Thoughts on MP, DR and 4/3rds lens system
I learnt long time ago that in terms of photo equipment what really mattered is glass first, and film second.
The camera used to be that thing that connect the glass with the film. I've seen incredible photos shot with crappy cameras, as well as I've also seen gorgeous photos shot with lenses scratched and finger smeared.
In the end is the photographer who made the difference and who does STILL makes the difference.
In the digital age there is not much difference, except that the camera IS now the film (for sure not the compact flash card). The camera can also be a digital portable dark room, an equivalent of the one you have on your computer in your studio.
And like film, your camera also dictates what resolution your photos will be. As you don't shoot with 35mm format and expect it to look like a large format (well color could but resolution wont) you should have similar expectations for digital.
Similarly, the 4/3rds system will ALWAYS lags behind bigger sensors in terms of resolution, since the maximum pixel density available at any given time should be always roughly the same for all sensors.
If you need the best resolution currently available then go for a medium or large format: the 4/3rds (or any APS and similar size) is not for you.
The 4/3rds is for you when you don't care if you get few pixels more than the rest of the crop (pardon the pun) but if it gives you photos as good as you want them.
It is also for you if you believe in a near telecentric lens system which is designed for sensors instead of emulsion, and you believe that resolution (or mp) is just secondary to color reproduction and quick use, which allows more opportunity to capture that image you have in front of you.
This doesn't mean wouldn't mind more resolution in a 4/3rds camera: I do a lot of panoramas and I can always use some extra detail... maybe... sometimes I did get some pictures where I wished I had some more mp or less grain for that matter: detail is detail and after all the megapixels race is similar to the one we had for the last century over faster emulsions with smaller silver grain.
4/3rds aren't medium format, it will never be: the choice to be smaller sensor system has pro and cons: but in the end if 4/3rds gives you what you NEED, then it is what you need for the rest of your photographic career (or till you change your mind because you read it in a forum).
That's about resolution, but what about noise and Dynamic Range? Does the 4/3rds have a disadvantage there?
Sensors do have an enormous disadvantage there, but all of them are and not just 4/3rds IF compared to film. We are just not there with film DR yet, at least not with small DSLR's.
Right now we are stuck on a technological limbo: our techno substitute for film has some clear advantages, but it does lacks the dynamic range of the best emulsions. The best DSLR's have a DR with measured range of 7-9 stops, compared to 13-14 stops of a good film. Even considering that 1-2 stops software highlights recovery is possible it is a far cry from film, and you need to bracket pictures to get more DR with all the issues that that implies: mainly a complicated workflow and moving objects problems.
Of course the DR range numbers above are an approximated sample, as it is very difficult to compare the dynamic range of a sensor against film: sensor records light in a linear progression while film is logarithmic. Also, sensor dynamic range varies since the noise in the dark areas increases with heat.
The big difference is that emulsion stores a lot of light information on the extreme latitude of the exposures which gives you an image that has good color information even in very bright headlights. For that very reason film highlight looks gorgeous, way better than DSLR sensors. For photographers that share that statement it's easier to expose high contrast scenes with film than digital, unless you can afford a phase one... This is by the way also the reason why a lot of film makers still shoot movies on film.
I can get nice highlights from a DSLR, using bracketing and Photoshop, but a sensor lower noise would allows less bracketing (2 stops = 1 bracket) and less processing and therefore more shooting: more DR is something I NEED now, so I do work around the technological limitation of today's sensors by using bracketing and I do end getting what I WANT. Sometimes.
