The lens is fairly compact, with a 37mm front lens thread, and is significantly smaller than the other 45mm prime lens, the Panasonic-Leica 45mm f/2.8 1:1 macro lens. They are shown below:
Panasonic 45mm f/2.8 macro (left), Olympus 45mm f/1.8 (right)
Sadly, the lens does not come with a hood. You can buy a hood from Olympus, which is rather expensive, and fits into the bayonet threads under the silver front ring. I chose to buy a collapsible rubber hood with a 37mm screw thread. It cost around US$12 including shipment from China. In the picture below, I have removed the silver ring, revealing the black bayonet mount, and mounted the third party hood:
As far as I can tell, the lens itself is constructed out of plastic materials, has a metal mount, and has polished metal exterior. I know this is a subjective thing, but my opinion is that the appearance is very cheesy. I would have preferred a matte black plastic exterior, which I think is better. I'm looking into ways of making the lens less obtrusive, perhaps using black electrical tape to cover the metal surfaces is a good idea?
Just like most Micro Four Thirds lenses, the Olympus 45mm f/1.8 has internal focus. This means that there are no moving mechanisms on the outside, beyond the focus ring, and the lens feels solid. This is in contrary to the Lumix G 20mm f/1.7 pancake lens, which has a traditional focus mechanism which moves the entire lens assembly back and forth, making the focus relatively noisy and slow.
The focus ring moves smoothly, and feels like good quality. I could have wished for a rubberized focus ring, though, as the metal is not as ergonomic to use. But I don't see myself using the focus ring a lot anyway, as the autofocus works well.
The autofocus is very fast, and virtually noiseless. I have compared the focus speed with the Panasonic-Leica 45mm f/2.8 macro lens on a Panasonic GH2 camera, and found that in generous lightning, the Olympus lens focused a tad bit faster. In low light, though, the Panasonic lens focused faster, which surprised me.
The focus timings of the Olympus lens in good light are a little bit slower than the kit zoom lenses. See the comparison here for some reference numbers. However, keep in mind that the Olympus 45mm f/1.8 requires a lot more focus accuracy than a kit zoom lens at 42mm f/5.6, due to the much larger aperture. Considering this, I think the Olympus 45mm f/1.8 focus timings are very respectable.
When it comes to autofocus performance during video recording, I've found the lens to be comparable with the Panasonic-Leica 45mm f/2.8, which is to say, not very good. With a moving scene, it can take some seconds before the lens regains focus during video capture, which can be very annoying. But I suspect this is much due to the camera, and that future advances in CDAF and image processing will make continuous autofocus better in time.
The minimum focus distance is 0.5m. While this does not sound very impressive, when comparing with other portrait lenses, it is in fact rather good. The classic 85mm f/1.2-1.8 portrait lenses generally have a close focusing distance of 0.8-0.9m. If used for a headshot portrait, this makes sense, since around 1 meter is the distance needed to fill the head into the frame at this field of view. Nikon's newly released Nikkor 85mm f/1.8G portrait prime lens has a close focusing distance of 0.8m, which is not as good as the Olympus lens.
The lens features no optical image stabilization at all, just like all other Olympus lenses. When used on an Olympus camera, you get the sensor shift image stabilization, which is effective for stills capture. During video capture, though, there is only digital image stabilization available, which I am told does not work too well.
On the other hand, the Olympus OM-D E-M5 camera, launched early 2012, does provide sensor shift image stabilization during video recording. Using this technology, perhaps this lens can be useful for video on newer Olympus cameras.
On a Panasonic camera, there is no image stabilization at all. So for still images, you should try to use a shutter speed of 1/100s or faster to be fairly sure to avoid camera shake when handholding the camera. For video recording on Panasonic cameras, there is no image stabilization available, and it is quite simply difficult to handhold the camera stably during video capture.
In this example, I have recorded a video with the Panasonic GH2 and the Olympus 45mm f/1.8 lens. Believe it or not, but I am doing my best to hold the camera stably, holding the viewfinder towards my eye. To my defense, I can say that I had just gotten off my bicycle during my daily commute to work, which could explain my somewhat shaky hands:
I have made some image quality comparisons with the Panasonic-Leica 45mm f/2.8 (PL45) here. It must be said that all the comparisons are not optimal, since the focus point is not always exactly the same. However, I think this shows that the Olympus lens does not have any significant vignetting.
