There once was a time when SLR cameras came kitted with a truly decent lens, not some rubbish 18-55 fslow-fpitchblack. This was a time when cameras were still made of metal and people shot organic film. The lens was the 50mm f1.8 and is one of the cheapest and most useful second hand manual focus lenses that you can find, for nearly any lens mount.
Canon make a modern AF 50mm f1.8 that is dirt cheap and handy, but it doesn't come as a kit with any of their cameras which I think is a shame. I think it has something to do with the fact that 50mm in 35mm terms is just so easy to make. In the 'normal' range of lenses ie; 40mm-85mm, f1.8 is a pretty standard lens speed. It is kind of fast but not fast enough to command a huge price or need a ridiculously sized filter. But with different sized sensors now available, these normal focal lengths take on a different character and are harder to make.
In the m4/3 line up, to get a 40-85mm lens, a manufacturer has to make a lens that is between 20mm and 45mm. We have these lenses but because they are quite unique in that they would be inherently wide on other systems, their prices are a little dear. The closest lens to the über cheap and ubiquitous 50mm f1.8 is the Olympus 45mm f1.8, which I consider to be a typification of modern photography in general. Read on and I may stop rambling.
Size wise, the 45mm is very small and light, the adapter on the 50mm nearly doubles the size of the lens.
On a m4/3 camera like the Olympus OM-D EM-5, a 50mm becomes a 100mm lens due to the 2x crop factor of the smaller sensor. This is fine. With a 50mm f1.8 OM Zuiko, we now have an image stabilised 100mm f1.8 lens. But how does this older lens compare against it's younger relative?
From using a few older manual focus lenses adapted to digital cameras, I have noticed that these older film lenses just can't hack focus on targets further away and that contrast is lost. Like in the scene below, I focussed on the ugly apartment building and the differences are immense right off the bat.
(the OM 50mm is on the left, the 45mm on the right)
ƒ1.8
ƒ2.8
ƒ5.6
ƒ11
So I focussed on the ugly apartment building but the clock tower is out of focus in the 50mm f1.8 images even though they are a similar distance away... weird... But notice how the 45mm is perfectly sharp and in focus? Even at 100% there is no fault nor flaw in the 45mm images. The 50mm on the other hand... softer at every stop but at ƒ5.6 it is sharp enough.
Now for medium distances:
ƒ1.8
ƒ2.8
ƒ5.6
ƒ11
Again, the 50mm is softer than the 45mm but notice how the colours are different? These are all RAW images that I then matched the white balance and tint but still the older lens has a softer and less digital look.
Now for subject isolation with a working distance of 1.5m to the bottles, focussed on the sauce label:
ƒ1.8
ƒ2.8
ƒ5.6
ƒ11
Here, as before, the 45mm is sharper, more clinical BUT, the out of focus areas are also smoother and there is more saturation and punch. The 50mm is softer, more muted in it's colours and the camera also slightly over exposed the images as opposed to the 45mm. The bokeh characters are different between the 2 lenses, the 45mm is smoother which I quite like but take the 50mm to an area with leafs or grass as a background and you get an awesome vintage swirl of bokeh.
And now even closer. These were taken at the 2 lenses closest focusing distances which turned out to be roughly the same! So about 500mm to the target. I focussed on the aperture indicator on the front of the lens barrel. Didn't have anything too interesting lying around so some gratuitous camera porn will have to do.
ƒ1.8
ƒ2.8
ƒ5.6
ƒ11
So depth of field is similar between the lenses but again, the 45mm is sharper but has a different colour and tone to the images. I prefer the muted tones of the 50mm to be honest and this is one of the reasons why I love using this old lens on my OM-D.
Olympus 45mm f1.8
+Auto focus, super quick and accurate for capturing the moment.
+Sharp across the frame from f1.8
+Small
+Light
+1/3 aperture stops for accurate exposure
-Moderately priced but not too expensive
-Looks silly when on the camera, I get space saving but why does it have to taper?
-Manual focus ring lags a little and is annoying for minute focus changes
-Mini filters are a worry, I haven't lost any yet but...
-Plastic plastic plastic
-Silly plastic lens hood
Olympus 50mm f1.8
+Manual focus, makes me slow down and think about the shot
+Smooth manual focus ring
+External aperture ring
+Good size to hold and play with
+Natural colour rendition
+Metal body
-Not very usable at f1.8, better on film than digital.
-Softer images
-Hard to get good images at longer distance from the lens
-No EXIF data on files, mildly annoying but not critical.
So why do I have both lenses? Well both have their uses. The 45mm delivers consistently great images and I can rely on it to lock focus and bring out punchy, digital colours. But that is why I have the 50mm too. I rarely use it at f1.8 unless it is dark so it is relegated to a 50mm f2.8 which is fine. I still get good subject isolation and the images are still sharp enough but have a nice and natural softness and colour to them which I think is very important. I think that this is where the grandfather and the young relative analogy comes into play:
Digital is so predictable, there is no such thing as a bad camera any more and most digital images look clinical, too precise. That is fine, it is a look that I try push for in my digital images to distinguish from my film photography. But there are times where I get sick of my camera and lens nailing every shot. Sure I put work into carefully manually exposing and framing a shot but the camera and lens is getting everything too in focus some times, too sharp, too digital. And that is why I love using the old OM Zuiko 50mm f1.8 as well as the new 45mm f1.8.
tl;dr
You cannot fault the 45mm and that is one of it's problems, it doesn't have a lot of character or soul.
ps; on a side note, I was looking through some of my old Canon 1ds files and I miss the almost film like quality of those old big pixels. Why can't they make some new cameras with less megapixels? Like a revived 11mp full frame or a 6mp m4/3 sensor? Fat pixels are bad ass.
