Nikon D90 or Pentax k20d or Cannon 50d

[Sushigaijin]

who knows what the future holds? Personally I think that all of the formats will diverge and mature - FF for fine art pros, APS and 4/3 for hobbyists and working pros. The differences will become more severe as technology improves, and they can all refine and develop their strengths.

Now I see what you are saying about sweet spots - FF lenses will have a larger sweet spot on crop sensors. Agreed. However, some manufacturer's digital specific lenses create finer images, all things equal. The ZD lenses correct incidence angle so that light strikes the sensor at the optimum angle. They are engineered for corner to corner sharpness and brightness. Sure the sensor lags behind the APS sensors, but the lenses are superior to 90% of the other stuff out there.

Canikon could really improve their lines by making digital specific superior lenses. it's just a matter of building lenses for the format rather than building a format that works with out-of-date lenses. A FF camera with a digital-corrected FF lens would be killer - but that's gunna be one huge and heavy lens! They are going to have to consider things like this if FF sensors are going to be built to have more resolution - the lenses are already showing flaws on the sensors we have today! The benefit of a large sensor is only as good as it's lens! I see lens quality as the limiting factor for FF format...

[Dougjgreen]

Now I see what you are saying about sweet spots - FF lenses will have a larger sweet spot on crop sensors. Agreed. However, some manufacturer's digital specific lenses create finer images, all things equal. The ZD lenses correct incidence angle so that light strikes the sensor at the optimum angle. They are engineered for corner to corner sharpness and brightness. Sure the sensor lags behind the APS sensors, but the lenses are superior to 90% of the other stuff out there.

Some are, most aren't. I'd go so far as to say that, other than the 7-14, 9-18, 11-22, 12-60, and 14-50, and 25mm pancake, none of the other Olympus lenses do anything special in this regard. Some of the others, like the 35-100, and 55-200 are very good lenses, but there is nothing unique in their designs to make them telecentric - other than the fact that the format itself requires a smaller image circle, thus causing more direct angle of incidence. And other super-wide lenses that use retrofocus designs from other manufacturers are also designed this way - it's not at all unique to Olympus.

Canikon could really improve their lines by making digital specific superior lenses. it's just a matter of building lenses for the format rather than building a format that works with out-of-date lenses. A FF camera with a digital-corrected FF lens would be killer - but that's gunna be one huge and heavy lens! They are going to have to consider things like this if FF sensors are going to be built to have more resolution - the lenses are already showing flaws on the sensors we have today! The benefit of a large sensor is only as good as it's lens! I see lens quality as the limiting factor for FF format...

It is true that one thing Olympus had going for it was that they actually NEEDED to design many of their lenses, especially the shorter ones, from scratch, because they started with a new format. Canon and Nikon did take a short cut initially, in that they used the same lens mount as their film cameras. But, for the smaller sensor cameras, they too needed to design new wide angles, and in doing so, they did the same things that Olympus did as far as telecentricity. And Olympus also pulled many of their longer telephoto designs off the shelf from 35mm land - some were their own, and some were licensed from partners like Sigma. The only thing that makes those lenses more telecentric than the ones for Nikon and Canon is that Olympus crops the image circle even tighter for their smaller sensor.