BastianK wrote:
The VM 21mm 3.5 Color-Skopar is a nice extremely compact and affordable 21mm lens,
but the VM 21mm 1.4 Nokton is almost a better performer at f/1.4 than the 3.5 at any aperture.
Cosina is nowadays primarily a fast to super-fast lens company, with 13 of their listed 29 VM lenses being faster than f2. They know their customers well, I am sure, hence: 'Enjoy bokeh with a super wide-angle'. The 21/1.4 glass specification is two asph elements and three APD elements, inside a massive 13 elements, their most complex (non-macro) full-frame lens, along with another 21mm, the 21/1.8 Ultron.
Cosina wanted users of slow lenses (we do exist) to make do with a single asph and a single APD element in the fine (for what I do) 21/3.5 Color-Skopar. So 'slow equals less performance' describes their lens range as well, we may surmise. I count that as a missed opportunity. Here is why:
Leica took a very different direction in 2011 with its production of the jewel-like SEM 21/3.4. With two asph surfaces and four APD elements, it lavished attention on its new f3.4 super wide-angle, and made that happen inside an eight element design.
It displays 2023 levels of sheer performance and adds beautiful colour, ultra low astigmatism, low curvature, 1.5% distortion levels, and the best managed outer frames of all of the stills 21s I've inspected. It is as good at f3.4 as it is at f5.6.
At 280 grams, it is just half the lens the 21/1.4 is. At 560 grams, that latter CV one would be the heaviest in many a bag of photographers like me, and that is why it would never make a single image for my non-casual needs.
Priorities matter, as does your choice and presentation of subject material, and your locations, and how you get there. To arrive at the images you need, all these are critical inputs to realised 'lens performance' in the real world. I'd pay double the price of the 21/3.5 if Cosina had the wisdom and interest that Leica showed back in 2011. Lenses simply have to be fit for purpose, and those purposes vary widely.
BastianK wrote:
The VM 21mm 3.5 Color-Skopar is a nice extremely compact and affordable 21mm lens,
but the VM 21mm 1.4 Nokton is almost a better performer at f/1.4 than the 3.5 at any aperture.
At infinity distance, the CV 21/1.4 Nokton actually performs better than the mighty Leica 21/3.4 SEM starting at f/4 at the corners. I tested a few copies to confirm this. The gap is subtle but if you're really pixel-peeping, you'll notice it.
However, when it comes to overall resolution across the entire frame and compactness, the Leica comes out on top.
Fred Miranda wrote:
Great images! Another vote for the 21/3.4 SEM. Sharp across the field with no dip anywhere. Great micro-contrast and colors from wide open.
Having said that, the CV 21/1.4 Nokton is another gem....a faster one.
Fred,
I thought this 21/1.4 Nokton was the lens you said was not consistent across the frame. Am I missing something?
stgrove wrote:
Was there a reason you were debating about selling your CV 21/1.4?
I had the Loxia 21 several times before, didn't really like how it operates. I have had the CV 21 f1.4 for several years, love it except the weight. I don't recall I have ever shot at f1.4 so I am carrying the extra glass for nothing. I was going to sell the CV 21 after I re-acquired the Loxia, but the used price for the CV 21 is just ridiculously low ($500ish?). I may not bother to sell it. In terms of image quality, for me, either one is superb but I don't pixel peep.
Fred Miranda wrote:
Only at wide apertures due to wave field curvature. At smaller apertures, it's one of the sharpest 21mm lenses out there.
Thanks. So at 1.4 it has wave field curvature. When I buy a 1.4 I intend to use it mostly at 1.4 so it is a no go for me it seems.
stgrove wrote:
Thanks. So at 1.4 it has wave field curvature. When I buy a 1.4 I intend to use it mostly at 1.4 so it is a no go for me it seems.
Most 21mm lenses show some kind of field curvature when wide open. Faster lenses, such as the Nokton, tend to have more noticeable curvature. Even a top-notch lens like the Loxia 21 exhibits strong field curvature even at f/2.8.
At around f/4, usually the curvature is masked by depth of field and in the case of the Nokton, it's super across the entire image field.
You'd only see the ill-effect of FC when capturing something flat across the frame, like in astrophotography for example.
Douglas L wrote:
I had the Loxia 21 several times before, didn't really like how it operates. I have had the CV 21 f1.4 for several years, love it except the weight. I don't recall I have ever shot at f1.4 so I am carrying the extra glass for nothing. I was going to sell the CV 21 after I re-acquired the Loxia, but the used price for the CV 21 is just ridiculously low ($500ish?). I may not bother to sell it. In terms of image quality, for me, either one is superb but I don't pixel peep.
