PMA 2009 – Day 1 – More Details on the Leica S2

I headed over to the PMA show this morning and went straight to the Leica booth to find out if there was anything new and exciting that wasn't in the pre-PMA announcements. No such luck. No M9, R10, digital CM, or <insert other oft-rumored product here>. All the new lenses, SF 58 flash, and Safari Edition M8.2 were on demo, and even better, I was offered use of some of the lenses to go shoot the Las Vegas Strip tomorrow night. So, after the show on Wednesday I'll head out for the blue hour and beyond with my M8.2, the new 18mm Super-Elmar-M ASPH and the just-starting-to-ship 24mm Summilux-M ASPH. Sweet. And, because these are full production lenses, I can post all the pictures I want. Whoo-hoo.

My day was pretty much filled with various meetings inside the Leica booth. I got even more time than I had anticipated with Stephan Shulz and Andreas Wahlich. Stephan is the S2 product manager and Andreas is the S2 sales manager. Both are extremely knowledgeable on the S2 and were great about answering all my (many) questions. They caught me up on the developments since Photokina and we discussed some of the S2's strengths.

Let's start with some basics. The Leica S2 is still on target for shipment in summer 2009. Contrary to what you may read online, the S2 was always scheduled to be launched in summer and is not delayed. The camera will probably be available in two versions, with and without a sapphire glass LCD screen. This may seem like an odd differentiator at first, but does actually make sense. Making a 3 inch piece of sapphire glass is extremely expensive. As it is, the sapphire glass on the M8.2 is already one of largest manufactured at 2.5 inches. The extra 1/2 inch adds greatly to the cost. So, the model without sapphire glass will cost a decent amount less for those that don't require it. But, this camera is aimed squarely at the professional market. Rental houses and commercial studios can really benefit from the stronger, scratch-resistant screen. So, if the camera is destined for rigorous use and not-so-careful handling, sapphire is the way to go.

The S2 will ship with three lenses at the outset: The 70mm, 120mm Macro, and 180mm. The 35mm will come very shortly after in early fall 2009. Then, by the end of 2009 the 24mm and 30-90mm zooms will ship. The fast 100mm, 30mm T/S, and 350mm will follow on in the first half of 2010. The other interesting twist to the story is that the four CS lenses with leaf shutters will also be offered without leaf shutters as well. The reasons behind this are very simple. Not everyone needs a leaf shutter for their photography and the non-leaf-shuttered lenses will cost less. I happen to think this is a very customer-friendly approach. Rental houses and serious fashion shooters will opt for leaf-shuttered lenses, but a landscape photographer will only use the focal plane shutter. Those that don't need it have the option of paying less. The CS lenses were designed with this modularity in mind. The optical and mechanical design is identical, but the shutter module can be omitted.

Okay, now some cool techie-geeky stuff. Because the S2 is designed completely from the ground up for digital, it has some real tech advantages over existing MF systems. For example, in a typical MF digital back there are two pieces of glass over the CCD. The first is a protection filter, the second an IR absorption filter. In the S2, the IR filter is fused directly to the sensor. So, there is one 1mm piece of glass in front of the CCD. Now the really cool part is that Leica, being the perfection-obsessed (but in a good way) optics company they are, designed the S lenses with the IR filter as part of the optical path. The optical formulation carries through to the sensor cover glass, which does impart a shift in light rays. Current MF backs create spherical aberrations when used with lenses designed for film. Stephan explained how Leica was able to realize certain advantages because they didn't need to cater to film and digital. You might wonder how other manufactures deal with the introduction of spherical aberrations. They correct it partially in software by sharpening. The aberrations and subsequent software correction serve to create rougher transitions from in-focus to out-of-focus areas. The S lenses promise to deliver exceptional bokeh and buttery smooth focus transitions.

I did manage to get a few more details on the Kodak KAF-37500 CCD sensor used in the S2. It does, in fact, use offset microlenses, just like the M8 and DMR. So, this will be the first medium format sensor to utilize this technology to dramatically reduce sensor vignetting. It works extremely well and is proven tech. Why no one else uses offset microlenses is beyond me. The A/D converter is 14-bit. There has been a lot of discussion and confusion on this point. I inquired, "why not 16-bit?" The sensor has a native 12 f-stop dynamic range. 12 bits is sufficient to contain this information, meaning that there is an extra 2-bits of headroom. A 14-bit A/D can contain 14 f-stops, so 16-bit would be overkill and unnecessary. Stephan explained that earlier in his career he worked for Phillips in CCD development. So, I'm going to take his word on this. I asked about sensor cooling. The CCD is mounted on an aluminum plate, which is then attached to the magnesium alloy chassis. So, essentially the camera body acts as a giant heat sync. Not active cooling, but well thought out, nonetheless.

Many want to know the ISO range of the S2. This is not written in stone yet, but 800 ISO is a certainty with 1600 (or more) a definite target. Much of this depends on the sensor readout board and getting the cleanest signal off of the CCD. These signals are analog and are subject to noise. So, the more efficient the readout, the less noise is present heading into the A/D converter. This means that less high-frequency clipping is required to reduce noise. If you clip this data, you are essentially discarding resolution. And nobody likes that, do they? On that note, though, the S2 will implement optional pixel-binning. You have the option in the current firmware to select DNG output resolution of either 37.5 MP or 9.3 MP. The 9.3 MP is the result of combining four pixels (2x2) into one. Theoretically, this should allow one to two stops extra ISO with the same noise characteristics. If the S2 can turn in good 1600 ISO performance at full res, then by pixel binning it should be able to deliver good 3200 or 6400 ISO shots at 9.3 MP. Not too shabby for a medium format camera and 9.3 MP is fine for prints up to 20x30 inches.

