Are mirror-less cameras good enough to buy instead of a DSLR for home/amateur use?

Question

I'm an amateur photographer looking to buy a camera for my home use. I called myself "photographer" just because I actually can press the button and take a photo! My first digital camera was VGA resolution (640×480px) and didn't even have a display (!), and after that I just used my phone as my camera.

Anyway, when I compare photos that taken with a professional camera (DSLR) and point-and-shoots, I can see that the difference is huge in terms of quality! Even DSLR cameras with fewer megapixels give better pictures than a higher-megapixel point-and-shoot.

I was considering the Canon Rebel T3 (18MP) DSLR, but when my wife saw that in Best Buy, she was scared of the amount of buttons and options on it. She said we need to take some classes to use it! I know this camera should have an "auto" mode that would be easy to use, but she still didn't like the camera and was scared of not being able to use it.

Then I researched around, and found "mirrorless" cameras interesting because they have DSLR quality in point-and-shoot form factor. But they seem to be "beta versions" of a concept. Most of them don't have flash or microphone, and are very expensive. I liked the Sony NEX-5 but as I said, the camera does not seem perfect.

Are the mirrorless cameras are limited by their nature, and we can't have all DSLR features in a small camera, or we will see some models that are perfect?

Answer

Those cameras are only limited by the fact that they lack a reflex mirror to form an image through an optical viewfinder. By the same token, DSLRs are limited by the fact they need a reflex mirror in the optical path.

What does that mean?

• In terms of image quality, nothing. There are currently mirrorless cameras using the same sensors as DSLR. Even those with slightly smaller sensors (all except the Pentax Q) are not far behind.
• In terms of speed, not much. Current DSLRs are faster than mirrorless cameras at autofocus because they use Phase-Detection rather than Contrast-Detection. This is not an an intrinsic characteristic, as phase-detect can be implemented on the sensor (as in the Fuji F300 EXR) or in the optical path using a semi-transparent mirror (as in the Sony Alpha SLT-A55). Other aspects of speed such as shutter-lag, continuous drive are very similar.
• In terms of versatility, mirrorless cameras have more potential. The shorter flange-distance lets mirrorless cameras use more types of lenses via adapters than any other type of camera. One neat trick is that you can buy a tilt-shift adapter that adds that capability to a DSLR lens when mounted on a mirrorless camera.
• Mirrorless cameras are presently limited. They key is presently. They are limited in number of native lenses which are relatively new compared to DSLR lenses. They are also limited in functionality because there are not that many models. For example, there are no weather-sealed mirror-less cameras and there are none with a built-in GPS.
• In terms of size, mirrorless cameras are smaller and lighter. This is an intrinsic advantage of the form-factor. Even those with a built-in EVF can be made very compact.

Mirrorless cameras also have advantages for video as they can be used at eye-level with a built-in or optional EVF. You are right that a few models do not have a built-in flash but some DSLRs don't either. Those particular models are trying to show how small a mirrorless camera can be, but that does not mean you have to buy the smallest. A Panasonic GH2 for example is reasonably ergonomic and quite full-featured.

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