p.1 #1 · Wide angle native prime on APSC mirrorless
I was browsing through photozone's test result and something struck me: I cannot find a native wide angle prime on APSC mirrorless with a decent wide open corner performance. Not from Samsung, not from Sony, and not from Fuji. Compared that with m4/3's two prime and two zoom, I wonder if there is some inherent limitation with ~20mm flange distance+APSC sensor size? Maybe the optimal flange distance should be around 30mm if one scale from m4/3's dimension?
And why is a retrofocus design needed for E 24/1.8, which is not really wide anyway? Gotta wait for Sony's wide zoom and Fuji's 14mm to confirm I guess.
p.1 #2 · Wide angle native prime on APSC mirrorless
No, there's just a lack of high-end native wide-angle primes, to be exact there are none, the closest one being the Fuji 18/2, which is optimized for centre sharpness rather than cross-frame performance to deliver a street-shooting lens at a reasonable cost, the 16's from Samsung and Sony are both lower end lenses that need stopping down.
Note that only one of the two m43 wide primes has good wide-open corner performance (the 14/2.5 lags the Sigma 19 at all apertures while delivering a comparable field of view). If you compare performance per dollar, APS-C wins, with all of the wide opens offering more bang per dollar than the m43 options (which are expensive aside from the 14/2.5 and that isn't any better than the similar-priced APS-C options).
As to the ZA E 24, it needs a retrofocus design to keep the exit pupil away from the sensor. The wideness of the lens is irrelevant, the physical distance between the sensor and exit pupil is what matters.
p.1 #4 · Wide angle native prime on APSC mirrorless
The sigma is pretty cool, but it's not exactly wide on m4/3 and should be compared to 20/1.7? It seem to be the best wideish prime on APSC mirrorless though.
Does a 35mm FOV eq lens need to be retrofocus? The Biogons seem to be fine on M9, but then there are microlenses... um...
p.1 #6 · Wide angle native prime on APSC mirrorless
aleksanderpolo wrote:
Does a 35mm FOV eq lens need to be retrofocus? The Biogons seem to be fine on M9, but then there are microlenses... um...
24mm on APS-C (~35mm equiv.) shouldn't need to be a retrofocus design for a mirrorless camera. If Sony/Zeiss had used a symmetrical design it might have caused too much color shift on the NEX-7 though.
p.1 #7 · Wide angle native prime on APSC mirrorless
This is why I'm on full frame for the forseeable future, as much as I'd love to go to a smaller kit . The 5D + OM wide angles is superb and still very portable.
p.1 #8 · Wide angle native prime on APSC mirrorless
aleksanderpolo wrote:
The sigma is pretty cool, but it's not exactly wide on m4/3 and should be compared to 20/1.7? It seem to be the best wideish prime on APSC mirrorless though.
Does a 35mm FOV eq lens need to be retrofocus? The Biogons seem to be fine on M9, but then there are microlenses... um...
I'm comparing the Sigma 19 on APS-C to the Panasonic 14/2.5 on m43, they're both around 28mm-e then.
p.1 #9 · Wide angle native prime on APSC mirrorless
AhamB wrote:
24mm on APS-C (~35mm equiv.) shouldn't need to be a retrofocus design for a mirrorless camera. If Sony/Zeiss had used a symmetrical design it might have caused too much color shift on the NEX-7 though.
It does need to be a retrofocus design on mirrorless at that focal length unless the sensor has a microlens array with compensation. 24/25mm is where problems really start hitting with most symmetric lenses even on the NEX-5N (which has shown issues with some 25mm lenses), the NEX-7's much more demanding sensor design pretty much drove the size increase for the ZA E 24, the original prototypes shown were around 1/3 shorter than the lens that shipped.
p.1 #10 · Wide angle native prime on APSC mirrorless
joxang wrote:
This is why I'm on full frame for the forseeable future, as much as I'd love to go to a smaller kit . The 5D + OM wide angles is superb and still very portable.
