[Clavius]

You do realize that most mirrorless cameras are TTL, right?

No they're not. Mirrorless camera's are through a screen, other electronics, software, sensor and only then the lens.

Not only that, but some can be set up to always show DOF preview, or 16:9 preview, or 1:1 preview or B&W preview, or show a live histogram, or any number of things an OVF can't do.

Liveview already does that, and it's bigger too. Now, we can choose between OVF and liveview when we want and/or adapt to the circumstances. With a mirrorless camera, that choice and freedom is gone. That's why the term mirrorLESS is so correct. It says that something is missing.

[RobA_Oz]

No they're not. Mirrorless camera's are through a screen, other electronics, software, sensor and only then the lens.

So, no they're not, but yes they are? Well, mirrored cameras are through an eyepiece, then a pentaprism (or pentamirror), then a focussing screen, then a mirror, and only then through a lens. That's a count of five things, too.

Liveview already does that, and it's bigger too. Now, we can choose between OVF and liveview when we want and/or adapt to the circumstances. With a mirrorless camera, that choice and freedom is gone. That's why the term mirrorLESS is so correct. It says that something is missing.

Sadly, Liveview is a problem when it comes to autofocus (it isn't fast, and Pentax doesn't give us any AF in video mode). Liveview's great for some things, like fine manual focus, particularly with macro work, but it's not fabulous elsewhere. Choice? It's a bit of a furphy in this context.

[Clavius]

So, no they're not, but yes they are? Well, mirrored cameras are through an eyepiece, then a pentaprism (or pentamirror), then a focussing screen, then a mirror, and only then through a lens. That's a count of five things, too.

The light doesn't get interrupted with OVF. With mirrorless the light stops at the sensor. The image that hits the eye isn't real. So, it's not seeing through the lens. A bunch of elektronics and software interprets what's supposed to hit the eye. The displayed image doesn't match reality, nor matches the eventual output image dat is saved to the card.

Sadly, Liveview is a problem when it comes to autofocus (it isn't fast, and Pentax doesn't give us any AF in video mode). Liveview's great for some things, like fine manual focus, particularly with macro work, but it's not fabulous elsewhere. Choice? It's a bit of a furphy in this context.

The autofocus in my NEX5n wasn't any faster then autofocus in the liveview of my K5. Why? Because the slow AF is inherent of contrast-AF. The K5 liveview uses the slower but more accurate contrast-AF, whilst the OVF uses Phase Detection. The NEX is limited to contrast-AF only.

So "no", not very furphy at all.

And as for video mode: That's what videocamera's are for. The video-mode is a nice-to-have by-product, but can be stolen for all I care. Personally, I would even have preferred a CCD instead of CMOS: No video or liveview, but better IQ.

[Rondec]

There are a number of reasons why people (not sure if that includes me) want mirrorless. Smaller size (not necessarily to replace an SLR, but to complement it), cheaper price, more accurate focusing (not requiring adjustments for each lens), and often the ability to mount a wide variety of lenses with an adapter (assuming a shorter registration distance).

The problems are also many. Most don't seem to include an EVF and even if they have an EVF, they still aren't very good (although pentamirror viewfinders aren't very good either). Contrast autofocus still isn't as good as phase detect autofocus.

There are pluses and minuses, but I think that it is clear that lower end SLRs are eventually going to be replaced by mirrorless cameras.

[L33tGreg]

My biggest gripe with MILCs is the lack of phase-detect af.

[Marc Sabatella]

I think you misunderstand what TTL means, and what it's an alternative to. The opposite of TTL is a range finder, where the light emtering the viewfinder (whether optical or eletronic) does not pass through the lens *at all*. So the viewinfder is not showing what you see through the lens - it is showing slightly different line of sight (which introduces parallax problems), it doesn't show the actual FOV or focus or aperture of the lens, etc. Some of that has been at least corrected for in sophisticated rangefinders, so the experience isn't quite as bad as it otherwise might be, but any TTL design - again, whether the final viewfinder display is electronic or optical - will be immune from those problems.

