philip_pj wrote:
Fred posted comments, maybe comparisons with the Loxia 21mm in his review of the 21/3.5, perhaps also did this for the 21/1.4. Each newcomer has to face the existing top dog, kind of. See page 1 of each new appearing lens.
I was looking for a direct exact same image comparison between the 3 at infinity and much closer in distances.
Perhaps I will get the 21/1.4 as an X-mas present to myself and do the 3-way test (and post).
Just need some consistent good weather.
One may ask why the interest in the 21/1.4 if I already have the CV/3.5 and the Lox, well, sometimes I don't want that everything in focus look in a close-in wide shot, especially for candids and many times those candid wide angle shots are in low light. The CV 21/1.4 seems more than sharp enough wide open across most of the frame to do this.
justincrabtree wrote:
I was wondering why you sold it. I might still go for it, but I have a Loxia 35 arriving soon and want to compare it with my CV 40 for landscapes before deciding on a 21. Images on Flickr tend to have a little more magic with the Loxias (21 & 35) from what I can tell, but I don't favor their colors as much as CV. The CV 40 is perfection OOC with its color at wider apertures, but I haven't given it a go stopped down yet. Deep down I want all CV's to keep the kit uniform and to satisfy my OCD, but alas. How are you liking the CV 65 for landscapes? It's the other lens I've been wanting to try, so in a perfect world it'd be CV21/1.4, CV40, CV65, 100-400 GM. ...Show more →
The first thing I did when I got the A7R4 was to test the CV 21/1.4 on it. The sharpness discrepancy between center and mid-field was way more noticeable compared to the A7R3's. (Due to wavy FC)
Personally I prefer having strong center and mid-field instead of strong center and corners.
I've compare great copies of the Loxia 35 and CV 40/1.2 at infinity and it's pretty much at wash in terms of resolution/contrast at about f/7.1 (optimal for both lenses). The Voigtlander has stronger mid-field at wider apertures and the Loxia has slight better corners. I still own both. The Loxia 35/2 also has wavy FC.
justincrabtree wrote:
The 21/3.5 is tempting for sure, especially for the price and weight (for longer hikes).
I found that the CV 21/3.5 + 60MP not to be a great combination.
The mid-field dip is very noticeable imo. In resized images for the web, it's not very apparent but if you are thinking of printing big, it may bother you depending on the image.
On this lens, the culprit is not field curvature. It's a dip in resolution towards the mid-field (by design). It improves by f/8 but it's never strong. I would still recommend the Loxia 21 instead. If you want flat-field, there is nothing better than the 24/1.4 GM.
Fred Miranda wrote:
If I didn't already own the FE 24/1.4 GM, I would have kept it. For landscapes, I prefer the smaller and lighter Loxia 21/2.8.
Both lenses have very similar resolution and micro-contrast. Both have some field curvature but I prefer the Zeiss's FC since it's inwards instead of wavy at infinity.
Thank you, very interesting and unexpected after reading your review.
Fred Miranda wrote:
Here is how both lenses perform at the extreme corners when focused on that area instead. The Loxia performed better while the Voigtlander did not improve showing it has negligible field curvature.
….
Mid-field at f/4: CV 21/1.4 pulls slightly ahead
In this case, I think it would be great if you could adjust your review.
I understood your review as if the Voigtlander 21mm f1.4 was particularly more recommendable than the Loxia because of its flat field and that it was minimally sharper across the entire image.
Because you now seem to think that the Loxia is better for landscapes…
Fred Miranda wrote:
The first thing I did when I got the A7R4 was to test the CV 21/1.4 on it. The sharpness discrepancy between center and mid-field was way more noticeable compared to the A7R3's. (Due to wavy FC)
Personally I prefer having strong center and mid-field instead of strong center and corners.
HelBen85 wrote:
Thank you, very interesting and unexpected after reading your review.
In this case, I think it would be great if you could adjust your review.
I understood your review as if the Voigtlander 21mm f1.4 was particularly more recommendable than the Loxia because of its flat field and that it was minimally sharper across the entire image.
Because you now seem to think that the Loxia is better for landscapes…
Because your pictures (review) do not match this conclusion and there is not one single picture showing the effect of this wavy field curvature. In the review you mentioned a negligible field curvature (quote FM Review: "Mid-field at f/4: CV 21/1.4 pulls slightly ahead" .... "The Loxia performed better while the Voigtlander did not improve showing it has negligible field curvature"...) and now it should bother you more than with the Zeiss.
