Mirrorless Unleashed: Hands-On with the Leica SL (Typ 601)


When Leica unveiled the SL (Typ 601) Mirrorless Digital Camera, I was astounded by how many items it checked off on my dream-camera wish list. It has great low-light performance, fast autofocus, intuitive operation, and 4K video. It embraces both video and stills with vigor and offers users a larger body to contain all of this technology without compromise, something many other mirrorless models have avoided. When I got to test drive the Leica SL (Typ 601) it did deliver on many of its promises, though, unfortunately, it did fall short in some critical areas.

Form Meets Function

If the Q (Typ 123) was any indication, Leica’s new digital era was going to focus on producing technology-loaded cameras that aren’t worried about following the normal conventions of the industry. The Q did this by packing a full-frame sensor into a beautifully crafted body with a fixed 28mm lens and a spectacular EVF. The SL (Typ 601) does this by forgoing the usual “mirrorless = small” mantra and making a mirrorless camera that is not only on par with some of the latest DSLRs, size-wise, but surpasses many when it comes to features.

Photographs © Shawn Steiner

The camera has a heft that inspires confidence as both a tool and work of art. The craftsmanship of Leica cameras is always high, and this one fits right in line with the company’s previous offerings. The design is also exceptionally clean, with practically no text on any controls, buttons, or dials. Combine this with the customizability of the buttons and you will have an extremely natural setup. Perhaps the best single control implemented on the SL is the rear joystick, for adjusting focus points and zoom when reviewing images and using adapted lenses.

At the forefront of the design specs is a phenomenal 4.4MP EyeRes electronic viewfinder, which is large, sharp, and, most importantly, extremely comfortable. Another less talked-about aspect is the diopter adjustment, which has a clean, crisp click with clearly marked lines so you can quickly and easily return to set places. As an eyeglasses wearer I found this amazing, and it shows how much effort Leica puts into every tiny piece in order to create a beautiful camera that perfectly melds form and function.

Viewing and changing settings is made even easier by the top LCD, in which users can quickly see and adjust settings much like a professional DSLR or medium format camera. One noticeable omission is the lack of a mode dial. This was a brilliant move on Leica’s part, since the rear control dial can be pressed in to access the different modes, which are the classic PASM options.

The rear LCD is exactly what you would expect on a camera of this caliber. One thing I greatly appreciated was the responsiveness of the touch functions, and the fact that you can operate the camera without using the screen at all, if you want. Overall, there is very little to complain about when it comes to the SL’s physical design. Perhaps, if you have smaller hands, reaching some of the more distant buttons could be a struggle, but I must say it is the best mirrorless camera I have ever held. This is partially due to the fact that the grip is full size, similar to that of a DSLR, and something I’ve missed since I moved to the mirrorless format a little more than a year ago.

Along with this larger size is more room for additional connections and ports. The SL sports a fast USB 3.0 connection, a full-size HDMI, a PC sync terminal, and, for some reason, a proprietary connector for additional accessories. This was the first issue I had with the camera, especially since the proprietary connection requires an adapter for headphones and microphones to be attached. The camera is large enough to have had these basic audio jacks built in, and it makes no sense to require an adapter for what many run-and-gun videographers consider a necessity.

On the other side, users will find two SD card slots, the primary being the exceptionally fast UHS-II standard. This gave many people reason to be excited—me included—but I found that when two cards are inserted the camera a “Card Search” function makes quick usage impossible. It requires about 10-15 seconds to boot up and enable image capture, and it does the same thing when waking up from sleep, so leaving the camera on doesn’t make a difference. With one card this issue doesn’t exist, so I don’t understand why it can’t be fixed in a firmware update.

Another issue I personally had was with the setup of LCD/EVF switching. When set to EVF only, it is always on, not just when it is brought up to your eye. This makes little sense, since the EVF is unusable unless it is at your eye and it is a great way to save battery power. This does lead to a huge benefit of the camera, which is the large battery size. It may not quite match up to that of an SLR, but it is leaps and bounds better than any other mirrorless I’ve used, providing upwards of 400 shots on a single charge.