Now, while electronic as opposed to optical viewfinder are both TTL, there are of course differences, but some of those differences favor electronic, and others favor optical. The fact that the image has been processed in the electronic version does mean it has the disadvantages you state, but you failed to mention the advtantages it has, such as the act that the focus is guaranteed to match and not be subject to the slight discrepancies that can plague optical viewfinders. Furthermore, the lack of a mirror itself means simpler mechanical design, leading to quiter operation, less camera-induced shake, probably longer life, etc.

But none of that has anything to do with whether it is TTL or not, because both designs are clearly TTL. You can't co-opt that term that has had a well established meaning for decades now to mean something else. TTL means what it means, and anything in which the light that forms the viewfinder image enters the camera through the lens is TTL, period.

[JHD]

My biggest gripe with MILCs is the lack of phase-detect af.

Not so. Nikon 1 uses a hybrid AF that uses both phase and contrast detection. The AF and tracking is among the best of the best.

[Wheatfield]

Why does anyone want a mirror less camera?

Because it's the latest tech.

[kh1234567890]

I think you misunderstand what TTL means, and what it's an alternative to. The opposite of TTL is a range finder, where the light emtering the viewfinder (whether optical or eletronic) does not pass through the lens *at all*. So the viewinfder is not showing what you see through the lens - it is showing slightly different line of sight (which introduces parallax problems), it doesn't show the actual FOV or focus or aperture of the lens, etc. Some of that has been at least corrected for in sophisticated rangefinders, so the experience isn't quite as bad as it otherwise might be, but any TTL design - again, whether the final viewfinder display is electronic or optical - will be immune from those problems.

There are times when a rangefinder option is handy. Even the best LCD or LED screens can be pretty useless in bright sunlight. Unless you are very myopic you end up holding the camera at arm's length which is not the most stable of poses. And there is always going to be this annoying time lag between reality and the LCD display. One of the reasons why I still keep an old Sony W1 point-and-shoot with a pretty naff but handy optical rangefinder type viewfinder.

[JinDesu]

Because I have an iPhone

[RobA_Oz]

The light doesn't get interrupted with OVF. With mirrorless the light stops at the sensor. The image that hits the eye isn't real. So, it's not seeing through the lens. A bunch of elektronics and software interprets what's supposed to hit the eye. The displayed image doesn't match reality, nor matches the eventual output image dat is saved to the card.

The autofocus in my NEX5n wasn't any faster then autofocus in the liveview of my K5. Why? Because the slow AF is inherent of contrast-AF. The K5 liveview uses the slower but more accurate contrast-AF, whilst the OVF uses Phase Detection. The NEX is limited to contrast-AF only.

So "no", not very furphy at all.

And as for video mode: That's what videocamera's are for. The video-mode is a nice-to-have by-product, but can be stolen for all I care. Personally, I would even have preferred a CCD instead of CMOS: No video or liveview, but better IQ.

This could keep going forever - Marc's post says it all, really, as far as I'm concerned.

Don't get me wrong in this - I still prefer an OVF to an EVF as things stand, and the latest news on the K-01 doesn't really convince me I should be getting one in preference to, say, an XPro-1, although we don't know K-01 pricing yet, and the XPro-1 is a little on the pricey side.

[Lowell Goudge]

from my perspective, there are pro's and con's to a mirrorless camera.

the biggest advantage for the camera maker is that by removing the mirror box, prism housing etc, there is the possibility of greatly increased shutter rates because the mirror is, well, gone and the mirror up time is a big part of the frame rate budget. (i forgot to mention cost savings as well. Mirrorless is also the first step towards electronic shutters.

the down side is that in low light electronic eye level view finders are pathetic. Although this may improve.

what I am not sure about is how the viewfinder will function and shutter lag. Now you have to close the shutter just to shoot. oops!

[johnmflores]

I really don't understand this fear of shutter lag due to mirrorless and/or no OVF. It doesn't exist with Panasonic Micro Four-Thirds.

[Wheatfield]

I really don't understand this fear of shutter lag due to mirrorless and/or no OVF. It doesn't exist with Panasonic Micro Four-Thirds.

OOOh, you got a well timed picture. It says absolutely nothing about viewfinder lag though.

[johnmflores]

OOOh, you got a well timed picture. It says absolutely nothing about viewfinder lag though.

Yes it does. People are worried that viewfinder lag will prevent them from capturing the decisive moment. It won't.