10 out of 10 points and recommendedCheap, light, great image qualityNeeds adapter to go to 1:1
I bought this lens used on eBay when I was looking for a cheap macro lens and I have been very happy with it. It has great image quality, the pictures come out sharp and with very good contrast.reviewed December 13th, 2006 (purchased for $90)
The lens is basically built around a main barrel that extends out to quite a bit when focusing at macro distances. The barrel and the lens are very light, but that also makes the micro-motor focusing quick enough for most purposes. Overall build is quite solid and can take a few knocks, although it doesn't give the same quality feel as an L lens.
The 1:1 adapter that comes with it is basically a dedicated dioptre lens that mounts on the filter thread. With it one can only focus in the near to 1:1 range and focus hunting becomes more of a problem. But at that range manual focusing is required most of the time. The sharpness and contrast degrade a bit when using the 1:1 adapter, but I still find it adequate. On the plus side you can use the adapter on other lenses too (e.g. on a 50mm lens, paired with a thread adapter).
Overall, this lens is great value for money and excellent for a starter in Macro photography or for someone on a budget. I won't be selling mine for a while.
9 out of 10 points and recommendedSmall, light, excellent zoom range for both full-frame and cropped digitalSoft corners at wide aperture, some flare problems, zoom creep
I bought this lens to use on an EOS film camera but I am now also using it on a 400D.reviewed December 14th, 2006
On a full-frame camera it makes in my opinion the best walk-around zoom you can buy if you don't have the cash or muscle for the 24-70L. It's light, it's got a very flexible range (I love 24mm), USM and the image quality is very good.
On a digital camera it still makes a useful 37-135mm general purpose lens and I use it almost daily.
I noticed softer corners at wide apertures on 35mm slides, especially towards the wide angle, but to be frank these were not real situations - most of the time at wide angle one has to stop down a bit to get appropriate DOF. It also shows a bit of flare/lost contrast when shooting against the light - probably due to the wider glass elements.
Build-wise there is some zoom creep if pointed downwards - wish it was a bit more damped. Also, I wish the zoom turn would be a bit longer, it takes a very small rotation to go from 24mm to 35mm for instance.
Otherwise it's a lens I highly recommend and I certainly advise against the 28-105 alternative which is less useful if you are contemplating a crop-sensor digital camera.