Mirrorless cameras in this post are the interchangeable lens cameras similar to a DSLR. Also called MILC's or CSC's. Mirrorless cameras are not the coming thing. They are already here. Whats the big deal? Why all the fuss over the DSLR cameras which are proven and evolved? Its just a camera, right? Well...mirrorless cameras ARE the next generation of imaging devices. They have the next gen features like touch screens, built in wi-fi and GPS location info, but the biggest benefit is because they can be made smaller, and lighter in weight. Plus not having a mirror makes them perfect for hybrid video and stills use. So you can effectively do both types of imaging, video and stills, and do it well with one camera. No compromises. Because mirrorless cameras use electronic viewfinders (EVF), which are mini TV's, your scene can be depicted EXACTLY as it will look to the sensor in terms of exposure, white balance or film simulations and you can alter this on the fly to model effects. The EVF allows for "focus peaking" a focusing feature which is useful in video and stills work to obtain exact focus manually. So they are really great with older manual lenses. Ironic right? Pretty tight package, eh? With the current technologies in play plus with whats coming they will (or can?) finally match the feature set and performance of a high end DSLR. And actually hold the promise of offering more. Heresy? Blasphemy?
The provence of DSLR's has always been that auto fast focus ability coupled with a most excellent viewfinder which lets you track and follow a subject as it moves, never taking your eye off it. The higher end pro models offer ultra fast bursts of speed like up to 14 or even 16 fps. And excellent hi-speed processors to handle the data requirements. Great for sports, some wildlife and even in studio with dancers or fitness subjects moving quick. Hell, even some models move really fast! I've used high speed bursts to ensure the first kiss shot at a wedding. DSLR's can focus in very low light too. Like candlelight or "no moon" low light. The pro level equipment is reliable, weather proofed and serviceable - although many would challenge that last statement - truth is the DSLR's from Canon, Pentax and Nikon (among others) have pretty good performance track records across a lot of use cases. They have been to war, and to outer space and all the in between. Still the choice for rugged dependable use. But we all still carry backups - added weight.
Mirrorless cameras are less proven right now. Early on, they struggled with low light focusing and many other issues that DSLR's handled easily. Two years later, those issues are moot. My Fuji weather sealed cameras have performed right next to my Nikons in poor weather. High usable ISO performance is available and several can focus "in the dark". There are still, however, a few key reasons I keep the DSLR at the top of the photo chain: 1) demonstrated reliability, 2) focus speed, 3) that faster frame rate when I need it and 4) excellent battery life. Mirrorless cameras eat batteries. They do consume power like a hungry dog and with all the electronics involved suffer from heat build up issues which affect reliability. Reliability will come I feel, its just going to take time for the engineering and technology to develop. We need more data to track failure rates and cause, and to sort the bugs out of the electronics all mirrorless cameras depend on to control things like focus, exposure, and other features packaged as a whole. That will come and newer iterations of models are already showing progress. It does take a lot of energy to power the EVF, and other components packed in that small housing. My Fuji X-T1 suffers on hot days when used for hours at a time. So does my older X-Pro1. My newer X-Pro2 has shown improvement so its being addressed. Bigger batteries would help but they can't be too big or the size advantage of the body is negated. A proper fix may need new technology or perhaps as is the case with Fuji's new X-T2, an engineering work around using multiple batteries and optional hardware to up the shot count. Until, at least, something new can be developed at a cost acceptable to marketing and consumers.
With the new Fuji X-T2 and it's optional grip you can run with three batteries and specs say up to 1000 shots. Marketing aside, I hope for 500 and I would be happy. I get about 115 now per battery which is terrible performance. I measure my DSLR's battery performance by the week. I can use and use and get one to two weeks on one battery. Rarely do I need to put one in every other day. The Sony A7 series is super popular right now with the enthusiast crowd and it has very poor battery life; so do all other mirrorless cameras. I would welcome some form of reliable power monitoring as a stop gap measure for battery life. Just let me know when the battery is close to it's end. The X-Pro2 is a power hog and when it's battery goes, it goes with no warning. Just full bars shown on a crappy, cheapy barber pole gauge then a red battery silhouette across the LCD and seconds later its off. After maybe 110-115 shots. Studio acceptable (barely) but not field acceptable.
