BobT wrote:
I'm especially comparing them to entry level DSLRs. I'm reading statements like this of late. Some, like the recent NEX line state the Nex's have noticeably better IQ than DSLRs. So has the mirrorless surpassed it's main original benefit of just being smaller and lighter? Will pros or semi-pros be looking at these "smaller" cameras as their "main" cameras? All this has me thinking about replacing my DSLR gear with mirrorless.
The answer is found in a question: "Better, compared to what?"
Most mirror-less cameras are lighter and smaller than dSLRs. Micro-Four-Thirds cameras, in particular, can be one third to one fourth the size of dSLRs, with much of the same capability. This makes them particularly inconspicuous, and extremely easy to backpack or travel with. You can carry the same amount of gear with much less fatigue. A bag with two bodies and a "holy trinity" of zooms, plus a portable flash, batteries, and a monopod, can fit under an airline seat.
There is no reflex mirror to flip up. So mirror-less cameras don't black out the viewfinder at the moment of exposure.
They can and at the higher end of the market do have very good electronic viewfinders integrated into the body in "dSLR style." The advantage is that you see a live JPEG rendition of what the camera will save. The disadvantage is that there is a tiny lag. With each generation of camera, the lag is getting shorter.
The Sony A7s and the Panasonic Lumix GH4 feature outstanding video performance, better than the Canon 5D Mark III. The A7s wins in low light, and the GH4 wins most everywhere else. Dave Dugdale has a comparison video on YouTube that is quite enlightening!
The A7 Series full frame Sony cameras have some of the highest dynamic range sensors you'll find on the market today. Their low light performance is great, and their daylight performance has great color depth.
Micro-Four-Thirds cameras have access to the largest body of lenses on the planet. The native lens line (from Panasonic, Olympus, Leica, Voigtlander, Samyang, Tokina, Sigma...) is extensive.
http://hazeghi.org/mft-lenses.htmlWith appropriate adapters, your existing Nikon, Canon, Pentax, ciné mount, and other lenses can be attached to Micro-Four-Thirds cameras, although functionality is usually manual.
Fujifilm's cameras feature excellent dynamic range, and some very accurate film simulations are built right into the camera. Their JPEG output is very, very nice.
On the flip side:
The mirror-less offerings from Canon and Nikon are paltry. Canon's EOS-M line has received generally mediocre performance reviews and luke-warm enthusiasm. The Nikon-1 series has a tiny little sensor that disappoints in low light. Adapting these cameras to longer Canon and Nikon lenses can be pretty humorous, as the cameras are very small.
Sony and Fujifilm are slowly building their lens lines for the A7 and X-series cameras. While their optics are quite good, they aren't as full-featured, as fast, and as plentiful as many photographers would like.
Micro-Four-Thirds sensors are about one fourth the area of full frame (35mm size) dSLR sensors. This reduces the potential maximum ISO by around two f/stops, and increases the depth of field by two f/stops, by comparison. The difference is only about one stop for ISO and DOF when you compare m43 to APS-C or DX.
So far, m43 sensors are mostly limited to 16MP. That's enough for most purposes, until you want to crop huge prints from small sections of the frame, or render maximum detail in very large prints that will be viewed from a few inches.
High end full frame and APS-C dSLRs are still king when it comes to raw speed. Sports and "bird in flight" nature photographers still should be hesitant to adopt mirror-less cameras.
So, again, the answer is that it depends upon what you want to do. If you are getting older, and want a camera system that travels well, maybe an m43 of some sort is in order.
If you want the best video bang for the buck, take a close look at the A7s and GH4.
If you want to make images that remind you of Fujichrome Velvia, try one of the X-series cameras.
If you photograph landscapes, try the Sony A7 series.
If you spend most weekends on the sidelines of a sporting event, keep your high-end dSLR gear. If you photograph animals in flight or on the run, keep your dSLR gear.