My first L-series lens was the 24-70mm
, and I thought it was amazing. The 100mm f/2.8L Macro IS USM blows it out of the water as far as image quality is concerned. It's like experiencing that wonderful "introduction to L-quality" moment all over again.
The combination of prime optics and macro magnification mean that this lens gives pin sharp details at incredible scales. I really cannot stress enough just how good the detail resolution is at 1:1 magnification. I use a 7D and was expecting some loss of resolution due to the cropped sensor, but it is simply not apparent in full scale images. This lens is really fun to find uses for and it's kinda hard to keep it off the camera.
I can assure you that portraits from this lens are first class, especially when used in conjunction with flash bounced off a white ceiling. They are light, airy, and natural-looking. The focused areas are both razor sharp and finely detailed whereas bokeh is smooth and soft. Absolutely spot on! It can be a bit long for comfort on a cropped camera body but it is well worth the extra leg exercise. Using it for portraits and candids has given me an idea as to why people rave so much about the 135mm f/2L.
One area where this lens lacks somewhat is in its focus locking; it can sometimes seek a little, focus off-target, then lock on after a second. This means it is pretty poor at AF tracking - even when using AI Servo in anything less than bright light. Using the proper setting on the autofocus distance limiter is pretty much essential for most types of shot.
I use a Gretag-Macbeth colour chart to confirm colours with my camera/lens combinations and correct any drift. This has shown that of all the lenses I own the 100mm macro is the one which most consistently reproduces accurate colours. It has also shown that the colours most likely to drift with this lens are oranges and middle blues - of particular relevance when photographing insects, flowers, etc.
Unlike other black L-series lenses the main body is made from engineering grade plastic rather than metal. It remains very tough and robust, but is much lighter than it should be as a result. It's also weather resistant like much of the L range. The serial number of each lens is engraved on the metal docking ring which connects to the camera, as well as a date code which records when and where the lens was manufactured.
Because of the ring USM system, focusing is really quiet, which helps when taking close-up shots of critters. Full time manual (FTM) focus is enabled. The front does not rotate, and all focusing is internal. Minimum focusing distance is just under a foot (0.3m). The maximum magnification of 1x is increased to 1.17x with Extension Tube EF 12
and 1.37x with Extension Tube EF 25
. The lens is not compatible with either the 1.4x or 2x Mk II extenders.
For most people the decision as to whether or not to buy the L-series version of this lens will come down to the Hybrid Image Stabilisation. It becomes a bit less useful as magnification approaches 1:1, only giving the full four stops of improvement at 1:5 magnification and beyond. Improvement at 1x magnification is two stops at most, so if you only plan on using the lens for life size macro shots, you might choose not to pay out a couple of hundred quid extra for IS.
If you are also going to be using the lens for portraits and so forth, the IS will certainly pay dividends. HOWEVER, please don't take away the idea that the IS is useless for macro work; it helps stabilise the image in the viewfinder/LCD which obviously helps a lot. One last thing to note about the IS is that the 100mm Macro uses the Hybrid Image Stabilisation system which natively supports a kind of "Z-axis" stabilisation. At short focusing distances this can compensate for shift movements between lens and subject, as well as the angular movements that conventional IS corrects. This is very useful indeed for hand-held macro work. HIS really comes into its own when you are trying to capture swaying plants, or insects clinging onto stems etc. So it's not necessarily all about the additional stops!