Your review says that at f4 the Voigtländer pulls ahead at mid zone. How does that match with the (new?) conclusion?
By the way, your (old?) conclusion was also misunderstood by others, Phillip Reeve, for example, understood your review in the following way:
Quote: "Zeiss Loxia 2.8 / 21: Based on Fred Miranda’s tests the Loxia shows more field curvature than the Voigtlander because of which the Voigtlander can be sharper in flat scenes."
It's your forum, so it's up to you... I think your test results are among the best that can be found on the internet and I take them quite seriously, but I believe that in this case you yourself no longer consider your test results (comparison images) to be correct. Your words now sound like there is a mid zone dip like the 21mm f3.5 has it, but not quite as strong.
That would actually be something that might interest buyers when studying your review.
The Voigtlander 21/1.4 has a slight wavy field curvature
The Loxia 21/2.8 has inwards field curvature.
I wrote that the CV 21/1.4 has negligible FC towards the corners since the curvature shape is different. This is much more noticeable on the A7R4 since the center gets even stronger (more resolution) and the area suffering from the FC effect does not improve (appear even worse with more pixels) which makes the discrepancy between sharp and soft (OOF) more evident.
The field curvature is more evident wide open and I compared it to the Loxia starting at f/2.8 where FC was masked by DOF. (2 stops)
Your words now sound like there is a mid zone dip like the 21mm f3.5 has it, but not quite as strong.
Two different things here. The CV 21/3.5 has a resolution dip towards the mid-field area (by design). This is not due to field curvature as focusing on mid-field does not improve this area.
On the other hand, The CV 21/1.4 Nokton has a slight wavy FC shape which is more prominent with the new high MP sensor.
pdmphoto wrote:
Maybe tbe difference from your past result has to do with the A7r4? 42mp is more than sufficient resolution to show field curvature.
It was also visible on the A7R3 when wide open. The A7R4 just makes FC even more apparent.
Here is the link comparing it to the Sony 24/1.4 GM @f/1.4. Look at the mid-field crops wide open: https://www.fredmiranda.com/forum/topic/1603441/1#14903463
The FE 24/1.4 GM is the most flat field lens in comparison.
Fred Miranda wrote 'Both have some field curvature but I prefer the Zeiss's FC since it's inwards instead of wavy at infinity'.
I think this is the comment that is causing the confusion Fred. On the A7rIII, by f2.8, the slight mid-field wavy field curvature of the Voight 21mm f1.4 is masked by DOF, so it doesn't make sense to prefer the Loxia 21mm f2.8 for its inwards field curvature, because at f2.8 the Voigt is effectively flat field, and therefore better. This just leaves the size/weight advantage for the Loxia, which you mention.
On your original comparison between the Voigt and Loxia 21mm here https://www.fredmiranda.com/forum/topic/1603441/0#14903019 you conclude that when focused on the center, the mid-field of both lenses at f2.8 shows 'similar performance', with the Voigt 'pulling slightly ahead' at f4.
So you now seem to be suggesting that the higher resolution of the A7rIV, which effectively reduces the apparent DOF, is not masking the Voigt's field curvature at f2.8, therefore making the Loxia preferable when shooting at 2.8?
However, if the Voigt is sharper mid-field at f4 than the Loxia, on your original A7rIII tests, it surely can't become less sharp (in an absolute sense) at mid-field f4 on the A7rIV. As you say, its just less sharp relative to the now-even-sharper center. I suspect the Voigt will be the sharper lens at mid-field on the A7rIV when shot at f4, leaving the only advantage for the Loxia (from a field curvature perspective), at f2.8.
Dec 22, 2019 at 08:43 AM
Steve Spencer Online • • • • • • • Upload & Sell: On
I think this is the comment that is causing the confusion Fred. On the A7rIII, by f2.8, the slight mid-field wavy field curvature of the Voight 21mm f1.4 is masked by DOF, so it doesn't make sense to prefer the Loxia 21mm f2.8 for its inwards field curvature, because at f2.8 the Voigt is effectively flat field, and therefore better. This just leaves the size/weight advantage for the Loxia, which you mention.
