Now that the new Sony A7 and A7r have been announced we all want to know about their performance with wide-angle range-finder type of lenses (35mm and below). On APS-C Nexes they have problems in various degrees with corners/edges; smearing and color casts.
Reading the early specs the A7r seem to have an advantage over the A7 as it has "off-set microlenses". Sony illustrates it like this; to the left traditional surface and to the right off-set micro lenses to better harvest light coming in with a steeper angle.
Please share any findings on the subject.
The first WA RF shot I've seen, A7r with Zeiss ZM 18/4: LINK
Lots of PP, cropped and way too small. But it's a first. Found in one of the links posted in the mega-prayer-thread. "Brian Smith Pictures".
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U P D A T E - NOV 22 - 112 pages later
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This thread asked for it and got its fair share of speculation and corner pixel peeping galore @ 36MP. Summary:
- A7 is clearly better than A7r for WA RF lenses
- Many RF lenses below 35 show corner/edge issues (*), worse so on A7r than on A7.
- Most RF lenses above 35mm seem just fine
(- SLR lenses all seem fine, including WAs)
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(*) many of the RF WA lenses deemed unusable for landscaping will perform just excellent for short DOF photography.
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Two very fine cameras indeed. For me personally 24MP no doubt, not only because of WA RF's performance.
These cameras are not Leica replacements. Leica fosters better for the type of lenses particular for this thread. In house software corrections are part of that but not all. Leica is still Leica. But the Sonys bring superior resolution, dynamic range, size advantage, and usability to the table. Add to that within parenthesis, (affordability).
Thanks, that page loads really slow but he seem to check a lot of lenses. How did you find out, through an image (link?) or google-translating the page?
Okay, here's the quote mentioning it: "Full frame Leica M bayonet adapter today becomes very interesting. Unfortunately, this Zeiss lens A7R 21mmF2.8ZM on the left and right sides of the screen there will be a slight redshift."
"Slight redshift" sounds better than expected but no example image. We have to settle with an image of the ZM21 mounted on the cam. LINK
Makten wrote:
Where can we find this info? And why would they make the sensors act different?
Too bad if it's true, because I really don't want 36 mpix.
It's not that I don't want 36MP, but I just don't need them. 24 is enough already, but if this is true I'm certainly not getting an A7.
It was covered in the Sony Australia release video, among other places. The A7r's gapless, offset microlenses and lack of AA filter will be better with highly angled rays of light. A7r also has magnesium front plate, as opposed to A7's plastic front plate, but A7r doesn't have on senser PDAF.
Makten wrote:
Where can we find this info? And why would they make the sensors act different?
Too bad if it's true, because I really don't want 36 mpix.
According to Jim Fisher, over rangefinderforum, after having had a hands-on experience with both, "It is my understanding that both the 7 & 7R use offset mircorlenses. The 7R sensor is a gapless design, the 7 is not". He says that he will be asking, though.
douglasf13 wrote:
It was covered in the Sony Australia release video, among other places. The A7r's gapless, offset microlenses and lack of AA filter will be better with highly angled rays of light. A7r also has magnesium front plate, as opposed to A7's plastic front plate, but A7r doesn't have on senser PDAF.
I probably won't use AF lenses at all, so that's not a problem. But I don't want to buy a new computer just to be able to handle huge files either. On the other hand, I take very few pictures per day, so as long as it works without crashing, I could probably live with it. Moire is not a concern most of the time I guess.
There still is a small chance that the offset micro lenses was needed to make the smaller pixels cope with certain lenses, while the 24 mpix version perhaps is fine as well.
You've still got an AA filter in the way, so astigmatism will likely be a problem. I'd bet the A7r performs better at the edges even with native lenses, let alone M wides.
Makten wrote:
I probably won't use AF lenses at all, so that's not a problem. But I don't want to buy a new computer just to be able to handle huge files either. On the other hand, I take very few pictures per day, so as long as it works without crashing, I could probably live with it. Moire is not a concern most of the time I guess.
There still is a small chance that the offset micro lenses was needed to make the smaller pixels cope with certain lenses, while the 24 mpix version perhaps is fine as well.
wfrank wrote:
...Reading the early specs the A7r seem to have an advantage over the A7 as it has "off-set microlenses". Sony illustrates it like this; to the left traditional surface and to the right off-set micro lenses to better harvest light coming in with a steeper angle.
...
:-/
So image side telecentric lenses or very long lenses like the Novoflex 400/5.6 and such will result in dark corners.
Whats about micro-wedges like Mr. Fossum has described it :-(
The ZM18 shot from Brian Smith shows a magenta cast, and it's cropped. I have no idea what part of the original image we're looking at, but I only see the cast on the left side.
I can't imagine that there won't be a magenta cast on even some 35mm M lenses. Leica requires the use of in-camera software correction to deal with this. Fortunately, there are a few software options to fix color shift.
The bigger issue, to me, is smearing, so we'll need some proper tests.