The Basics: Image Quality and Performance

The reasons I moved to mirrorless were simple: image quality and capabilities. The SL has this covered on the stills front. It packs a more modest 24MP full-frame CMOS sensor compared to some of its competitors, but for a majority of your usual applications, this is plenty. Working with the files is made easier with a smaller pixel count and, in the camera, it allows for a fast continuous shooting rate of 11 fps. Along with this, it can reach an ISO of 50000, not quite as good as the a7R II (its main competition and my personal camera), but the noise has a much more organic feeling. Leica’s processing tends to eliminate chroma noise but doesn’t do much when it comes to luminance noise. This retains maximum sharpness and manages to avoid a digital look.

ISO 50

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ISO 6400

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Color rendition is superb, as well, creating a natural-feeling image with distinct colors and smooth transitions. Skin tones are also handled well throughout the ISO range. When it comes to low light, I would easily use the camera at up to ISO 12500—when moving up to 25000 it is still very useable but, at 50000, usage will have to be determined by your own personal opinion. It is decent, considering, but Leica cameras tend to have a pattern in their noise that is very unappealing and noticeable.

Overall, images here are unsurprisingly good and there is nothing to complain about. The camera is fast, and benefits greatly from Leica’s grand assortment of lenses since practically every single lens the company has made is compatible with the short flange distance provided by the mirrorless design.

Lenses, Mounts, and More Mounts

So, it still seems that having multiple mounts is the best way to confuse the buying public. The Leica SL (Typ 601) has the L mount, which is in fact the same as the T mount introduced with Leica’s first mirrorless camera, the T (Typ 701). The reason for the new name isn’t quite clear, but all future lenses will now be designated as SL for full-frame or TL for APS-C. T and TL lenses will work just fine with the SL, but only in APS-C or Super35 modes, and SL lenses will function without any restrictions on the T and future TL bodies, though it appears that the current T will require firmware v1.4 in order to accept the SL lenses. Now that that is over with, let’s get to the lenses or, I guess, just the one lens currently available.

Vario-Elmarit-SL 24-90mm f/2.8-4 ASPH. at 90mm; f/14; 1/50 second; ISO 50

The not-so-classic mid-range zoom, Leica’s Vario-Elmarit-SL 24-90mm f/2.8-4 ASPH. will satisfy many with its relatively fast aperture and extended zoom range, compared to similar options from other manufacturers. While it’s a great starting lens due to its versatility, unfortunately, I wasn’t too thrilled with this one. It is huge! I’m not even comparing this solely to other mirrorless options, it would be large even in the DSLR world. It throws off the balance of the already weighty camera and, frankly, I don’t get it. Performance is fairly spectacular, to a point, and that is where the zoom limits the overall quality.

At the widest end, images are noticeably sharper, even when working wide open. But, after pulling these images into Capture One and looking at the correction profile, there is definitely a lot of work to be done on the edges. There is a bit of smearing and some obvious darkening in the outermost corners, though a majority of the frame does benefit from fairly even illumination. The tele end suffers less on the edges, but lacks some of the pop found at 24mm. This isn’t such a terrible thing, considering 90mm would be an ideal portrait length and photographers may not want to so clearly define imperfections in their subject. Stopping down will solve most of these issues and, at f/5.6-8, the lens is a beauty at all focal lengths. One thing I did notice was that it appears that Leica uses a bit of software correction to guarantee optimal results.

Vario-Elmarit-SL 24-90mm f/2.8-4 ASPH. at 79mm; f/3.9; 1/1000 second; ISO 1000

What is good about the zoom lens and variable aperture is the consistent transition from f/2.8 to f/4 when zooming out. This lens hits f/2.8 at 24mm and f/4 at 90mm with all the other focal lengths somewhere in between (and interestingly Leica will show the aperture in tenths: f/3.9, f/3.8, f/3.7, etc.). It is also internally focusing, though the lens itself will lengthen when moving from 24-90mm, and it gets fairly long.

Vario-Elmarit-SL 24-90mm f/2.8-4 ASPH. at 64mm; f/8; 1/80 second; ISO 100

What isn’t good about the lens system is the use of a focus-by-wire mechanism. In order to focus manually, you must be in MF mode on the camera—there is no constant manual override. The lens does benefit from a mechanical feel, however, compared to competitor’s systems with uneven focusing depending on speed. I did find the system most usable in manual mode, though, due to one clever trick on the part of Leica’s engineers: the joystick on the rear of the camera is used to set the location of the focus point, and when in MF mode, it can be pressed to activate AF, basically providing a back-button AF situation.

