Hello everyone,
I am an amateur photographer and recently purchased my E-510 with the
14-42mm kit lens.
Here are some thoughts to keep you budget under $500 that give you different things to think about:
1) FL-36 flash + 35mm macro lens -- the external flash can give you a lot better pictures than the pop-up flash and provides a red focus assist light that is easier on your subjects. The 35mm macro lens would let you photograph small things like flowers. I suspect the bokeh (quality of the unfocussed area) of the 35mm might be nicer than the 14-42mm for portraits.
2) FL-36 flash + 40-150mm lens -- same flash as #1 but the 14-150mm lens gives you more telephoto reach. Also a lot of people prefer using a telephoto lens for portraits since it blurs the background more, but you do have to stand back further.
3) 50mm lens -- No zoom on the lens, but it is 3 stops faster in terms of speed than your 14-42mm lens is at 42mm (f/5.6). The 3 stops means you can shoot a scene at ISO 100 what you would need to shoot at ISO 800 with the 14-42mm. As a macro lens, it will also let you photograph small things like flowers. The downside is the depth of field of f/2 is much smaller than you get at f/5.6. Sometimes you want a small depth of field (usually in portraits), and sometimes you want a larger depth of field (group shots to get everybody in focus). The bokeh of the 50mm is the best of the 4 lenses I own, and a lot of people like it for a portrait lens. I always tell people when thinking about a prime lens, to spend some time shooting as near the focal length as possible with your current lens, and not use the zoom on the lens (zoom with your feet) to get a sense of whether it would work with your style. Because it is a macro lens, it doesn't focus all that fast -- it is ok for focusing on people if they aren't moving too fast, but fast kids might be gone before the lens focuses.
4) 11-22mm lens -- This is somewhat over your budget, but it gives you a wider angle of view which you might need for architecture. It also has less distortion than many of the standard lenses, which again is very useful for architecture, since you won't need to use PP to straighten lines as much. It is faster than your kit lens, so it would give you some more headroom in low light shots. I would suspect that like the 14-54mm, the lens will cause a shadow when you use the pop-up flash, but just use the 14-42mm for the flash (also at wide angle, I would imagine the pop-up flash wouldn't be able to illuminate the corners).
5) 14-54mm lens -- this lens would pretty much replace your existing lens, except when you use the pop-up flash (maybe consider selling the 14-42mm and try to buy a FL-36 with the proceeds). I believe the 14-54mm has less distortion than the 14-42mm, and it is somewhat faster. I sold my 14-42mm, so I don't have much in terms of direct comparison. Because this pretty much replaces the lens, it doesn't give you much new range other than some telephoto, and the ability to focus much closer.
6) Sigma 30mm f/1.4 or 24mm f/1.8 -- These are prime lenses from Sigma that are faster than your kit lens. I've heard rumors that they are pretty soft until you get down to f/2.8, which means they don't give you as much bang for the buck as you might expect. I would suggest looking at shots with these lenses to see for yourself what to expect.
7) Olympus 50-200mm (non SWD) -- This gives you a lot more telephoto range, but it is large and heavy. It is also over your budget, but maybe you can find a used one as people upgrade to the new 50-200mm SWD lens. The new 50-200m SWD lens is way over your budget. You will have to hunt around for this, because it is down to dealers selling existing stock. This is my second favorite lens after the 14-54mm.
8) FL-50 flash -- this gives you a lot more power than the FL-36 and faster recharge time, but it does pretty much eat your whole budget.
9) FL-36 flash + 25mm pancake lens -- this lens was just announced, so nobody knows how it performs. At f/2.8, it will be a little faster than your 14-42mm. It won't be available for another month or so.
10) Olympus 70-300mm -- this lens would give you a lot more zoom, but you will have a hole between 42mm and 70mm in terms of your range.
11) Forthcoming Olympus wide angle lens -- this lens is on the roadmap but hasn't been announced yet, so what the specs are, what price it will retail for, when it will show up in stores, and what the images it takes look like are anybody guess at this point.