To answer another frequent question, Live View functionality will not be implemented on the S2. While this is unfortunate, Leica is well-aware that this is a feature they need to offer in the future. I was led to believe that this will be included in future cameras. Apparently, given the sensor architecture it was just not technically possible with the S2. The heat generated would be extremely high and lead to unacceptable noise in the final image. Leica is also exploring the possibility of using CMOS sensors in the future, as it would allow Live View and some other features. Frankly, I was surprised to hear this, but I'm sure I'll eventually get over my CCD-loving ways when the time comes. The current sensor does allow for long exposures, though. When posed with the question whether the camera would shoot an exposure longer than 30 seconds, Stephan switched the shutter dial to Bulb and clicked. We watched the top deck OLED as it counted up in seconds (another nice touch I think). It went past 30, then past 60, then past 100, then Stephan got tired of holding the shutter. He told me that there is no limit in Bulb mode. In Program mode, the maximum exposure time is limited by the light meter's minimum EV sensitivity. Of course, if you shoot a really long exposure, be prepared for a really long dark-frame subtraction. After that, the internal processing on the S2 will look for any hot pixels that the dark frame missed and correct them. In other words, you can use the S2 for night shooting. And, don't worry about holding the shutter in for your long night shots. There will be a dedicated electronic cable release as one of the earliest accessories.

Let's talk a bit about Auto Focus on the S2. The big news first. Several people have asked me about programming the top right button to be AF-on. Well, Leica has provided an even better option. There will be a separate AF-on/lock button for your right thumb to enjoy. This is a new button that is not on the current prototype but will absolutely be on the final product. Good news, huh? There is also more to the lenses than meets the eye. I wanted to know if there would be user fine adjust from the camera. No….but, the lenses actually will be programmed at the factory with some interesting data. Each and every lens will be tested for focus accuracy. Any fine-tune adjustment will be dialed in so that this correction follows the lens on any S2 body. Also, each lens has extremely precise info on actual aperture information. f/8 on one lens might really be f/7.96 or f/8.02 on another due to the physical aperture having minute variation. Because the S2 compensates for aperture-based focus shift (yes, you read that right) the camera needs to know the exact aperture to calculate the adjustment. If you are into manual focus, you will feel right at home with the tactile feel of these lenses. Also, you'll have the option of several interchangeable focusing screens: standard uniform ground glass, microprism field, split-image, and grid. There is also a very good chance that there will be a screen with 4:3 frame markings for those that want to shoot page-safe for magazines.

Next, I'd like to address some lingering speed specs. The frame rate seems to be set at 1.5 fps, which is still faster than just about any MF system right now. It won't win any speed contests with a D3 or 1DIII, but it's pretty fast for close to 40 MP. We already knew that the S2's buffer is 1GB, holding about twelve 75 MB DNG files. Some simple math says that we'll hit the buffer in about eight seconds, but life is never simple. The S2 is already optimized to take advantage of the new UDMA 6 specification, which allows up to 96 MB/sec. According to Leica, with one of those yet-to-be-released 600X UDMA 6 cards, you can shoot continuously until your card fills up. The Maestro and internal bus are not the limiting factor as they are pushing through about 120 MB/sec. This is one camera where you do not want to skimp on the card. Get the fastest, biggest card you can. As I mentioned in my Photokina report, the S2 is crazy fast. Startup time from off to shooting is less than 0.3 seconds. Image review is instantaneous, as is zooming and scrolling.

Another speed question, and one that I'm particularly interested in myself, is the sync speed on the leaf shutter. The answer is "at least 1/500th of a sec, hopefully more." I asked about meeting or beating certain market competitors. Apparently, the team at Leica benchmarked their competitors and what is claimed on spec sheets is not always reality. The Sinar Hy6 with PQS lenses actually syncs at 1/750th not 1/1000th. The H3DII was clocked at 1/650th not 1/800th. Stephan gave me a brief education on leaf shutters. Leaf shutters do not work in a vacuum. Their speed is dictated by the aperture setting as well. The exposure time will actually double from wide-open to fully stopped-down. In other words, a leaf shutter that can sync at 1/500th wide open can only sync to 1/250th when stopped down. Most manufacturers rate their shutters for wide-open performance. Leica finds this method inaccurate. So, they will actually rate the shutter for stopped-down speed and slow it down as the aperture is opened up. This way, there is no exposure shift at varying f-stops. This means that Leica's 1/500th spec applies to all apertures.

I know this is getting to be a lot of information, but here are a few more neat things I learned today. The S2 offers the largest exposure bracketing range I've ever seen on any camera. You can set it up to go from -6 EV to +6EV in either half or whole stops. This would result in a 25-shot exposure sequence if you use the entire range in half stops. HDR lovers rejoice. This led my mind to focus bracketing so I made the suggestion. While a feature like that won't be shipping with the camera, it is something that Leica would consider adding. We discussed about a half-dozen possible future features, like a hyperfocal distance aid on the OLED. Another really cool feature is the ability to back up all your menu and profile settings onto an SD card. That profile can then be loaded onto any S2 to clone the camera quickly. Rental houses will love this for getting a camera back to "house defaults." Photographers who rent can store their own personal settings on a spare card and load it into any camera from any rental house quickly and easily. With a camera as advanced as the S2, this is a great pro feature.

The S2 is incredibly well thought out from both a user and an engineering perspective. The interface is simple. The quality is uncompromising on so many different levels. Leica has managed to make tremendous improvements in the short time from Photokina until now. Stephan and Andreas assured me that this was because all development and manufacture is now in-house. Such an undertaking would not have worked if Leica needed to depend on technology partners. All-in-all, the S2 is shaping up to be a truly professional tool. Is it summer yet?!!