This is a very interesting time in camera technology, and by turn, in the testing of camera technology. Moore's law seems to be in full effect for megapixel counts, even though Moore's progress has been slowing down a bit in the computing world. 

This has been a bit of an issue for us when it comes to the lenses we use on the studio scene test. Resolutions are going up, and some of our tried and true glass is having trouble meeting the demands. The first to fall behind was the (otherwise excellent) Olympus 45mm F1.8. It never had a problem with the "sweet sixteen" Micro Four Thirds resolution standard, but shots on the pixel-shift high resolution mode of the E-M5 II left much sharpness to be desired. That was remedied with the borderline ridiculous $1,600 lens made from what has to be glass from the fires of Mordor; the Panasonic 42.5mm F1.2 Nocticron. That much bread for a Micro Four Thirds lens goes against everything (we think) the system stands for, which is why the Olympus 45mm F1.8 still serves as our studio lens.

Our lens choices are based on a number of factors. We try to get the highest quality glass we can within a certain focal length range, for a real-world price. We also try to stick with the same lens for any given system to rule out variances in transmission and aperture diameter, so that noise comparisons in our studio scene are rigorous and valid. Finally, different systems have different availability, which is why we are still using the 16-50mm F2-2.8 zoom on Samsung cameras, for example. 

Another lens to possibly buckle under pressure is the now classic Canon EF 85mm F1.8. Many questions have been raised over the use of this glass on the 5DS and 5DS R, but it does exactly what we want. It resolves remarkably well on the 'highest resolution full-frame sensor in the world' and doesn't cost a kidney and a lung just to rent for an afternoon. Heck, at F5.6, it does as well as the way more expensive Nikon 85mm F1.4G. Performance sans price, that's what we like to see. 

The Canon EOS 5DS R, home to more than 50 million pixels of sensor resolution.

In other words, when it comes to ILCs, the lens needs to be more than just the best an infinite amount of money can buy. It has to be accessible for real-world users and not a fussy piece of "oh look what we can do" that was made more for test charts, which brings me to the Zeiss Otus. That IS an "oh look what we can do" lens that was developed as more of a technical exercise than a piece of kit that would actually go on sale. However, demand for perfection in this industry is so high that Zeiss had many requests for copies of their first Otus, the 55 F1.4, and so they went ahead and made it. 

And now, for us, you, and everyone else, here it is. We proudly present to you the Zeiss 85mm F1.4 Otus, one of the nicest (and heaviest) things Sam, our tester, has ever held, mounted on the 5DS R and the Nikon D810 for your peeping pleasure.

And oh what a lens it is. 

Well... hang on a minute. In the scene's text the last line isn't exactly more readable on the Otus than either system's normal studio lens. By the way, you'll note we knocked the lens on the D810 back down to the very affordable, yet excellent Nikkor 85mm F1.8G, since we received some complaints about it being unfair to compare the 5DS with the 85/1.8 but the D810 with the 85/1.4 (nevermind the fact that it followed our 'sharpest 85mm of the system' rule). If anything, the shots with the Otus lenses are just aliasing more aggressively, and there may be slightly more sharpness, although the placebo 'it costs more' effect could be in play. There certainly isn't a level of resolution beyond what either of the 'regular' 85mm lenses pull from the studio scene. 

The paint tubes up on the left are one of the places where the EF 85 does fall behind a bit. And, to be honest, The Beatles are definitely looking sharper than usual. 

Unless you're really fishing for it, the differences between the Otus and our two studio lenses are practically negligible at this aperture setting. There's more sharpness and microcontrast, but resolution is not vastly improved, mainly because the Canon and Nikon 85/1.8 primes are just so good. The center target is where the real differences start to show. The hard contrast of the edges show the two 'lesser' lenses to have magenta aberrations around the edges of the target when stopped down.

The Otus has no time for such plebeian matters. Especially when shot wide open. Yes, it does aberrate a bit, but this is F1.4. Compared to the other two, the price difference really starts to show. Both Canon and Nikon F1.8 primes fall behind with respect to purple fringing, with the Canon EF also dropping considerably in sharpness while the Nikkor maintains impressive sharpness despite the fringing (which can, to varying degrees of success, be removed in post-processing of Raw files).

Stop the 1.8's back down, and take a look around the scene on the F1.4 Otus shots. At many flatter places (because DOF is now a factor) it does nearly as well as the 85mm F1.8 lenses. That is impressive. The Nikon with the Otus does show a bit more softness at F1.4 near the corners, a great reminder of the reality of manufacturing tolerances of mounts and alignment of optical elements. 

This test wasn't easy. The Otus is a manual focus lens only, and it required many shots and a delicate hand (which isn't always available after a tall can of Red Bull) to get focus just right at F1.4, and then again at F5.6. Yes, this cost-is-no-object lens does have focus shift. A shot focused in live view at F5.6 is not going to be sharp at F1.4, and a shot focused at F1.4 is not necessarily going to be sharp at F5.6. 

So there you have it, the Canon and Nikon 85mm F1.8 lenses are quite alright at F5.6, all things considered, but the Otus can keep up with them at F1.4, which is a mighty feat. For those that can't stomach the price but need the resolution, there are other usable, more practical options.