One of the huge benefits of the SL, and mirrorless systems in general, is that you can use adapters, such as the M-Adapter-T, in order to use M-mount glass. I was able to take it for a spin and put on the phenomenal Summicron-M 35mm f/2 ASPH. lens. The camera balances beautifully with this combination and I found that this is where the SL shines. It embraces one of the huge advantages of the mirrorless design, shows how Leica is moving forward with its cameras, and calls back to the company’s legendary legacy.

Jumping Head-First into Video

Considering how far Leica is pushing forward, video was one avenue the company had left mostly untouched, until now. The SL (Typ 601) is easily among the best video-capable mirrorless cameras available today, with internal video recording that includes DCI 4K at 24 fps and slow-motion Full HD at 120 fps. But, there are some caveats to this statement. Leica seems to be having some growing pains as it brings video into the fold. Fortunately, the company appears to be listening and working quickly to rectify these issues.

Let’s start with the good. Video is crisp, detailed, and among the best I’ve seen from a camera in this range. Rolling shutter is well controlled and the use of the Super35 area of the sensor results in essentially no moiré or aliasing anywhere in the picture. Also, the joystick in the back allows for silent control over headphone volume and microphone levels and the touchscreen is brilliant for AF control. I was extremely excited to see how the video performed.



Ungraded  Graded using DaVinci Resolve

Along with this, Leica introduced us to L-Log and offers a brilliant 10-bit 4:2:2 output over HDMI, which I was quick to take advantage of using my PIX-E5H Recorder, from Video Devices. This is also where Leica stumbled a little. Internally, on firmware 1.1, internal log recording was unusable since, for some reason, it was severely limited in the shadows, killing all detail. On the other hand, the external recording was near perfect in operation.

During my time with the camera Leica released a firmware update to rectify this situation—sort of. Version 1.2 fixed internal recording but it was then I noticed that there was a problem with low-light recording, since starting at ISO 800 and higher, noise reduction became overzealous and destroyed a lot of detail. It is good that the R&D people at Leica are listening and quickly working to implement fixes, but they really need to get this done faster, and have better testing for a camera of this caliber.

ISO 400 ISO 800

As a freshman effort, I must say I was impressed. When the footage falls within certain workable parameters it can be amazing; it's the odd restrictions that are holding it back and, hopefully, will be fixed soon.

Final Thoughts

Leica will have an excellent camera with the SL (Typ 601), once designers iron out all the bugs. It is the company’s first full-frame mirrorless option, and the first to boast incredible video, so some of the errors are understandable. At its core, it is one of the best cameras I have used. It feels good, works quickly and intuitively, and inspires me to keep shooting. I can’t wait to see what Leica has in store next.

Proving that Leica has a dedication to its products and customers, the company has just released Firmware Update 2.0 for the SL (Typ 601) Mirrorless Digital Camera. Available to download here, and user installable, this firmware update brings a host of new features and improvements to the table.


I would likely use this body for live theatre and performance work.

Having used an M4-P to good effect in film days, and being Horrified at the racket the M9 made, how loud is the "shutter noise" in this camera.

Also, how easy is the access to altering exposure (+/- half a stop/ 1 stop/ 2 stops?) 

Hi Marek,

It is an extremely quite camera, and if you are in a semi-auto mode it is extremely easy to access the exposure compensation. It you are in manual it is really easy to control everything as well.

What are the chances of this receiving 10bit internal recording at some future update? 

Call me crazy but I would actually consider saving money and getting one. I am that impressed with it. But I don't want to buy a camera that can't do 10bit internal video recording to be future proof. If I'm dropping 7 grand on a camera, it better has features to stay up-to-date for the next years to come. 

Without 10bit, this is the almost perfect camera for me. 

Hi Dave,

I would say it is highly unlikely, if not impossible. I would love for 10-bit internal, but it will dramatically increase processing power so I would be absolutely astounded if Leica can pull off something like this in a simple firmware update.

Not a word about peaking? My main reason for jumping to mirrorless, subsequently selling my M9 3 - 4 years ago . . .

Hell Odd Geir Sæther,

The Leica SL does have peaking, sorry it did not get a specific mention in the review as for the video testing (where I used peaking the most) I had a Video Devices PIX-E5H Monitor/Recorder which has its own peaking options. The SL has multiple colors and strengths to choose from.