The Olympus lens does, however, have some Chromatic Aberration (CA) artifacts when the aperture is larger than f/2.8. I also think that the PL45 performs better at f/2.8 in terms of image quality, although the differences are small.
I have tried to do another image quality comparison. To avoid the problem of different focus distances, I chose a subject that was fairly flat, a car registration plate. I focused on the "P" in both cases. The focus distance is about 1 meter, which corresponds to a headshot portrait distance for this focal length. Here is the whole scene, the images are rescaled and sharpened:
PL45 @ f/2.8
Olympus 45 @ f/1.8
Looking at 100% crops to better evaluate the sharpness, I find this:
From the left middle part:
From the right hand lower corner:
In this comparison, it looks like the sharpness is comparable in the centre of the image, while the PL45 performs somewhat worse in the corner. I would like to add that this comparison is not as challenging for the lenses as my previous one was. The examples with trees rendered against a bright sky are much more challenging for the lenses, due to the high contrast.
All in all, I think the image quality is quite good. There is little vignetting, some CAs at apertures larger than f/2.8, and the sharpness is quite respectable for a large aperture lens.
My sharpness comparison also included some bokeh examples. As far as I can see, the lens does not have any problems with the bokeh. It renders the background nicely blurred when it is out of focus, at all apertures. And out of focus highlights are even and rounded.
One thing to look out for, though, is that the aperture diaphragm blades are not as rounded as on the Panasonic-Leica 45mm f/2.8 1:1 macro lens. This means that when stopped down, the out of focus highlights get a slightly more jagged edge.
Here is yet another bokeh study, compared with the Lumix G 20mm f/1.7 and Sigma 30mm f/2.8 lenses.
Here is an example image:
I used the Panasonic GH2, and the image parameters are: ISO 160, f/2, 1/10s. I focused on the front wheel. The camera was handhold, without any support. How come the image is sharp, with a shutter speed of 1/10s? Because I also used the onboard camera flash. The flash is very quick, and freezes all movement. However, it has a fairly short effective distance, so only the front part of the truck is lit by the flash. The rear part is lit by ambient light, and the tail lights from a passing car.
Since the rear part of the car is out of focus anyway, a bit of blurring due to camera shake during the 1/10s shutter time doesn't matter.
Compared with the Panasonic-Leica 45mm f/2.8 1:1 macro
So, which 45mm prime lens should you get? The Olympus M.Zuiko Digital 45mm f/1.8 (MZD45) or the Panasonic-Leica 45mm f/2.8 1:1 macro (PL45)? If you want to take macro images, there is only one choice, the PL45. However, if you are on a tighter budget for a macro lens, you could also consider the Olympus 35mm f/3.5 1:1 macro lens (Four Thirds standard, not Micro Four Thirds). For this lens, you will also need an adapter, e.g., the Panasonic DMW-MA1 or the Olympus MMF1/MMF2. This combination will have poor autofocus performance on Micro Four Thirds cameras, but some people prefer manual focus for macro use anyway.
If you are looking for a traditional portrait prime lens capable of selective focus and good bokeh qualities, I think the MZD45 makes the most sense, since it has the largest aperture. However, I personally think that the f/2.8 aperture of the PL45 lens is sufficient for a portrait, given that you can plan the background a bit. So either lens should get the job done most of the time, in my opinion.
For video use, the Optical Image Stabilization (OIS) of the PL45 comes handy. Holding a 45mm lens stably while recording video is not easy, and the OIS does give some help. So if you intend to use the lens for video as well, you may want to consider buying the most expensive of the two, the PL45.
This lens comes with a fairly reasonable price tag, especially in Europe, which makes it a must buy lens for people interested in portrait photography and selective focus.
The image quality is good, and the focus speed is fast. The lens is not so well suited for video recording, due to the lack of optical image stabilization. Also, when recording videos, it can be a good idea to prefocus, and then turn off autofocus before starting the recording. The continuous autofocus performance during video recording is not so good, especially in poor lightning.