I have an Olympus OMD E-M5 and a Panasonic/Leica 25 mm f/1.4. I love both of them, and together, they take care of 80-90% of my shooting. When i want to get tighter than normal, i also have a Sigma 60 mm f/2.8, which i also love. When i want to get wider than normal, i'm in a bit of trouble. All i have is the Olympus 12-50 mm f/3.5-6.3 kit zoom which came with the E-M5. This is a decent little lens, but the fact is that the performance is nowhere near that of the PL25 mm - as well as being considerably slower, if i make side-by-side comparison shots, i see a lot less detail with the O12-50. Plus, it's sufficiently bigger that it's more of a pain to carry and use (although still miles better than the equivalents on a full-size DSLR!). Given the two primes i have, the only thing i use the O12-50 for is wide-angle shots. And the occasional macro shot, but i only do those because i can. I wonder if there is a better option here. Now, obviously two much better options would be (a) buy a good wide-angle prime, like the Olympus 12 mm f/2.0, or (b) buy a good short zoom, like the Olympus 12-40 f/2.8. However, both of those are rather expensive. The cheapest whole-new-lens option would be to buy a Panasonic 14 mm f/2.5 - that costs something like 120 GBP new, maybe a bit less second-hand. I have no idea how it stacks up against either the PL25 or the O12-50. So what about getting a wide-angle converter lens? There are quite a few of these available, so for the sake of argument, let's consider the one from Photojojo (or if not that, some other high quality wide angle converter lens). This costs 50 USD, and would require a 2 GBP step-down ring to fit on the 46 mm thread of my PL25 (or S60, as it happens). It's cheap, it's compact to carry, and i would be using the lovely PL25 lens to do the heavy optical lifting. Plus, it's one of the two-part types that doubles as a macro adaptor, so i can even keep taking macro shots. However, i realise that adding a random lump of glass to the front of my lens does not come without downsides. Barrel distortion? Vignetting? Loss of the all-important fine detail across the field? Sure. Which leads me to the crucial question: would i expect the deleterious effects of the adapter to drag the image quality of the PL25 down to below that of the O12-50, or would this combination be a net win?