ReyeR:
That's not how I understood it. The mirror in front of the image sensor is fully reflective, just like a conventional SLR. The light path is normal, through the focussing screen and then reflected twice through fully reflective mirrors. [........]
The mirror in front of the image sensor will flip out of the way when the shutter is released, just like a conventional SLR. This means the "Live" view on the LCD display will also black out at that time.
This does mean that the optical viewfinder will be dimmer because some of the light is directed at the "Live" view CCD. But it will have no effect on the auto focus system.
Hmm... No, the "Full time Live View" requires a partially silvered mirror in front of the sensor. It's new for digital SLRs, but really an old idea from movie cameras. In fact, the E-330 specification lists the mirror as a "half mirror" meaning half silvered.
I've inspected many old movie cameras with interchangeable lenses that used the same concept, a partially silvered mirror to split the image to the film and viewfinder. What's old is new. As a historical note, the double porro prism viewfinder image path is very similar to the one in the famous Olympus Pen F SLR of 1966, which was extremely successful. What's old is ....
According to the preview by Phil Askey at
http://www.dpreview.com/articles/olympuse330/
"The E-330 achieves live view in one of two ways; in A Mode ('Full-time live view') the mirror stays in place and you can continue to use the viewfinder, the live view image is produced using a small secondary CCD sensor in the viewfinder chamber (as suggested by me five years ago). In B Mode ('Macro live view') the mirror flips up, " [actually, to the left, MW] "the shutter opens and the live view is provided by the E-330's unique 'Live MOS' sensor."
According to the preview by jeff Keller at
http://www.dcresource.com/reviews/olympus/e330-review/index.shtml
"The quality of the view depends on what live view mode you're in. In the everyday 'A mode', the quality is decent, but not as good as you'd find on most compact digicams (including the Stylus 800 from which the secondary CCD comes). Things just seem darker and grainier than I would've expected, especially in lower light conditions. The view in 'B mode' is much brighter and sharper, but as I stated at the beginning of the review, it's only for manual focusing. For brightening things up you can turn on the Live View Boost feature, which does make things easier to see. However, the view flickers and is quite grainy, at least on my pre-production camera."
Hmm..... LCD view not as good as on most digicams, darker, grainier..... I hope Olympus fixes the grainy, flickering LCD when using Live Boost before shipments start. What about the optical viewfinder? Darker, according to the Olympus technical team interviewed here:
http://www.quesabesde.com/noticias/Olympus-E-330-Yoshiyuki-Nada,1_en_2256
"Could this new previewing system have any kind of impact on the brightness of the viewfinder?
Yes, the brightness of the optical viewfinder is slightly darker than in the E-300, but not so significant. Thanks to the combination of nine pixels on the second sensor, we can maintain the brightness of the view on the LCD."
I love the concept, but I remain concerned about the dimmer viewfinder for underwater use. Time will tell....