I have been reviewing and editing photos from the local zoo trip yesterday. On the day I had the 4/3 70-300mm on the EM-1 for the outdoor photos. For those that don't know the lens it is a F4 to F5.6 unit and part of the 4/3 standard range. It can take a surprising good photo and I have a few littering in some image threads. I spent some time deliberately shooting in the 100->200 range so I could have some comparison images for the 40-150 2.8. For the first couple hundred images I kept seeing how the 2.8 could have helped big time but then I got to a set of photos of the little penguins. These were all shot wide open from 4.5 to 5.6 depending on zoom level. Now the bit that got me was that on a number of shots the eye's were in focus yet the beak was out of focus less than 2 inches away despite the @ F5 aperture, I shuddered to think just how thin the dof would have been with the 40-150 2.8 or conversely how many photos I would have thrown away because I didn't stop down at that point. Now as I type this it raises a thought that the lenses with large apertures force you to think about the aperture your using and actually stop down as required, so unless your using P mode you have to think in advance and maybe preview the dof as needed. It also made me think that for a majority of people (even myself maybe) the 40-150 2.8 may well be excess to need though no doubt for the pro and serious enthusiast it appears to be a must have :smile: I'll post a couple images to illustrate the point very soon, just on the wrong computer at the moment.