Learning to Defocus
In two weeks, these lovely people are getting married:
And your intrepid blogger will be there, snapping away.
Not one to let an opportunity go to waste, I have used this upcoming event as an excuse to buy a new lens. This news would normally be a bit dull — I buy new pieces of kit on occasion, after all — this is the first time I have bought any piece of photography gear with a goal in mind. My particular concern is that I cannot spend the wedding in people’s faces, and expect much of the evening to be in a relatively dark room.
I need a long, fast lens.
Longer lenses tend to be more expensive than their wider-angle counterparts.
And faster lenses are always more expensive than those with a smaller maximum aperture.
Treading into expensive territory, there are further thoughts:
Wedding photography is, to a large extent, portrait photography. My photography is, for the most part, portrait photography. And there is a lens that is reputed to be the best portrait lens in the world.
Why not buy that one?
Why not, indeed.
So … a lens review
Reviewing this lens is easy:
It is awesome. It is, by far, the best lens I have ever attached to my camera. It is far-and-away the best built lens I own. I can simply feel it by picking it up. It’s amazing.
Beyond that, it packs all the awesomeness implied by 135mm f/2. It’s hella sharp. It handles like a wet dream.
But the thing that makes this lens special is the defocus control. The “defocus” bit is a translation of “bokeh” from the Japanese. Bokeh, of course, should not be translated; it’s still bokeh. But I digress.
Control over the out-of-focus bits is what reputedly sets this lens apart from the other contenders for the “best portrait lens in the world” award.
Defocusing. Bokehing. And whatnot.
So … defocus control. I has it. But what on earth does it do, other than controlling the blurring?
I found three willing models, and put them at three different distances from the camera. A tripod was procured. Set the aperture at 4.0, shutter speed to 1.3 seconds. Autofocus pointed at the duck.
Defocus control at 0:
Nice duck.
I then started to rotate the defocus control towards the “F” (front).
First, 2.0 (half the aperture):
I can’t tell the difference; increasing it to 4.0 – the same value as the aperture:
The duck is still sharp as a tack here. Can’t see any difference with the owl in the rear. The koala in the foreground seems slightly … smoother? I’m not sure if that’s the right word, but I can see how this could dull a slightly sharp-ish bokeh. The koala, it should be noted, does not provide particularly sharp bokeh.
Next, I turn it all the way to 11. Or all the way to the “F”, anyway:
The koala is even smoother, but what jumps at me now is the owl’s eyes and the bubble wrap in the background. It seems that whatever smoothing is happening in the foreground, the opposite happens in the background.
Now we move in the other direction – defocus control towards the rear, at 2.0:
4.0:
And all the way to R:
It seems more evident modifying the background than it did the foreground — whether this is a trick of the mind, a trick of the lens, or a product of the relative distances involved, I’m not sure. It could also be that the owl has those distinctive round eyes as references.
But the owl clearly gets increasingly blurry with additional defocus control. The koala also gets notably sharper.
We’re sticking things out of focus, though, so really we should minimize the depth of field.
Cranking the aperture to 2.0 (and adjusting the shutter speed accordingly), we take a fresh photo with the Defocus Control at 0:
Wide open, we can see how awesome this lens is. It’s sweet.
Our next stop is to defocus towards the front — going straight to the aperture value of 2.0:
Again, I find moving towards the front to be incredibly subtle.
Pushing past the aperture, to 4.0 and all the way to “F”:
The larger aperture really shows what’s going on — the owl becomes sharper in the background, the koala “smoother” (I’m still searching for that better word) in the foreground, and the focal point – the duck – gets softer.
The interesting effect here, for me, comes at about double the aperture — the circles from the owl’s eyes and the bubble wrap in the background seem to leap out; the koala is significantly more blurred, and the duck has that touch of softness to the focus which can make certain pictures lovely. These things all become overstated, and less pleasant (except perhaps our blurry koala) when pushed to the extreme in the final photo.
Now, to the rear.
2.0:
4.0:
“R”:
Again, I can note the difference here more readily when moving towards the rear than the front, with the owl looking significantly more blurred without any visible impact to the duck or koala at this resolution.
Pushing to double the aperture again creates that soft focus effect on the duck, but the sharpening of the koala in the foreground looks far more awkward than it did when the owl was sharpened in the background; still, this could be a fantastic choice without the foreground object.
The final photo looks like a bad photo of the koala, rather than a defocused photo of the duck. Again, this is an overwhelming version of an otherwise interesting effect.
Final words
Defocus control appears to be pretty awesome. This lens gets some decent bokeh with the defocus set to zero:
That this bokeh can be sharpened or smoothed easily? Simply awesome.
It’s going to take some time before I have a strong feel for it — probably longer than the three weeks until the wedding; I won’t be a master by then.
But the toy I bought myself for the wedding?
It’s going to be fun to play with for a while longer than that.