If you can live without a super speed 21, the 21 SEM is about as perfect and corrected a 21mm lenses that exists today. Arguably the best overall as Fred mentions above. Do you really, really need a super fast 21? It's not a focal length I'm all that driven to isolate subjects with; the 28 Summiliux serves that purpose well. But as always, YMMV, especially if astrophotography is your thing.
As for the CV 21 resale value, a new one is $850 at CameraQuest, so $500 is a pretty solid price.
j.liam wrote:
If you can live without a super speed 21, the 21 SEM is about as perfect and corrected a 21mm lenses that exists today. Arguably the best overall as Fred mentions above. Do you really, really need a super fast 21? It's not a focal length I'm all that driven to isolate subjects with; the 28 Summiliux serves that purpose well. But as always, YMMV, especially if astrophotography is your thing.
As for the CV 21 resale value, a new one is $850 at CameraQuest, so $500 is a pretty solid price.
Thanks for the info. Isn’t the SEM Leica M mount? I don’t have a Leica camera, only the lowly Sony.
Fred Miranda wrote:
Most 21mm lenses show some kind of field curvature when wide open. Faster lenses, such as the Nokton, tend to have more noticeable curvature. Even a top-notch lens like the Loxia 21 exhibits strong field curvature even at f/2.8.
At around f/4, usually the curvature is masked by depth of field and in the case of the Nokton, it's super across the entire image field.
You'd only see the ill-effect of FC when capturing something flat across the frame, like in astrophotography for example.
I often find the field curvature to be an asset with lenses such as the Loxia 21. This is most beneficial for scenes featuring middle/distant central subject area, and closer details on the sides/corners of the frame, and good through about f/5.6, where it evens out to more flat field as you said (no noticeable field curvature after about f/4). As you said, the field curvature is not an issue unless shooting flat subjects at wider aperture, and how often does that happen in nature, or even architecture?
I've often thought of getting the CV 21/1.4, but since I don't need f/1.4 for precise focusing or subjects with shallow depth of field, the Loxia 21 stays my more practical alternative. But I'm always curious. . . so, never say "never", right?
Gunzorro wrote:
I often find the field curvature to be an asset with lenses such as the Loxia 21. This is most beneficial for scenes featuring middle/distant central subject area, and closer details on the sides/corners of the frame, and good through about f/5.6, where it evens out to more flat field as you said (no noticeable field curvature after about f/4). As you said, the field curvature is not an issue unless shooting flat subjects at wider aperture, and how often does that happen in nature, or even architecture?
I've often thought of getting the CV 21/1.4, but since I don't need f/1.4 for precise focusing or subjects with shallow depth of field, the Loxia 21 stays my more practical alternative. But I'm always curious. . . so, never say "never", right? ...Show more →
I frequently shot landscapes using the Zeiss 28/2 ZF lens. My approach involved focusing at infinity and achieving sharpness in the foreground as well by shooting at f/4. This is a great example of understanding the lens curvature and applying that knowledge in the field.
Fred Miranda wrote:
I frequently shot landscapes using the Zeiss 28/2 ZF lens. My approach involved focusing at infinity and achieving sharpness in the foreground as well by shooting at f/4. This is a great example of understanding the lens curvature and applying that knowledge in the field.
Another of my favorite lenses: Zeiss ZE 28/2!
Yes, understanding such issues for specific lenses can make them a big asset compared to "flat field" in landscape and architectural applications for adequate DOF at wider apertures, such as f/4.0-8.0.
Douglas L wrote:
Thanks for the info. Isn’t the SEM Leica M mount? I don’t have a Leica camera, only the lowly Sony.
Not so lowly if you get the Kolari modifications.
Fred Miranda wrote:
I frequently shot landscapes using the Zeiss 28/2 ZF lens. My approach involved focusing at infinity and achieving sharpness in the foreground as well by shooting at f/4. This is a great example of understanding the lens curvature and applying that knowledge in the field.
The ZM 2,8/25 is another with a pretty dramatic curvature of field that if understood, can be used creatively. None of the Zeiss SLR wide-angle lenses had a flat field. Additionally, the OG NOCT Nikkor is another with the same feature.
Since this old thread is still active... I have to ask.... How are people feeling about the CV21 f1.4 vs the Sony 20mm f1.8?
I have the Sony 20G and the Loxia 25mm that I keep just for sunstars and color, but I sometimes wonder if I would be happier with the CV 21mm f1.4 to replace both. I current use 20mm G for astro and just upgraded my 16-15GM to the version II.
Is this just a GAS attack for me or is there something special about the CV 21mm F1.4?
