The first thing you'll notice on picking up the 45mm F2.8 macro is just how tiny it is. The lens is little bigger than Panasonic's 14-45mm kit zoom, remarkable for a 1:1 macro with image stabilization, but the font element is surprisingly small. The premium branding is subtle; the font used for the barrel markings is pure Leica, the '45' is in a deeper orange than is used on 'standard' Panasonic lenses, and the barrel is black not gray. The construction is lightweight (weighing in at just 7.9 oz / 225g) but reassuringly solid, similar in feel to the 20mm F1.7 Pancake, and the black paint finish perfectly matched to that on the GF1.
The lens is well laid out too; the focus ring is wide and beautifully smooth, and the two switches for the image stabilizer and the focus limiter are large and easy to use. The focus limiter is a welcome addition compared to the Olympus 50mm F2 macro, however macro enthusiasts may well be dismayed by the lack of any focus distance marking or reproduction scale. Focus is entirely internal so the lens stays the same length throughout its impressive distance range.
Somewhat disconcertingly the OIS unit audibly rattles around inside the barrel, and only locks in place when mounted on a powered-up camera (turn the camera off and it's free to move again). This behavior is not in fact limited to the 45mm (it's just what Panasonic's stabilized lenses do), but it's much more noticeable compared to the likes of the 14-45mm or 45-200mm kit zooms.
'Focus-by-wire' manual focus
The most unusual feature of this lens's operation is the focus-by-wire manual focus system, which drives the focusing group indirectly via the lens's autofocus motor. This has the advantage of allowing a very long manual focus travel, and therefore extremely precise focus - crucial for a macro lens.
However it's not all good news. The feel of the manual focus ring never changes, regardless of whether the camera is set to auto or manual focus (or even when the focus has reached the limits of its travel) and this lack of tactile feedback can be disconcerting. Compounding this is the fact that, with neither a focus scale nor a change of length on focusing, there's no visible feedback on the lens as to where it's currently focused (so no quick setting to approximately the right distance).
This leaves the camera's viewfinder as the only means of judging manual focus - not such a bad thing you may think, but if you normally have the camera set to automatically jump to magnified view on turning the focus ring, you can easily lose all sense of what the focus ring is actually doing (you simply can't tell from a blurred enlarged view whether you're bringing the image into, or out of focus). Personally I'd recommend turning off manual focus assist when shooting macro with this lens (it would be nice if Olympus or Panasonic gave us a 'one-touch' focus assist option).
On the camera
The 45mm macro is perhaps best matched to the 'faux DSLR' styled G1 and GH1 bodies, not only proportionally but functionally too (the articulated LCD is great for macro work at odd angles in the field). Despite its small size it's already looking a little bulky on the GF1 or E-P1 (and most certainly not pocketable), although it handles perfectly well on each. Controls are well-placed - the manual focus ring falls perfectly to your left thumb and forefinger, and the OIS and focus limiter switches are easily reached too.
Autofocus on the 45mm is generally pretty impressive. It's normally fast and decisive, and the motor is very quiet. It's not completely silent - there's a slight high-pitched whine to it - but it's noticeably quieter than the 20mm pancake and very close to the 14-45mm kit lens. It's also capable of continuous autofocus while recording movies, but in this mode it's driven relatively slowly and doesn't refocus anything like as quickly as the 14-45mm. Focus seems consistently accurate too, as we'd expect from a good contrast-detect system. However it does seem to miss focus and end up hunting a bit more than we're used to on Micro Four Thirds, especially in low light - so it's worth keeping an eye on the limiter switch and setting it when you're not shooting close-ups.
On Panasonic G-series models, the 45mm becomes capable of something that's simply not possible with any DSLR system - genuinely usable autofocus when shooting macros. These cameras allow you to choose an extremely small AF point and place it wherever you like within a large area of the frame (although not at the extreme borders). This means you can tell the camera to focus precisely where you want within your composition, and it will just do it without any fuss - it's a very useful tool indeed.
1) Panasonic 14-45mm and Olympus Zuiko Digital 50mm F2
To get a better idea of the tiny size of the 45mm, here it is in between Panasonic's diminutive 14-45mm kit zoom and the Olympus Zuiko Digital 50mm F2 macro mounted on the Micro Four Thirds adapter (see here for a similar comparison without the adapter). The petite size of the Leica macro is all the more extraordinary when you consider that it doesn't change length on focusing, in contrast to the Olympus which extends dramatically (picture here) yet only reaches 1:2 magnification as opposed to 1:1.
Compare the GF1 + 45mm combination to the Olympus 50mm on the E-620 and you can see that, while some of the benefits of the slim GF1 body are lost with a lens this size, it's still smaller and more portable than one of the most compact DSLR combinations on the market.
2) Canon EF 100mm F2.8 L IS USM
Where the Micro Four Thirds size advantage really does tell, of course, is in comparison to full frame systems. Here we're comparing it to Canon's new image-stabilized macro, the 100mm F2.8 L IS USM, which was announced just a day before the Panasonic. Even on the bulkier G1 body, the 45mm is tiny alongside the full-frame system. Of course we're not saying the quality obtainable from these two systems is identical, and Canon's new 'Hybrid Image Stabilization' promises to be more effective when shooting hand-held at close distances than conventional systems. However it's perhaps worth pointing out that if you're trying to capture the finest possible detail at 1:1 magnification, the G1's finer pixel-pitch sensor means it will handily out-resolve the 5D Mark II (although not the APS-C EOS 7D).
Lens body elements
|The 45mm macro features the Micro Four Thirds mount, currently compatible with cameras from Olympus and Panasonic. Communication with the camera is all-electronic, via the gold-plated contacts.
The lens mounts by aligning the red dot to that on the camera’s mount, and rotating clockwise to lock.
|The filter thread is 46mm (the same as on the 20mm F1.7), and does not rotate on focusing, which will be welcome to filter users. Surrounding it is a bayonet mount for the lens hood.|
|The Leica-inspired broad, rectangular H-ES045 hood gets 10 out of 10 for style, but quite a lot less for practicality. It's nowhere near as deep as it could be (and therefore probably less effective), and it can't be reversed back over the lens for storage.
If there's one consolation, it's that the hood is sufficiently broad to make removing and replacing the center-pinch lens cap easy enough.
|The manual focus ring is 15 mm wide, and extremely smooth and well-damped. The focus-by-wire system allows a remarkably generous travel from infinity to closest focus.|
|Two large positive switches on the side of the barrel allow you to limit the near focus to 0.5m, and turn the optical stabilization on and off.
In a slight stylistic faux pas, the large font used to label the switch panel doesn't match squared-off 'Leica' font used elsewhere on the lens barrel.
Reported aperture vs focal length
The lens allows apertures from F2.8 to F22 to be selected.