Even with the OM lenses, the 5D isn't exactly in the same boat for portability as mirrorless. My NEX-7 walkaround kit is lower volume than a 5D body alone (NEX-7 + ZA E 24/1.8 + Nikkor-S.C 5cm f1.4 LTM with adapter), if I go with my one-lens kit (NEX-7+ CV 35/2.5 LTM) it's about half the volume of the 5D body.
p.1 #11 · Wide angle native prime on APSC mirrorless
This is more of an APS problem than an NEX problem. The best APS wides are large, heavily retrofocal zooms -- and even most of those are less than spectacular at wide stops. Compare the 16/2.8 with the Nikon or Tokina 12-24/4 (or the Sigma 10-20) at the same focal length and f-stop, and there are more similarities than differences. The 11-16 Tokina is a little better, and I've seen good samples from the Sigma 8-16, which may be the best of the bunch. But for the most part, super wide on current APS sensors is tough to achieve in a reasonably compact design.
In fact, the 16/2.8 performs pretty comparably to legacy wide SLR primes on FX, too. The Nikon 24/2.8 is no better. You have to get into the premium (and heavy) zooms and the Zeiss primes to really achieve exceptional image quality with a full frame DSLR.
p.1 #12 · Wide angle native prime on APSC mirrorless
Its not that hard to design this stuff. For Leica M, there are excellent wide-angles, just NEX and NX systems are sorta lacking.
I guess its due fact that 1) Sony doesnt really care about their NEX 2) Samsung wants to keep package small (most are pancakes, exception is only huge 85mm f1.4).
So lets hope Samyang and Sigma will make something.
p.1 #14 · Wide angle native prime on APSC mirrorless
But then what about the Sigma 19? Do you know if it is retrofocus or not? And how big is it compared with the E24 (I have not handled either)? But I guess it is not fair comparing a 1.8 with a 2.8...
mawz wrote:
It does need to be a retrofocus design on mirrorless at that focal length unless the sensor has a microlens array with compensation. 24/25mm is where problems really start hitting with most symmetric lenses even on the NEX-5N (which has shown issues with some 25mm lenses), the NEX-7's much more demanding sensor design pretty much drove the size increase for the ZA E 24, the original prototypes shown were around 1/3 shorter than the lens that shipped.
p.1 #15 · Wide angle native prime on APSC mirrorless
Mescalamba wrote:
Its not that hard to design this stuff. For Leica M, there are excellent wide-angles, just NEX and NX systems are sorta lacking.
I guess its due fact that 1) Sony doesnt really care about their NEX 2) Samsung wants to keep package small (most are pancakes, exception is only huge 85mm f1.4).
So lets hope Samyang and Sigma will make something.
It is fairly hard to design these lenses. There's a good reason why those M lenses are the prices they are, and getting the older M wides to perform well on digital is a major reason why the M9 is as expensive as it is, as Leica had to both get their sensor customized to improve the corner performance of their wides and also do fairly extensive software corrections as well, which is the reason for 6-bit coding as well as the existence of CornerFix, this is also a major issue in the MF digital world. Symmetric wides and even retrofocus wides with an exit pupil near the sensor are simply difficult to get to work well on digital.
Sony is pretty damned slow at rolling out new lens designs. They have the same issue in A mount as in E mount. In fact E mount has it better, Sony has no good APS-C wide lenses in A mount, only the two good normal zooms that go to 16mm, E mount at least has a decent option in terms of a pure wide in the 16/2.8, the A mount 11-18 is a dog, all the real options are 3rd party. Only Pentax offers a good selection of APS-C wides, but at least both Nikon and Canon do offer at least one good zoom.
p.1 #16 · Wide angle native prime on APSC mirrorless
aleksanderpolo wrote:
But then what about the Sigma 19? Do you know if it is retrofocus or not? And how big is it compared with the E24 (I have not handled either)? But I guess it is not fair comparing a 1.8 with a 2.8...
It's retrofocus, but with an exit pupil closer to the sensor than the ZA E 24. The lens is a little more than half the length of the ZA E 24/1.8. Sony overcompensated a bit with the ZA E 24 design and it's probably more retrofocus than it needs to be.
p.1 #17 · Wide angle native prime on APSC mirrorless
Best solution I've found is a CV 15/4.5 on the Ricoh GXR. And it's native mount I haven't gotten to use a ZF 21/2.8 on my D700, but I do prefer the GXR/CV15 output to the D700/CV20 output at base ISO, all things considered.
. The 5D + OM wide angles is superb and still very portable. 
I haven't gotten to use a ZF 21/2.8 on my D700, but I do prefer the GXR/CV15 output to the D700/CV20 output at base ISO, all things considered.