[Brightcolours]

[quote name='Klaus' timestamp='1314651105' post='11151']

If we consider

- the same FoV

- the same DoF

- the same "system" speed

the lens size and weight will be essentially the same (plus/minus a little).



Take e.g.

Olympus 150/2: 100x150mm • 1610g

Pentax 300/4: 83x184mm • 1070g





(the Pentax is a full format lens actually. I took it as a reference over the Canon/Nikkor because it is a newer design)



MFT lenses are smaller because they sacrifice DoF.



There is nothing wrong with this per se. You can consider me to be either a MFT or NEX user after all so I'm not stinker who has negatives stakes against the system. But at the end of the day we need to be realistic.

[/quote]

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.