Leica SL + 50mm f/1.4 Summilux-M ASPH vs 50mm f/1.4 Summilux-R

It's no secret that I've never been a fan of the Leica 50mm f/1.4 Summilux-M. I know this will not bode well for me to say that, but I've always felt that the 50 Lux was a compromise of a lens. It doesn't excel in any one area. It isn't the sharpest Leica 50mm lens, nor is it the fastest. It isn't the smallest, nor does it render the best bokeh either. Its only exceptional trait is being versatile, as a jack of all trade and a master of none, for a 50mm lens.

However, there is another 50mm Summilux that Leica M shooters often overlook (though to be honest, it wouldn't make sense for rangefinder photographers). Obviously, I'm referring to the R-mount version 50 Lux.

Having converted from Leica rangefinder photography to the Leica SL, the natural knee jerk inclination is to adapt M-mount glass... and in truth, there really is no reason to adapt anything other than an M-mount lens on the Leica SL. In short, M-mount lenses are wonderful on the SL.

Leica SL + 50mm f/1.4 Summilux-M, shot at ISO 160, f/1.4, 1/200s. I took this photograph by surprise.

Leica SL + 50 f/1.4 Summilux-R, shot at ISO 125, f/1.4, 1/200s. Anna did not appear amused, on the second shot.

Leica SL + 50mm f/1.4 Summilux-M, shot at ISO 320, f/2.8, 1/200s. Tying her shoe lace. Another opportunistic shot.

Leica SL + 50 f/1.4 Summilux-R, shot at ISO 200, f/2.8, 1/200s. This one I asked her to do it again for the 50 Lux-R, so she's not really tying her shoe laces here.

But remember my previous article on A Tale of Adaptation? In that article, I demonstrated just how much closer an adapted 35mm f/1.4 Summilux-R could focus versus the M-mount version. Well, it is the same for the 50mm f/1.4 Summilux-R. It can also focus a good 8 inches closer than the M-mount version.

With that slight advantage, I thought it would be worthwhile to dust off the old and often ignored 50 Lux-M and do a side by side comparison between the two.

In terms of the size difference between the two version, the R-mount version seems to be just a tad taller than the M-mount version. However, the M-mount version is significantly thinner than the more robust R-mount version, and therefore much lighter. Still, with regards to the amount of space it takes in my bag, the two are really not that different, in my somewhat inaccurate way of eye-balling size differences.

Leica SL + 50mm f/1.4 Summilux-M, shot at ISO 160, f/1.4, 1/200s. Shot at the lens' closest focusing distance.

Leica SL + 50 f/1.4 Summilux-R, shot at ISO 400, f/1.4, 1/200s. Shot at the M-mount version's closest focusing distance.

Leica SL + 50 f/1.4 Summilux-R, shot at ISO 800, f/1.4, 1/200s. Shot at the lens' closest focusing distance. There is much less distortion than on the 35mm f/1.4 Summilux-R.

The way I see it, they both take more or less the same amount of space in my bag. But what is significant to me is the difference in size between their respective adapters. The R/SL adapter is much bigger than the M/SL adapter. For size reference, please click here to my Instagram page, where I post my images of photographic gear. I know what you'll say when you see the comparison... you're probably going to say "is this blogger out of his mind"?

With regards to user experience, I am a converted M-mount shooter, so I have an inclination to feel for the lens tab. So it comes as no surprise that I prefer the M-mount version. In addition, M-mount lenses typically have the aperture ring by the front of the lens. So when an M photographer, like myself, begin to adapt an R-mount glass on the Leica SL, the M photographer would intuitively feel for the focusing ring closer to the lens mount, while feeling for the aperture ring closer to the front of the lens. It takes some time to adjust, but still rather irritating initially.

With regards to the difference in performances, it should be noted that this isn't exactly a fair comparison. The M-mount version is a newer aspherical design, and is therefore going to be sharper, especially at higher resolution. With that said, the R-mount version is still extremely sharp. But with all sharp lenses being sharp, some sharp lenses are more equal than others.

Leica SL + 50mm f/1.4 Summilux-M, shot at ISO 250, f/1.4, 1/200s.

Leica SL + 50 f/1.4 Summilux-R, shot at ISO 320, f/1.4, 1/200s.

The more appropriate comparison to do would be between the R-mount version and the pre-aspherical M-mount version. Unfortunately for me, I don't have a pre-aspherical version of the M-mount 50 Lux.

But for now, I think that for most Leica SL users, the majority has already updated to the newer version. Presumably, the more immediate interest would be to see how the current aspherical 50 Lux compares to the R-mount version - all for the benefit of having an extra 8 inches in closer focusing.

On the subject of focusing distance, I would like to mention one interesting anecdotal difference. I'm calling it an anecdotal difference, because I wasn't exactly careful in evaluating this difference, and because I left my 50 Lux-M at home, while I'm writing this on my lunch break at work.

Anyway, when I was photographing Anna, I noticed that when I shot from the same focusing distance, with Anna and I not moving, the focal distance seemed to be different, in that the size of Anna's face in the frame wasn't exactly the same. If memory serves me right, and if the sample images are an accurate indication, I am of the impression that the R-mount lens is a little tighter than the M-mount lens. This makes for image comparison a little difficult.

