Sigma 18-50mm f/3.5-5.6 DC Reviews

I bought this lens when I purchased my Pentax *istD three years ago as a package with the 55-200 DC zoom in the same box. Of the two,the longer zoom is the better choice,though this one was quite adequate as a short zoom for my Pentax camera for a year till they came with the 18-55 kit lens. I would evaluate the lens as adequate,far from outstanding.

For the price paid I have no complaints. I use it with my 30D. I wanted a very light zoom, wide to normal, and I mostly use the 18-35 range of the lense, and I should say I use it as a prime each time. I place the zoom ring either at 18mm or at about 22 mm, and go out to take pictures. I don't change the focal distance during walking around, I have the discipline to do this. This lens was what I was looking for in terms of weight and flexibility, but i wasn't expecting much more. So I was very much surprised when I discovered that when stopped down to say f5.6 or f8.0, the lens is more than sharp enough. There is extreme CA in the edges (purple fringing) and geometrical aberrations at 18mm, but this doesn't bother me so much. The colors are warm overall, and the lens is worth every cent you pay. Due to its weight and non obtrusiveness, it is more versatile for taking pictures of people on the street than the very much classier Tamron 17-50, f2.8. So, this lens has a place on my camera (and not only in my bag).

I've had this lens almost a year and can say that for a $90 lens it fulfills its expectations. Wide open at f3.5 the sharpness is not that great, but if you can stop it down a few stops it does an admirable job. Non-moving subjects in low light (buildings at night, a Christmas tree lit in a darkened room) look great stopped down to f12 or f14 but sharpness often suffers as the aperture gets much smaller than that. Two filters is max for this lens, and the included lens hood does no good with both filters on. Weight and feel are both pretty decent, and I have not had any problems or quality issues with it at all.