That really depends on the platform. If you're willing to go with a higher crop factor you will see real world size reductions in the lens. For example, compar

That really depends on the platform. If you're willing to go with a higher crop factor you will see real world size reductions in the lens. For example, compare the size of the Panasonic M43 35-100/2.8 to the Canon 70-200/2.8 or Canon 70-200/4.0 http://camerasize.com/compact/#333.7,333.294,521.366,ha,t http://camerasize.com/compact/#333.7,333.294,521.366,ha,t There's a noticeable reduction in size and weight with the M43 gear if you're OK with the compromises of using a crop sensor. I used to have an APS-C DSLR and carried a few lenses with me on trips. My main system now is Nikon 1 and in the same space in my bag that my DSLR and lenses used to take, I can put two bodies and five lenses. While I know that many people consider the Nikon 1 system a joke, I chose it because it works very well for my specific needs (I also have some M43 gear but I still prefer my N1 gear because of the size). Obviously, I wouldn't recommend it to most people, since their needs don't necessarily line up with mine.