the histogram active. Anyone know a work-around (besides auto-iso)? HOw about the NEX 7, same behavior?
I just got the 5n, and keep thinking about the 7, but am afraid it won't work well on my WA MF lenses. The 5n has a weaker AA filter than the 7, so that should also help it close the gap in showing fine details with really sharp lenses like the Contax g lenses.
One really big open issue in my mind, is how much the 7 really helps for shooting with manual focus lenses with RAW. On the 5n, I shoot in shutter priority exclusively. The "dial" for shutter is the main dial on the back of the 5n. The "dial" for aperature is on the lens. I have the right button programmed to change ISO. What else do you need for most situations? I don't think the tri-dial would help much for MF + RAW.
On the same token, one thing really annoys me with the 5n. I use the histogram to get the best exposure. If I pull up the iso setting, the histogram cannot be viewed. I would love to be able to adjust ISO, with the histogram active. Anyone know a work-around (besides auto-iso)? HOw about the NEX 7, same behavior? ...Show more →
I completely agree. If you're shooting RAW and using manual lenses, the extra dials of the NEX-7 aren't as drastic of an improvement as they would be using native lenses, since we have aperture rings on our lenses and plenty of programmable buttons.
I agree that it is annoying when the histogram disappears when you change ISO or Exposure Comp. I was hoping Sony would change that when going from the 5 to the 5N.
You should really consider autoISO in S mode with manual lenses. I used to shoot M mode only on the NEX-5, but, now that the 5N has autoISO that goes to 3200 (nex-7 only goes to 1600,) I use autoISO in S mode. It is basically just like using M mode with autoISO...if it were available. Pretty cool.
You should really consider autoISO in S mode with manual lenses. I used to shoot M mode only on the NEX-5, but, now that the 5N has autoISO that goes to 3200 (nex-7 only goes to 1600,) I use autoISO in S mode. It is basically just like using M mode with autoISO...if it were available. Pretty cool.
You are right, I should consider using autoISO. I am wondering, is there anyway to see what ISO the auto-ISO is choosing? I would like to monitor it, especially in low light, to try and avoid 3200 or 1600, and override it manually when I am not comfortable. Then it would be a solution that would work for me probably 95% of the time.
