My back yard is the Pacific North-West rain forest and that’s where I spend most of my leisure time; lately with the EM-5/ 12-50 kit I bought a few months back. I want to upgrade the lens to get better results in the dank low light/ mottled light environment. I’d like to get the most bang for around $800. I’ve broken down my options to the following; a) Sell my 12-50 and buy a 12-40 2.8. My big hesitation is that the 2.8 still won’t give great results in the gloom. Pluses: zoom versatility, weather sealed (we get a lot of rain, fog, mist). b) Keep my 12-50 and buy one of the 1.8 lenses leaning to the 75mm. Here my hesitation is no weather sealing and being limited to one focal length. I don’t know – maybe the 75 is too long in the gloom and I should be considering a 25 or 45mm @ 1.8 instead. I’d like to be able to capture moving targets in the environment such as mountain biking buddies, the dogs etc. Again; I keep going back and forth from the reported sharpness/performance of the 75 vs the versatility/weather sealing of the 12-40. I’d really appreciate advice that any of you can throw to help guide a rookie.