Lens Test Panasonic Lumix 45-150mm f4-5.6 OIS

Introduction   The 45-150mm is Panasonic's third midrange zoom lens for the Micro Four Thirds System.  First came the45-200mm OIS. I bought and used  two of these over the years and found both to be very good performers in the 45-100mm focal length range. But towards the 200mm focal length they lost contrast, sharpness and focus accuracy with distant subjects. In addition the 45-200mm is larger and twice the weight of the new 45-150mm. Next up was the 45-175mm power zoom lens which appears to have been intended mainly for video applications. I bought one of these last year and had to return it to the vendor. It produced severe blurring with double imaging in the 1/20-1/200sec shutter speed range with OIS on or off, hand held or tripod mounted. This is the lens which alerted me to the issue of shutter shock blur. I do not know whether Panasonic has rectified the blur problems with this lens.

So we come to the 45-150mm. If this lens had appeared a few years ago it might have been hailed as a near miraculous optical, electronic and mechanical achievement. But us consumers get a bit blasé about the march of technology and tend to regard it now as  just another budget zoom.  I have discovered it to be a very good lens and the fact it is available over the counter retail in a street front camera shop in the Sydney CBD for only $300 seems quite remarkable to me.  It comes supplied with a lens hood, which can be reverse bayonet mounted.

Description  The 45-150mm is a very compact, light, general purpose midrange zoom which is often bundled in a twin lens kit with the G5 camera.  It is smaller than the other two Panasonic mid range zooms, but with less zoom range,  and even smaller than the Olympus 40-150mm zoom. It weighs 195 grams bare and 225 grams with front and rear lens caps and 52mm UV filter. Build quality appears to be excellent. The zoom ring operates very smoothly as does the focus ring.  The lens mount is metal.  The front section which takes a 52mm filter, does not rotate with zoom or focus. Like most, posibly all M43 zooms this one is a varifocal which means it must be refocussed after zooming. There are no distance  markings or interface modules on the lens barrel. I find the absence of OIS ON/OFF  and AF/MF switches disappointing as I prefer to have these  functions on set and seemodules on the lens barrel where I can see and adjust  them easily without having to enter the Q menu. I guess their absence helps keep the cost down.  My copy is clean with no dust or other foreign body having yet appeared inside the glass. As with other Panasonic lenses with OIS the 45-150 rattles when shaken from side to side when unpowered.

Focus   On the G5 body AF single is fast and accurate in a wide variety of conditions. In several hundred test photos which I made for this review, almost all  the AF single shots were in focus on the active AF area.  My notes do record a slight tendency to misfocussing at 150mm with distant subjects, but even there the great majority of frames were in sharp focus.  I also ran several tests with the G5 set to AF Continuous and M Burst Mode [4fps] on moving subjects with the lens at 150mm. About 70% of frames of moving vehicles and board surfers were in sharp focus, given a fairly steady rate of subject progress and good light. In lower light levels follow focus on a moving subject was less reliable.  Manual focus with MF assist is easy to achieve. 

Optical Image Stabiliser (OIS)   I ran several tests of OIS effectiveness, with mixed results. The most unambiguous benefit of OIS is to steady the EVF preview at the long end of the lens. Otherwise I got results which differed from one test run to the next. In fact I found that the effects of camera shake, shutter shock, OIS and eShutter  were very difficult to untangle in my test schedules. On some test runs at 150mm I got sharp frames with OIS on at 1/10 and 1/13, blurring at 1/15-1-30 then sharp again from 1/60 up. The runs of the same subject with OIS off produced very blurred frames at 1/10-1/13 as expected but inconsistent results in the range 1/40-1/200. Overall with OIS switched on, there was a modest but inconsistent tendency to sharper frames in the shutter speed range 1-2 stops slower than the inverse of [focal length]x2.

Shutter Shock and eShutter  I obtained variable results for image sharpness in the shutter speed range [1/20-1/200sec] previously identified as potentially being affected by shutter shock. When hand held I found occasional but inconsistent advantage to using eShutter in the range 1/20-1/200. On a tripod the picture was clearer with definite advantage to use of the eShutter from 1/30-1/200sec. Does handholding act as a damper for shutter shock ? Perhaps, I'm not sure but it seems possible.

