p.132 #1 · Official: Sony A7 and A7R Fullframe Mirrorless
charles.K wrote:
I am not sure if this has been posted yet, but this is Roger from LensRentals, with his preliminary thoughts on revisiting the A7r Very interesting perspective!! LensRental - Roger A7r
It looks like his tests make a damn strong case for the importance of native lenses to take full advantage of the A7 sensors.
I was a bit surprised by this statement:
"At this point I did wonder if my choice of 35mm lenses might be part of the corner issues we were seeing. There are plenty of reports that wide-angle, retrofocus design lenses have problems in the corners on cameras with short flange-to-sensor distances like the A7R."
I did not think there was an issue at all with retrofocus designs but rather with more symmetrical designs. This was new info to me.
p.132 #2 · Official: Sony A7 and A7R Fullframe Mirrorless
Tariq Gibran wrote:
It looks like his tests make a damn strong case for the importance of native lenses to take full advantage of the A7 sensors.
I tell you what I was surprised by: how much better the ZE 50MP on the A7R at f2 was in the center than the ZF.2 50MP on the D800E at f5.6. Not sure what would account for that.
p.132 #3 · Official: Sony A7 and A7R Fullframe Mirrorless
alwang wrote:
I tell you what I was surprised by: how much better the ZE 50MP on the A7R at f2 was in the center than the ZF.2 50MP on the D800E at f5.6. Not sure what would account for that.
I don't know, but I speculate it may be the different ways they each have 'no' AA filter. Nikon has a two layers of lithium niobate (if I spelled that correctly) aligned at 180 degrees to cancel each other out. If I understand correctly, the A7R has none at all.
I have no idea why this might make a difference (is there an optical physicist in the house?) but it's the only thing I can think of.
p.132 #4 · Official: Sony A7 and A7R Fullframe Mirrorless
charles.K wrote:
I am not sure if this has been posted yet, but this is Roger from LensRentals, with his preliminary thoughts on revisiting the A7r Very interesting perspective!! LensRental - Roger A7r
Thanks for the new article, Roger!!
Any chance of testing a Sony 10-18 @ ~15mm on A7/R (where ever the vignette stops being a problem) ? I would be very interested how the native mount lens fares, even if it's designed for APS-C.
Any chance of testing a Sony 10-18 @ ~15mm on A7/R (where ever the vignette stops being a problem) ? I would be very interested how the native mount lens fares, even if it's designed for APS-C.
p.132 #6 · Official: Sony A7 and A7R Fullframe Mirrorless
philip_pj wrote:
It is very satisfying for me at 100%, and I want to pass this information on, and see what other people think.
+1
I often shot the D800 handheld and came to much the same conclusions as you have. 1/FL was too much a lottery, 1/ 2*FL+ delivered markedly more reliable results. This not being a huge problem for such capable sensors, upped my minimum shutter speed for Auto ISO, configuring it for 35mm which I used most, and dropped out of A mode into M mode for other focal lengths.
p.132 #7 · Official: Sony A7 and A7R Fullframe Mirrorless
RCicala wrote:
I don't know, but I speculate it may be the different ways they each have 'no' AA filter. Nikon has a two layers of lithium niobate (if I spelled that correctly) aligned at 180 degrees to cancel each other out. If I understand correctly, the A7R has none at all.
I have no idea why this might make a difference (is there an optical physicist in the house?) but it's the only thing I can think of.
Hey Roger, thanks for the test. What shutter speed was used on the A7R? I know you get inundated with requests after one of these tests but I'd love to know how well the A7R performs across various shutter speeds vs the D800E w/MLUP+timer (ie, a test integrating camera vibration into the results). Most interesting would be from 1/125 to 1/8.
Thanks Serhan, I am meaning to test it somewhat myself - I have both the 10-18 and can adapt the Nikon version of the SY. Just need to find some time for it (and motivation to get out in the snow, probably the most difficult part).
Still, the Imatest numbers would be of great interest for sure. Roger's results would certainly be less debatable than mine. And I'm trying to stay out of debates for a while.
Ok, I shot a set in my living room w/ adapted SY15 and 10-18 on Sony (set to 15) at various apertures. The Sony killed it on A7. Not sure if it's an adapter issue or, if it really just kills it that badly.
p.132 #12 · Official: Sony A7 and A7R Fullframe Mirrorless
Thanks again Roger.
Some comments on this preliminary analysis that raises more questions that will be good to see answered over time.
The 50MP is reported at f5.6 for the Nikon (1260/600) but only f2 and f2.8 for the a7r (1335/410 and 1410/440 respectively) - this is a good candidate lens in my opinion for a full comparison table - f2-f11 in full stops.
Now Zeiss' own data for the 50MP for centre and corner at infinity for 40lpmm is approx. (58/25 at f2 and 76/40 at f5.6). These seem to align quite well with Imatest data on the D800e in proportionate terms at least.
I won't go into the various opinions of both test method and 50MP lens performance at different focal distances here. It would be great to see the small aperture 50MP data on the a7r....the lens is rather weak in the corners obviously - almost all 50s are.
Tariq, I think Roger mispoke when referring to 'retrofocus' lens, meaning instead 'symmetrical' wide angle lenses.
