Ultra fast 50.

Thank you, Andrew.

As other's have suggested, the value of the 50/1.2 is the dreamy wide open performance. By f2/2.8 the lens is really starting to shine as far as sharpness is concerned and bokeh is still quite creamy. It then goes through an area of apertures that the bokeh can be a little bit harsh over about f5.6 or so and then gets better again after f8, but this all depends on camera to subejt disatance and subject to background distance. I think the 50/1.2 is meant to be used at the wide open apertures up to f4 more than apertures over f5.6 and thus would be excellent for portraiture.

f2.5. Superb, IMO. Sharp and nice bokeh.




f8. A little harsh. Sharp, but bokeh suffers.




f4. Not too bad. Sharp and bokeh quite ok.

OK it official I'm a Luddite.

you all see art

I see blurred image.

If I wanted to paint I'd buy an easel.

I suspect getting that blurred/dreamy effect would be pretty easy with any half decent zoom and decent photo-editing software.

Lets see anyone turn those f1.2 shots into sharp, textured accurate images of the subject.

Nice second series though Lance looks the the 1.2 can really shine at f2.8 and above.

I like my bokeh a 'little harsh' hence why I've always preferred the f1.7's over the imo soft 1.4's

Is this really practical though? For portraits with a 50mm lens, you're going to be quite close. And at apertures large enough to get the dreamy softness, you're going to have a wafer thin depth of field.


I don't think this makes you a Luddite, it's just a preference. Perfectly reasonable IMO.

I'm somewhere in the middle - I can't paint, and I like the dreamy effect in certain circumstances. But not enough to justify buying an A1.2, except as an investment perhaps, and once owned as such, an occasional curiosity.

Thank you for your kind appraisal, Andrew.

The problem here is also of a little bit of reduction issue with Pentax User reducing the images from their original 1000 pixel width to the small 800pixel width and thus taking the edge off their sharpness as they do look sharper on my PBase site.

Having said that, the dreamy look to the bokeh at the very wide apertures can be used in some instances for a particular effect that may be required. On the shot of the fragapani at f1.2, the DOF is only about 5mm, so there is very little of that shot that actually is in focus!

Here is a shot from the A50/1.2 @ f5:




And one at f6.3




A crop:




Again, the two landscape shots are at 1024 pixel width so suffer somewhat from the reduction of Pentax User forum. The vertical image is ok as it is a 800pixel high shot.

I still need to find a program that can decently simulate lens bokeh, they simply can and will probably never will since they can't see depth and therefore can not create a good true to life bokeh.

Here comes the counter question, why does it need to be sharp?
I'm sure a woman would appreciate a soft lens

Pleasant though bokeh often is in a photographic image, one thing it definitely isn't, is true to life.

When you look at something with your eyes, you see it as sharp as your eyes can focus, and when you're looking at something, it's very hard to be aware of the out of focus areas of the field in any kind of detail.

So whatever 'true to life' bokeh is, I'd be surprised if anyone can be aware enough of it in detail sufficient to compare with photographic bokeh.

_
(Edit: or did you mean 'true to life' as 'produced by a real lens'? Sorry if I've misunderstood.)

Undoubtedly, and not just women! But as I said before, the wafer thin DOF at the very wide apertures will have other effects. Is the softness in a portrait from the F1.2 going to differ that much from just defocusing a sharper lens a little?

Chris with "true to life" I mean Like a lens would do in real life.

What a program basicly do is shake the pixels together and make an average, it isn't that simple but that is basicly it.
So if something is close it will just have as much blur then something that would be far away.
It of course depend on the image and the effort that someone put in it.

That depends on the type of photo again since you need to place the DOF so that it wouldn't capture anything so to say.
If the DOF goes out of focus infront and rear of the subject then you've a problem.
The second photo Lance posted on page 2 is such an example.

Just show me what you can do with a program, it will take a lot of time to get it like a lens would do

I'm not at all disagreeing with you - I'm just questioning how easy to use it would be as a portrait lens when wide open, or nearly so. If the subject's face was square to the camera, you'd be able to get both eyes in focus, for instance, but at an angle you quite likely wouldn't.

That first photo in the series at F1.2 is a good example of what I mean - the flower square on to the camera is Ok - pleasantly soft, but the one at an angle isn't really in focus at all other than the closest part of it. In a portrait this would present difficulties.

Chris you're right about that.

It's not doable to make a portrait wide open with that lens.

In a way you might be better of with for example the DA*50-135 for portrait, a lot better even since you don't need to switch lens for the different shots.

I was not advocating using the lens wide open, but stopped down a few stops, as is best to do with any lens, to begin to get the best out of it.

As with any lens, it's important to know what it has been designed for.

The f1.2 has a very wide aperture to enable manual focusing in very low light. It also has superb control of coma distortion, so point light sources are well under control, more so than any other 50mm Pentax lens.

f1.2 DOF is very, very shallow, so close ups at open aperture are not really the intended use. The curvature of field would also preclude this, although in some circumstances this could be used to advantage.

Stopped down to a normal working aperture of f8 and beyond it behaves as well as any other 50mm for general subjects. Focusing will still be very, very precise though, or very, very tricky if you have problems with MF.

I think you've summed it up admirably, John.

Without my glasses on, I get great bokeh

Without mine I can't read the forum