I, like many people, I was lured into buying a m4/3 camera because of the potential to adapt virtually any kind of lens for its use - especially those cheap, ultra-fast C-mounts. My E-P2 will be arriving in the mail tomorrow, and I started doing research about what "fun" lenses I could get. It wasn't until a couple days ago that I realized that C-mount lenses will almost invariably have serious vignetting (and/or other) issues, in addition to the potential adapter incompatibility issues that I already expected. And although the E-P2 will be my "fun lens experimentation" camera, I'm sure that the novelty of an ultra-fast lens will quickly wear off if the lens in question only covers 85% of the sensor and/or is soft to the point of looking like it's covered in butter. Could someone please provide some suggestions for any of the following: 1) What kinds of potentially interesting lenses to avoid entirely. E.g., I know that D-mounts are probably no good, having been designed for 8mm, and that Switar RX lenses are also questionable, not having been designed for photography. 2) Who (maybe on eBay or else on these/other forums) does goods jobs with modified lenses. E.g., I've seen sellers jieying-usa and ed_lee83 sell some modified ultra-fast C-mounts 3) Which fairly affordable ultra-fast lenses, f/1.1 or better, CAN actually produce 100% sensor coverage (light vignetting OK, but not to the point of always having completely black corners) and not completely and utterly soft photos 4) Which fairly affordable ultra-wide lenses are available and have been successfully used with m4/3 without extreme vignetting. This thread is great, but my goal for an ultra-wide is not necessarily a huge aperture... doesn't hurt, of course And I also have a question that's not quite in the tip/suggestion category: 5) When the Noktor f/0.95 lens was announced, I noticed that the online community was quick to point out that they are likely re-branded C-mount industrial lenses, which are already sold under DO Industries or other brands. Has anyone found a significantly cheaper source of those lenses, though? I've seen the industrial ones on eBay for roughly the same price as the m4/3 Noktor. Moreover, would those lenses + C-mount-to-m4/3 adapters even produce good results? IMO, it's possible that the lenses were slightly modified to get them ready for recreational use, in the process of being rebranded. *EDIT: Woops, corrected to Noktor* I have a feeling that I'll end up with a Nokton 25mm f/0.95, eventually, if I can find it for ~$800. And I think that the size and quality of the Nokton 35mm or 40mm f/1.4's MIGHT just justify their ~$500 price tags, as well. That said, there are some proven ~35/1.4 and ~50/1.2 lenses in OM, Canon FD, or other mounts that can often be found on eBay for ~$300 or less, while a lot of the 50/1.4 lenses are outright bargains. And I do already have an OM 50/1.4. But if there are some fun, fast C-mounts that can be gotten for relatively cheap, I'd want to play around with them before spending significant sums of money. So that I'm not a total leech, here are a few links that I've found useful in my research: 25mm c-mount vignetting shootout good c-mount adapter discussion Using Ultra-Fast Lenses on DSLR Cameras - not completely relevant for m4/3, but related All of the above also have links or mentions of other threads/articles that are useful. Thanks for your input!