I hope the newer X-T2 with the same internals as the X-Pro2 will become my field acceptable answer. It should handle more than 115 shots, having three batteries. It uses 325 focus points now, 69 are sensor based phase detection types for speed (Fuji and most mirrorless focus systems are VERY accurate if not fast) and it has 5 new canned focus routines for coupling the type of shooting to a focus mode. This is very DSLR like. With the battery grip and its 3 batteries, it offers 100 fps performance in the viewfinder! So no blackout! You can track and follow a subject just like a DSLR! You can shoot at 11 fps rate too for fast moving sports. A big plus for me, as someone considering doing more video, is its ability to record 4K video for up to 30 minute segments WITHOUT overheating - something a Sony cannot do. Not to be overlooked from a system perceptive is Fuji's ace in the hole; it's lenses developed for the X system cameras. It is the finest glass available, in my opinion, from a cost to performance ratio. Think Leica and Zeiss performance but at Fuji prices. This is perhaps the first true system that could replace a complete DSLR system used for professional use.
As good as all that sounds, Hasselblad has also introduced a mirrorless game changer. It's X1D model is a mirrorless MEDIUM FORMAT camera. First. Ever. Anywhere. They packaged a 50MP sensor (same sensor and processors used in their top of the line H5 model) into a body not much larger than a Fuji X-T1 body and way smaller than a Nikon D750 body. I won't get into the performance specs of the system here, but just understand its something to behold. Glass matters with hi res sensors so Hasselblad is building a line of lenses for the X1D and they are very good. Two will debut with the camera in a few months and another is coming in January. This is very serious stuff for a portrait still shooter or those that chase landscapes, cityscapes or specialize in nature. Its being billed as a street camera and Ming Thein can show you how on his blog. I have had limited time handling one at a local demo day and it is a treat. The images are THAT good.
I want to mention my own thoughts about pixels and sensor sizes. Fuji and the other manufactures of APS-C sensor based cameras are pretty much at max pixel count for those sensors. Its about 24MP right now, which is a good number for all around performance. I've always thought 35mm full frame sensors benefited most from something in the 25-30MP range and my current D810 at 36.3MP bears that out. I have pixels to spare. In the 645 size sensor format, 50 to 60MP is a good number. Sure you can cram more into any sensor but you change the equation in balancing performance and features to sensor size. You get higher heat, higher signal to noise ratios, less sensitivity, more power consumption, and on and on but not better photographs. I've seen the 50MP Canon full frame and the Sony full frame cameras output, and while they are good, they don't offer - to me - anything more than my lower 36MP Nikon. Actually, I've found my 24MP D750 full frame to be more than enough. In some performance indices, I think the high pixel 35mm cameras offer less. The medium format cameras do offer more. Gobs more. They always have, but they were mostly big (if you could afford one) to lug around. Medium format glass is very expensive and very heavy - even the X1D's lenses as svelte as they are for MF glass are big. I've rented medium format and while the photographs were and are glorious, Price plus size just never did compute for me. The Hasselblad changes all that. It performs. Its got the same mirrorless power issues, maybe 150-250 shots - which I will have to see to believe. It does have a huge battery though. I'm not getting much info on it's auto focus system performance either, but single point AF works for a 1.5 fps camera. Its not supposed to be fast. It has some definite pluses though, enough of them to have me this close (thumb and forefinger 1mm a part) to pre-ordering. If it works as spec'ed and advertised, its $15K price for a body, two lenses and 4 batteries will be a no-brainer. If you need and can use such a system that is. Not every one will.
So theoretically I, or others, could go all mirrorless in a year. I could be a Fuji and Hasselblad guy. A year though is a long time in the imaging world. A year ago I could not have even conjured the idea of writing such a sentence. I wonder what a year will bring in terms of new offerings and technology? I hear Fuji, Canon and Sony are also looking at the medium format market. Nikon is rumored to be looking at higher pixel count full frames - and to me thats a mistake. But its their call. The technology card is the wild card here. Some cool tech could come out that negates one format versus another but no matter what, I think mirrorless, across any format, is going to be the heavy hitter. Yes, some high end DSLR's (D5, 1DX - and their generations) will endure and be needed. But I think the bulk of the high end consumer and higher end pro market will be moving to mirrorless and who knows? Maybe to mirrorless larger format.
Edit Update: As I got ready to press the Publish button on this post, I felt that I never really stated my current opinions on mirrorless. So in a nutshell here is why I'm excited about the technology and why I am not.
Plus: Super accurate focus. DSLR's may be quick but the hit rate for accuracy belongs to mirrorless. No need to AF fine tune a lens as needs to be done on a DSLR. Weight and size is huge, especially when traveling, or working an event or even a wedding and you are shooting from 5 to 12 hours per gig. Integrated wi-fi. Pro level hybrid video and stills ability in one unit.
Cons: Still kind of quirky. Viewfinders and LCD screens can sometimes have a mind of their own. Traditionally slow focus. Overheating. Overall reliability.
Admittedly, the cons are going away or appear to be based on manufacturers announcements. Lets see if thats really the case. I will still keep my Nikon equipment very close by while I test since I cannot afford to screw up a shoot because of "new equipment". It will take me a while to develop that trust with mirrorless.