edwardkaraa wrote:
Well this is one aspect that is quite important as well. Though at close range color shift seems to be minimal and sometimes undetectable.
I felt close range performance of the problematic Zeiss Biogons was decently solid on the NEX even though distance/infinity performance at times left something on the table and chalked that up to being as subject focus draws closer the rear element is moved forward from the sensor enough to make a difference.
michaelwatkins wrote:
I felt close range performance of the problematic Zeiss Biogons was decently solid on the NEX even though distance/infinity performance at times left something on the table and chalked that up to being as subject focus draws closer the rear element is moved forward from the sensor enough to make a difference.
Agreed. The ZM wides show some color shift at infinity, but none at medium and close range. I don't know about smearing as the sensor of the M9 is so well tuned for RF wides. so basically it's nice to see how the lenses behave at close range, but also at infinity where most corner problems happen.
Calm down people. Corners are just... corners. No need to worry for a possible problem, unless it proves to be a real problem ( i.e. you've got the complete range of ZM and G Biogon lenses in your cupboard. )
artur5 wrote:
Calm down people. Corners are just... corners. No need to worry for a possible problem, unless it proves to be a real problem ( i.e. you've got the complete range of ZM and G Biogon lenses in your cupboard. )
What me worry?
Problem solved, early this year I sold three Biogons. Wish I'd kept my ZM18 Distagon though... I want to see that one for myself on an A7 or A7r. Hmnn... maybe on Nov 10 I can arrange that.
sebboh wrote:
thanks for extra info. a few questions/comments regarding the shots.
1) did you focus and then recompose or did you move the magnified area over to the bridge without changing final framing? i ask because in some cases focus is cleary at the the back of the bridge and in other photos it is clearly in front of the bridge. in my own experience with NEX cameras i find that focusing in magnified mode is more accurate with peaking off btw.
2) it appears to be a bit crooked as the in focus area slants. funny jpeg settings make it difficult to follow the plane of focus though. if you want to check it i suggest shooting at infinity with a slanted horizon so it passes through opposite corners (2 shots slanted opposite ways). if some corners are noticeably worse than others, either your lens or your adapter is decentered.
4) it appears that from you stopped down sample with the oly 18/3.5 that the central portion is much less sharp then the edges, which is very odd. perhaps it has a fair bit of field curvature.
1) I moved the magnified area on the LCD without moving the camera; and I checked with every aperture to avoid possible focus shift problems
2) I'll try that, thanks
Just to be fair, the ZF 35/2 gives a tad of color shift on the Nikon D700 too. I don't think you can get a perfectly uniform frame, color-wise on any digital camera, except for very long tele lenses.
douglasf13 wrote:
There's a little bit of color shift with the RX1, too, FWIW.
Yep, there is. The only reason I point it out is that this is with a slow, native moderate wide angle designed for the A7r. I would imagine pretty much anything else is going to be an issue if even this 2.8 Sonnar 35 is beginning to show color vignetting. This makes me really curious about the implications for either wider or faster FF native lenses on these cameras.
'..gives a tad of color shift on the Nikon D700 too.'
Of course you could always revert to trouble-free, perfectly accurate colour film...why should the corners have all the fun when the whole frame can be awash with Disneyland colourscapes dreamed up in Fuji's or Kodak's labs.
Makten wrote:
Just to be fair, the ZF 35/2 gives a tad of color shift on the Nikon D700 too. I don't think you can get a perfectly uniform frame, color-wise on any digital camera, except for very long tele lenses.
Not much difference there. The normal 300mm modern lenses are ~105-115mm rear end main lens constructions. The 400/2.8VR is maybe 5-15mm longer. Almost everything in that huge front end is a front-mounted afocal tele-converter, like the biggest eye-piece you've ever seen. The likes of the 85/1.4 is actually a harder strain on angle-sensitivity (though mechanical shading removes the worst cross-angles...)
To make the concept really acceptable for WA users, they'll have to come up with a kind of in-between optical construction IMO. Not quite as retrofocal as a full Distagon construction, but longer (longer exit pupil distance, more pupil magnification) than a symmetrical 35.
-Or get on with it and actually spend some money on stabilizing and optimizing the organic sensor solutions.
He states the A7 is far better with the ZM 21 2.8 and the Voigtlaender 15mm than that A7R.
Comparing Ron's A7 samples to Leo's A7r samples with the CV15 lead me to the same conclusion, especially considering that Leo's shot is not focussed at infinity where problems are the worst (because at infinity the exit pupil is as close to the sensor as it gets).
IMHO the A7r samples show more astigmatism than the A7 but it is quite difficult to judge from the A7r samples so far.
Yeah, Steve will post lots of samples with the ZM21 and other lenses in 5 hours.
Curious to see how the direct comparison will be..
At least he has both cameras at the same time ;-)
He states the A7 is far better with the ZM 21 2.8 and the Voigtlaender 15mm than that A7R.
I would not trust this guy with his usual procedure: comparing images at 100%.
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