Prime Numbers / by Graham Dew

In my camera bag, 20 and 45 are prime numbers. Or to be more precise, I have two fixed focal length prime lenses of 20mm and 45mm. These are my prime lenses in terms of use and choice too; I use these two lenses in preference to the standard zoom that came with the camera. I also know that any new lens I might buy in the future will not get the same level of use as these two lenses, which helps me resist doing further damage to the bank account.

New hedge near Corhampton, #1 © Graham Dew 2012
New hedge near Corhampton, #1

The two lenses I’m talking about are the Panasonic Lumix 20mm/f1.7 standard lens and the Olympus 45mm/f1.8 short telephoto. When I bought my Lumix G3, one of the big attractions of the m43 system was the availability of these highly praised lenses. You can find plenty of reviews on the web about how excellent these lenses are and they are all true. Both are very sharp, very bright and very light, and fortunately, reasonably priced. And they both share the same trump card; they are both excellent when used at full aperture.  It is this quality, which allows one to create sharply drawn detail against a softly rendered background that makes these lenses so appealing.

New hedge near Corhampton, #2 © Graham Dew 2012
New hedge near Corhampton, #2 © Graham Dew 2012
The 20 was the first lens that I got. A pancake lens, much wider than it is long, it gives the camera a very low profile which just about allows one the opportunity to put the camera into a pouch. It weighs next to nothing, and allows you to tuck the camera under your arm discretely. Optically it is very clear and sharp, no visible distortion. The great appeal of this lens is that it can truly be used wide open, with pleasing depth of field drop depending on the closeness of the subject. If you need more depth of field, commonly when focussing on nearby object, you can always dial in more depth by setting the aperture smaller. Optically, the lens is very good indeed. The tonality, sharpness, and transition from sharp to blurred is as good as you could wish for. The only thing I would really like to improve is the focussing. Many of my pictures are of objects close-up. If the object is small or thin, then the AF has trouble focussing. The lens will hunt from near to far, often passing through the chosen point of focus. As the focus is quite slow (slower than the kit zoom) this can take some time. When this happens I switch to using the pin-point mode of the G3, which usually helps to find the focus. Overall, it’s a great lens and one I grow to enjoy more and more. It is now my normal lens, the one lens I'll take if I'm limiting myself to the minimum gear.

New hedge near Corhampton, #3© Graham Dew 2012
New hedge near Corhampton, #3
The 45mm is the same but different. Again, it has very high image quality, can be used wide open too and is also very small and light. But the depth of field effects are even stronger as one would expect from a longer focal length. This Olympus lens is much faster at focussing than the Panasonic lens and always seems to lock onto the desired object quickly snapping into focus. Its shape is different too. The barrel of the lens is smaller than any other lens I have owned, even smaller than the lens mount. It just feels tiny in the hand and on the camera. Like the Lumix the barrel construction is plastic, but silver finished as opposed to the gunmetal colour of the Lumix.

New hedge near Corhampton, #4 © Graham Dew 2012
New hedge near Corhampton, #4
The only control on either of the lenses is the manual focus ring; something I rarely use. For hand held close up work you really want to take the picture as soon as the focus is achieved, and this is best done with AF. Neither of the lenses have image stabilisation. When used at large apertures the shutter speed stays high in a wide range of uses so this is not often an issue, especially coupled with the clean images I get from the G3 at high ISOs.

New hedge near Corhampton, #5 © Graham Dew 2012
New hedge near Corhampton, #5
As I mentioned in the first ever post on Joined Up Pictures, I’m really interested in depiction and the way we perceive things, how we turn three-dimensional space into a flat 2D image. When there is a lot to be seen, joiners have a special appeal, allowing an image to be built from multiple viewpoints and memories. But there are times when one looks with a focused gaze on a single object, usually something in the near-field, and these lenses do a good job in replicating that experience. When making near-field pictures control of the background is every bit as important as the main subject. Position, lighting and colour are all important aspects of making such an image, but the ability to soften the background through out-of-focus blur is probably one of the most effective ways to de-emphasise the surroundings.

Joiners might be considered to be a quite radical manipulation of images, but other than making joiners and performing tonal adjustments, I really don’t like modifying images in software. I prefer to make the image in-camera, using the lens and shutter for control of blur. The camera lens behaves like our eye, so focus and blurring only have believable three-dimensionality when done in camera. In fact, the Lumix 20mm has a focal length and field of view that almost exactly matches the human eye, perhaps making it the most natural of any lens available today.

New hedge near Corhampton, #6 © Graham Dew 2012
New hedge near Corhampton, #6
I’m really pleased with both of these lenses and recommend them to anyone using m43 camera. The 20 is a very nice lens for photographing things, the 45 for people. The other day I came across a brochure from the late 80s for the Leica M6, a camera that I would have loved to own at the time. At the back of the brochure it suggested a few kits of bodies and lenses for a number of purposes. The small kit recommended for travel and street shooting was an M6 body with a 35mm & a 90mm lens. A quarter of a century later I still can’t afford a Leica, but have arrived at their recommendation of focal lengths.