Of course the one lens to test in the wide angle arena is the ZEF 21/2.8 Distagon, infinity data averaged across sag/tan (as used above for 50MP, sorry to have omitted to say) are (80/41 at f2, and 75/55 at f5.6) with the latter dominated by the super sag line - 65 into the very corners. All CZ data for 40lpmm.
I have the CY 21/2.8 (not quite as high in corners but better behaved overall) and it looks terrific so far on the a7r but I will do more shooting with it at smaller apertures very soon. These lenses present no problems for the a7r E mount as the max beam angle does not exceed 20 degrees, that is straight from Zeiss. Many folks here have the ZEF and might chime in also.
The Leica 50AA result does not surprise and see that numerically it does very well on the a7r in the corners in any case. For 35mm lenses we need that fabulous RX1 Sonnar! too bad...
p.132 #14 · Official: Sony A7 and A7R Fullframe Mirrorless
It was good to see some acknowledgment that adapters are not necessarily the bogeymen they might seem to be from purely empirical data, in much the same way as field curvature must be thought of as it affects physical space captured in the image.
The Sony FUD is taking hold over in DPR regarding the FE 35/2.8, which is now accused of all sorts of things, including 'concentric circles' or some such. People are really having a hard time coming to terms with the excellence of this camera, and it was surprising to see Roger so anti-alt lenses in the intro to his article - 'the idea of yet another camera body good mostly for shooting lenses on adapters wasn’t very exciting. So I planned to ignore it.'
This was always going to be a hugely significant camera(s), and clearly aimed initially at folks using 'legacy everything' lenses, E mount APS-C lenses, ZA lenses...looks like a pretty good list for Sony users of all persuasions, but the expectation from 'the establishment' is seemingly that you must release a whole raft of lenses along with the camera, or suffer derision. How hard is it to mount an adapter, what, 10 seconds? Some even provide AF and EXIF and more.
Given the wide acceptance of NEX as an alt platform I put it down to people 'needing a system' and that is about the only thing to say against the cameras. That complaint will look pretty hollow later in 2014, of course. Would users be happier if Sony had released the a7 series in late 2014 with 7-8 lenses? Not me, not by a long shot.
p.132 #15 · Official: Sony A7 and A7R Fullframe Mirrorless
As ever you make good points, Philip, except that IMHO the FE 35 shows that the benefits of a lens designed to fit A7 and A7R are significant, and advance pics tell pretty much the same story about the FE 55. Light lenses, cheap by Zeiss standards, yet great results.
My guess is that Zeiss and Sony Zeiss will rule the A7 and A7R lens space once they release a full lineup. But, as written, it is only a guess.
p.132 #16 · Official: Sony A7 and A7R Fullframe Mirrorless
It's nice to see imatest evaluation match up with results we've been seeing. It wasn't a mirage that we've seen pretty much every lens look better on the A7r, at least in the centre.
That the tiny, light, native FE35 is churning out such high performance is hopefully a good sign that Philippe's guess about future native lens prospects is a good one.
p.132 #17 · Official: Sony A7 and A7R Fullframe Mirrorless
Are Imatest results only reliable for very close distances? That is, is there any way to tell how a lens will perform at longer distances/ infinity based on Imatest?
p.132 #18 · Official: Sony A7 and A7R Fullframe Mirrorless
mco_970 wrote:
Thanks Serhan, I am meaning to test it somewhat myself - I have both the 10-18 and can adapt the Nikon version of the SY. Just need to find some time for it (and motivation to get out in the snow, probably the most difficult part).
Still, the Imatest numbers would be of great interest for sure. Roger's results would certainly be less debatable than mine. And I'm trying to stay out of debates for a while.
Ok, I shot a set in my living room w/ adapted SY15 and 10-18 on Sony (set to 15) at various apertures. The Sony killed it on A7. Not sure if it's an adapter issue or, if it really just kills it that badly. ...Show more →
I just went outside to go get some coffee and shot with this lens on my A7R. It's quite bad. The shading isn't as bad as I have seen some tests on the internet, but the smearing is very bad in the edges and corners. I was quite surprise to find most of the shading are gone in the 13-15mm range, but I wouldn't call the images usable. This is the lens that have me torn over selling my NEX-7. It's not like it's a world beater. It's just that for the size, it's quite spectacular on APS-C. I can only imagine how much larger the FF version will be. My current thinking is to keep the NEX-7 to use with this lens, and sell every other APS-C E lenses.
p.132 #19 · Official: Sony A7 and A7R Fullframe Mirrorless
RCicala wrote:
I don't know, but I speculate it may be the different ways they each have 'no' AA filter. Nikon has a two layers of lithium niobate (if I spelled that correctly) aligned at 180 degrees to cancel each other out. If I understand correctly, the A7R has none at all.
I have no idea why this might make a difference (is there an optical physicist in the house?) but it's the only thing I can think of.
Rather than the AA filter I wonder if it might be the offset micro prisms. Even the 35mm EF lens still had only 1/2 the res at the corners.
p.132 #20 · Official: Sony A7 and A7R Fullframe Mirrorless
Does the A7R really have no opposed AA-filters, like the D800? I have heard both.
With all the smearing and corner problems, I am beginning to wonder if the filter pack is quite thick (which it might be, considering the prices of these cameras are so low).
Very interesting perspective!! 