Leica SL + 50mm f/1.4 Summilux-M, shot at ISO 50, f/1.4, 1/200s.

Leica SL + 50 f/1.4 Summilux-R, shot at ISO 50, f/1.4, 1/200s.

Leica SL + 50mm f/1.4 Summilux-M, shot at ISO 320, f/5.6, 1/200s.

Leica SL + 50 f/1.4 Summilux-R, shot at ISO 1250, f/5.6, 1/200s.

Also noticeable is a difference in color rendering. The R-mount version appears to have slightly warmer skin tones than the M-mount aspherical version. In other words, there seems to be slightly more yellow in the R-mount version than the M-mount version. This of course assumes that the Leica SL sensor is consistent in white balance - which might not be the case. My first Leica M 240 was significantly cooler in rendering than my present Leica MP 240.

With regards to the rendering of bokeh, the aspherical 50mm Lux-M appeared to be slightly smoother than the R-mount version. But to be perfectly frank, the difference is somewhat imperceptible. In my opinion, both versions render almost identically.

As far as corner sharpness is concerned, both lens appear identical to me. As for contrast, the 50 Lux-M appear to be slightly more contrasty. As for barrel distortion - again - identical to the naked eye. Basically, in most quantifiable measure, both lenses perform almost the same, with improvements in the 50 Lux-M to be perceptible only if you examine it through high magnification - although I'm sure that the MPF charts would say otherwise.

Leica SL + 50mm f/1.4 Summilux-M, shot at ISO 4000, f/11, 1/200s.

Leica SL + 50 f/1.4 Summilux-R, shot at ISO 6400, f/11, 1/200s.

Leica SL + 50mm f/1.4 Summilux-M, shot at ISO 800, f/8, 1/160s.

Leica SL + 50 f/1.4 Summilux-R, shot at ISO 1250, f/8, 1/200s.

Leica SL + 50mm f/1.4 Summilux-M, shot at ISO 1250, f/5.6, 1/250s.

Overall, both lens performed exceedingly well. The main difference between the two lenses are as follow:

1. The 50mm f/1.4 Summilux-M ASPH is slightly sharper and slightly more contrasty than the 50mm f/1.4 Summilux-R.
2. The 50mm f/1.4 Summilux-R can focus 8 inches closer than the 50mm f/1.4 Summilux-M ASPH.
3. The 50mm f/1.4 Summilux-M ASPH is significantly smaller and lighter than the 50mm f/1.4 Summilux-R.

With that being the case, it seems that close focusing would be the only reason to pick the R-mount version over the M-mount version. But for most photographer, I doubt that the need for closer focusing would be enough to sacrifice additional sharpness and better ergonomics.

Leica SL + 50mm f/1.4 Summilux-M, shot at ISO 80, f/1.4, 1/160s.

Leica SL + 50 f/1.4 Summilux-R, shot at ISO 100, f/1.4, 1/200s.

Leica SL + 50mm f/1.4 Summilux-M, shot at ISO 6400, f/1.4, 1/250s.

Leica SL + 50 f/1.4 Summilux-R, shot at ISO 6400, f/5.6, 1/200s.

However, that is most photographer. From my perspective, I believe that the closer focusing distance makes the 50mm f/1.4 Summilux-R a worthwhile lens to have, since it does excel in something that neither the 50mm f/0.95 Noctilux-M, the APO 50mm f/2 Summicron ASPH, nor the 50mm f/2 Summicron version V could do. It focuses closer.

Given that both the 50 Lux-R and the 50 Lux-M ASPH perform more or less the same, closer focusing distance gives the 50mm f/1.4 Summilux-R a slight advantage in overall usage.

Now if only my 50mm f/1.4 Summilux-L is no longer backordered. Then we can really see which version 50 Lux is best on the Leica SL.

Below are some leftover sample images that I edited in post, which I didn't get to use in the review, given that I goofed by not having the same comparison shot done by the other lens.

Leica SL + 50mm f/1.4 Summilux-M, shot at ISO 125, f/1.4, 1/200s.

Leica SL + 50mm f/1.4 Summilux-M, shot at ISO 80, f/2.8, 1/200s.

Leica SL + 50 f/1.4 Summilux-R, shot at ISO 1000, f/4, 1/200s.

Leica SL + 50 f/1.4 Summilux-R, shot at ISO 250, f/8, 1/200s.

Leica SL + 50 f/1.4 Summilux-R, shot at ISO 160, f/11, 1/200s.

All images in this writeup have been optimize in Lightroom. None of the images have been cropped, so peek away at the corners... not that you can expand the images much. I have bandwidth considerations to think about.

One last note to mention. I am not 100% sure about the aperture of each sample image. For some reason, the Leica SL does not appear to be accurate in reading the aperture. So I'm using my best guess, based on my shooting habits. Sorry, there's nothing I can do, other than to write it down, while I'm shooting, which would be much too much to do.

I will no longer be thanking Anna at the end of each post, since she is now going to be a contributor to this site. It must be official, since Anna has been added to the ABOUT section.

***UPDATE*** Please note that the 50mm f/1.4 Summilux-R that was used for this review was the E60 version. As a Leica M photographer, I may not be as sensitive to the nuances of Leica R lenses, and have been corrected that the E60 version is somewhat more special than the previous versions.