On your original comparison between the Voigt and Loxia 21mm here https://www.fredmiranda.com/forum/topic/1603441/0#14903019 you conclude that when focused on the center, the mid-field of both lenses at f2.8 shows 'similar performance', with the Voigt 'pulling slightly ahead' at f4.
So you now seem to be suggesting that the higher resolution of the A7rIV, which effectively reduces the apparent DOF, is not masking the Voigt's field curvature at f2.8, therefore making the Loxia preferable when shooting at 2.8?
However, if the Voigt is sharper mid-field at f4 than the Loxia, on your original A7rIII tests, it surely can't become less sharp (in an absolute sense) at mid-field f4 on the A7rIV. As you say, its just less sharp relative to the now-even-sharper center. I suspect the Voigt will be the sharper lens at mid-field on the A7rIV when shot at f4, leaving the only advantage for the Loxia (from a field curvature perspective), at f2.8....Show more →
I think what you are missing in this analysis is that with the A7r IV focus become more finicky. The Voigt 21 f/1.4 has wavy field curvature at every aperture whether it is masked by DOF or not. If it is masked by DOF, then the point with good focus is still smaller and if you get focus slightly off, then it won't be masked any longer. So, shooting with the Voigt 21 f/1.4 will be trickier because you will have less leeway to be off just a bit in focus. In contrast with the Loxia 21 f/2.8 if you are off a bit then it will only be in the corners and far away from the center, so it won't be as noticeable and in some people's shooting (typically mine) it is less likely to contain important elements of the composition. All that said, both lenses are excellent. Both will produce fantastic landscapes. Personally, I have the Voigt 21 f/1.4. I might pick up the Loxia 21 f/2.8 again, however, for when I want a lighter kit. That said I might get the Voigt 21 f/3.5 for that. We are really really fortunate to have all three of these excellent lenses available.
I think what you are missing in this analysis is that with the A7r IV focus become more finicky. The Voigt 21 f/1.4 has wavy field curvature at every aperture whether it is masked by DOF or not. If it is masked by DOF, then the point with good focus is still smaller and if you get focus slightly off, then it won't be masked any longer. So, shooting with the Voigt 21 f/1.4 will be trickier because you will have less leeway to be off just a bit in focus. In contrast with the Loxia 21 f/2.8 if you are off a bit then it will only be in the corners and far away from the center, so it won't be as noticeable and in some people's shooting (typically mine) it is less likely to contain important elements of the composition. All that said, both lenses are excellent. Both will produce fantastic landscapes. Personally, I have the Voigt 21 f/1.4. I might pick up the Loxia 21 f/2.8 again, however, for when I want a lighter kit. That said I might get the Voigt 21 f/3.5 for that. We are really really fortunate to have all three of these excellent lenses available....Show more →
Thanks for your reply Steve - that does make it clearer what Fred's talking about, although you are introducing another variable into the argument (i.e. user error). Of course there only ever is one plane that is actually in focus; how far in to the defocus MTF region either side of that you still consider acceptably sharp depends on a whole range of things (print magnification, your eyesight, personal preferences etc). My point was there is no change in sharpness at the mid-field far and near DOF limits with the Voigt whether you are shooting A7rIII or A7rIV: as I said, the only thing that changes with the A7rIV is the apparent DOF, because the image plane has become sharper, relative to the adjacent defocus MTF region.
So as Fred points out, the Viogt 21 f3.5 would not be a good choice for you to re-buy, as it has a real mid-field resolution dip caused by residual optical aberrations, not field curvature, which is even more noticeable with the A7rIV. The Voigt 21 f1.4 has no mid-field resolution dip - the sharpest plane of focus is just forward (i.e closer to the photographer) at this point. If you routinely shoot infinity scenes at f2.8, yes, I can see why the Loxia might be better. In more typical deep-DOF shots taken around the hyperfocal distance at F5.6-11, the slight W-shape of the Voigt 21 f1.4's field curvature becomes less relevant.
..I don`t see what you guys see - for me it is an fantastic lens. I use it mainly for landscape, so maybe for that reason the Loxia would be the right choice - but I have it and I`m happy with it.
Fred Miranda wrote:
The weather is not great but here are crops showing how more evident the wavy field curvature is on the A7R IV when shooting wide open:
(Not corrected for vignetting / distortion). Focused at center.
Fred, do you still have the shots taken at f2.8 and f4 on your computer - I'd be interested to see what happens to the mid-field field curvature on the A7rIV?
and do the 3-way test (and post).
