[Klaus]

If we compare more moderate designs like

Oly 12-60/2.8-4 (FT) vs Canon 15-85/3.5-5.6 (APS-C)

or

Oly 50-200/2.8-3.5 to Pentax 60-250/4 (APS-C)



They are pretty much the same in terms of body specs (1 f-stop advantage for APS-C vs MFT/FT).



The 14-35 & 35-100 are probably not too valid for a comparison because the design efforts are on a different level. The pricing is very different as well.









[quote name='Brightcolours' timestamp='1314655060' post='11154']

The size and especially weight of the faster Olympus lenses is usually quite a bit bigger/higher than FF equivalents. Your Pentax example above shows that, but also comparing a Canon EF 70-200mm f4 L IS USM with the Olympus 35-100mm f2, for instance, shows this.

In case of the 35-100mm f2, it is mainly due to design choices. The design basically is a 70-200mm (f4?) lens, with a 0.5x wide angle converter in front of it.

Olympus 35-100mm f2:



Canon 70-200mm f4 L IS::



Canon in blue overlayed on Olympus in red:

[ATTACHMENT NOT FOUND]



Olympus 35-100 f2 size/weight: 96mm x 213.5mm / 1650 grams

Canon 70-200mm f4 size/weight: 76mm x 172mm /760 grams



If you take equivalent lenses, 4/3rds lenses usually are heavier and bigger. The lenses that are smaller usually have no equivalents on full frame or APS-C, as their maximum apparent apertures for the used FOV are very small.



Still, if you do not care about smaller apertures, you can put together a relatively small kit, of course.

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