On 12/17/2016 10:17 PM, Moose wrote:
On 12/17/2016 3:17 PM, Mike Gordon via olympus wrote:
That is a very very interesting lens and I hope you post some images with it.
. . .
I even have the 85/2 out, mounted for the A7, to shoot with the Nikon Soft filters, to compare to the Varisoft at the
same FL and apertures. But that's at least 20 exposures with the Varisoft for combinations of aperture and Soft
setting, and 18 with the 85/2. And my interest in shooting tests has waned for now. It'll be back, I imagine.
As I had hoped, writing that spurred me on, and I did more test shots.
The tests of Nikkor Soft filters are easiest to describe. In the Nikon article about soft focus, it says "There was
little reduction in the effects of flare, and they remained relatively great, even with smaller apertures."
<http://www.nikkor.com/story/0051/>
That's something of an understatement. From f2 to f2.8, there is a slight change, mostly brightness. From f2.8 to f16,
the images are all identical, as far as I can see. This makes me happy that I started with flat test targets. I suspect
that with complex, 3D subjects, it would be easy to confuse DoF effects with softening effects. Knowing that the
softening effect is the same across apertures allows choice of DoF separate from softening.
The Nikkor article is interesting, as it also chronicles the earlier effort to design a soft focus Nikkor lens, which
ended in failure to minimize the loss of softening as aperture gets smaller, while retaining the other desired
characteristics. It's not explicit in the article, but seems to say that the move to special filter technology was an
approach to the same problem that they couldn't solve with a lens.
The Varisoft is Minolta's effort at a soft focus lens, coming out a few years after the Nikkor Soft Filters. It's as
though they were struggling with the problem so succinctly stated in the Nikkor article: "With soft focus lenses, the
aperture setting has less to do with exposure than it does with adjusting the degree of softening performed."
I've found that to be true, and a significant limitation, with my other soft focus lenses, both the intentionally so,
like the LensBaby Velvet 56 and unintentionally, as with the 28, 35 & 138 f2.8 T-Mount lenses. You get either soft - or
deep - but not both.
Minolta is different, with variable softness. There's a ring marked from 0 to 3, with detents at 1 & 2, but also
continuously variable. Perhaps the idea was that when stopping down, the Soft ring can be turned up, to get a similar
effect? It doesn't work that way.
At f4, Soft 0.5 gives an overall soft look, while maintaining the same amount of visible detail as at zero. F8, Soft 2,
gives about the same resolution, but a MUCH different look, with slightly funny edges kinda like a USM effect. It has a
broader useful aperture range than the others above, but isn't very useful past f5.6.
BUT, it has another oddity. As the Soft ring is adjusted, image size changes. I didn't expect this, but a little thought
made the likely reason clear. This is an MF lens, designed for film, so focus needs to stay the same as it is adjusted.
There was no live view magnified focus and no chimping focus after the shot.
Obviously, the Soft adjustment changes FL, shortening as it increases softness. To maintain focus, a part of the barrel
moves back as the Soft setting increases. This is a different part than moves with the focus ring, and carries the focus
mechanism with it. The shorter FL results in a smaller image.
This is all very clever, but makes one of my processing strategies impractical with this lens. I have planned to take
tripod shots at different softnesses, then apply softness differentially, using masks in PS. There's not only painting
the effect in and out and gradients; it's also possible to fine tune it around high contrast edges, or the reverse. In
addition to the PS Find Edges function, I have other plug-ins which are more flexible.
I can't do that sort of stuff with different sized images, at least without
resampling, which comes with its own gremlins.
Head Spinning Moose
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What if the Hokey Pokey *IS* what it's all about?
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