Sharpness/resolution  I checked this at two distances as I have found a lens will often perform better with close than far subjects or vice versa. I used a simple test chart at  40x focal length and a stand of casuarina trees with uniformly fine foliage at  1000x focal length. I tested the Panasonic 45-150mm alongside the Panasonic 14-45mm, Panasonic 100-300mm and Olympus 40-150mm at comparable focal lengths. I was also testing the Panasonic 12-35mm f2.8 at the same time so I had that as a benchmark.

To cut a long story short, the Panasonic 45-150mm and Olympus 40-150mm gave virtually identical results across the focal length and aperture range.  Both performed well on the test chart and trees. The Panasonic 100-300mm was just detectably  better at 100 and 150mm in the casuarina trees but not on the test chart. Results for the 45-150mm were very good across the focal length and aperture range with no weak  areas detected on my copy and no decentering. Corners were a little softer than the center but tidied up well with 1/3 or 2/3 stop smaller aperture in most cases. The exception was at 150mm which seemed best wide open at f5.6 on most of my test runs. In fact f5.6 appeared to be the best aperture for the 45-150mm at all focal lengths.   Fine detail resolution across the frame with the 45-150mm was less than the 14-45mm which in turn was slightly less than the 12-35mm. Rendition of fine surface textures is good but not up to the standard of the 14-45mm and noticeably  less crisp than the 12-35mm.

Chromatic aberration and purple fringing  CA from Pansonic lenses is corrected in Panasonic cameras so CA is not an issue on the G5. Neither did I find evidence of purple fringing. The story might be different on an Olympus camera. Panasonic lenses often prove to have significant CA which is not corrected by Olympus bodies.

Corner Shading  is quite apparent at the widest aperture, becoming less apparent as the aperture is reduced 1-1.5 stops.

Drawing  There is mild barrel distortion at the wide end and mild pincushion at the long end.

Bokeh  Rendition of out of focus subject elements in front of and behind the subject in focus is smooth and unobtrusive.

Contrast/microcontrast This is clearly less than is delivered by the 12-35mm and 14-45mm lenses but responds well to a little Contrast/Clarity tweaking  in Adobe Camera Raw.

Flares  The lens handles sun in frame well with mild veiling flare. With the sun at frame edge or just out of frame it is easy enough to provoke veiling flare and  green spots with or without magenta flares. None of this is a problem unless one is deliberately trying to provoke flares, however regular use of the lens hood would be prudent.

Close up  The closest focus distance is 790mm measured to the sensor plane. Image quality is good across the frame at this distance. The Olympus 40-150mm will focus to 670mm but at this distance the frame edges are very blurred so the lens is not really useful. The Panasonic 45-150mm will accept screw on close up filters. I tried a Nikon 3T with the lens at 75mm giving decent quality photos of small subjects such as flowers.

On tripod  This lens is a good match for the Panasonic G5 camera which offers eShutter which is definitely useful with the camera on tripod.  Switch OIS off and eShutter on, use remote shutter release or timer delay. eShutter is not available for shutter speeds longer than 1 second.

Hand Held   Switch OIS on. Where possible use a shutter speed equal to or faster than the reciprocal of [focal length]x2.  This is 1/100sec at the wide end and 1/320sec at the long end. Experiment with eShutter if your camera has it, using your own technique. Do not expect OIS to compensate for unsteady camera holding.

Conclusion  When the Micro Four Thirds System was introduced about four years ago it promised to deliver imaging performance similar to that of  traditional 35mm cameras but in a much more compact package. With lenses like the 45-150mm, M43 delivers on that promise. This lens is small, light and  inexpensive yet is able to deliver very good results with a variety of subjects and conditions. It would make a good companion to the excellent Panasonic 14-45mm standard zoom on a Panasonic body with eShutter.  [only available on the G5 and GH3 as I write] For an Olympus body the Olympus 40-150mm lens might be more suitable.