Bokeh on the CV 40/1.4

[sockeyed]

My new CV 40/1.4 is a gorgeous lens, in that it is super-fast, very sharp, and has great colour rendition. It is the single-coated version, so the contrast is very attractive (I haven't tried it in B&W yet, where it should excel). The bokeh, however, scares me a little. Check it out in this sample (shot with my R3A on NPH). Of course, the background is a bit extreme, with lots of angles and colours, but I do find the results distracting.

Thoughts?

 

[Fedzilla_Bob]

It looks like when I don't have my glasses on, a slight double vision blur.

Which seems odd to me. I would expect that from an aperture iris like that used in a Minox 35 where you have two leaves that form the aperture in a diamond like shape.

Is there the possiblity of a slight camera shake?

 

[sockeyed]

I'll try and post more samples, but I see it in every image shot fully open or close to it, so I don't think it's camera shake.

 

[felipe]

There was a thread some 2 months (?) ago on this very topic.
It seems that in some situations the noktons bokeh is out of control, while in others it's pretty smooth and/or subtle.

Appartenly the rendering of out of focus areas depends on distance (to the subject, from the subject to the blurred background, etc.) and on whether the oof area is in the foreground or the background area of the image.

The harsh and ugly bokeh of the 40 is really a dissapointment, I'd buy it instantly if they "fixed" this.

Seems to be a great lens otherwise.

phil

edit:
I remember Lars (where's he anyway??) had some pics posted made with the 40MC wide open with equally horrifying bokeh - he eventually sold it I think.

 

[furcafe]

My understanding is that the shape of the aperture has only a partial effect on boke/out-of-focus areas. I don't find the boke in the shot to be particularly objectionable, but then I can easily tolerate even Noctilux blur. 😉 I agree that the background is a little "extreme" as backgrounds go.

Personally, I've have no complaints about my 40/1.4 Nokton (regular multicoated version).

It looks like when I don't have my glasses on, a slight double vision blur.

Which seems odd to me. I would expect that from an aperture iris like that used in a Minox 35 where you have two leaves that form the aperture in a diamond like shape.

Is there the possiblity of a slight camera shake?

 

[aizan]

You could see in Sean's fast lens test that all of them had a sweet spot two stops down around f2.8. Try using f2.8 for busy backgrounds, and reserve 1.4 for simple backgrounds and "no out-of-focus background" type pics.

 

[sockeyed]

Great tip. Thanks Aizan. I'll try and shoot some samples at different apertures and post them here.

 

[sychan]

Well, that shot is a "bokeh hazard" - the background is full of large, high contrast, heavily saturated objects and the subject is low contrast and lightly colored. The nokton's bokeh isn't as smooth as one could hope for, but as others have pointed out, the effects seem to diminish when you stop it down (and, as I've mentioned elsewhere, the Cron-C exhibits the same bokeh characteristics).

Check out the flare suppression from the 40MC on this totally backlit shot.

 

[timeUnit]

I agree to some extent. The Nokton is slightly short to be a bokeh-machine, or at least that's my conclusion. Comparing with the Zuiko 50/1.4 on my Olympus OM-1n, there is a big difference in bokeh that I belive to be of these factors:
1) Shorter near focusing limit, ca .45 meters (1.5 feet)
2) Longer focal length with same aperture.
3) Different construction: larger diameter, larger lenses etc.

I was a bit disappointed about the bokeh on the Nokton, I thought it would be much more of it at f/1.4 and f/2. On the other hand, bokeh is really not what it's supposed to do: it's a fast 40 mm, perfect for indoor reportage, portraits of people in action etc. A little wider than 50 mm, to fit in tight situations, but still very fast and not as large and heavy as a 35/1.4 or 1.2.

Look here for a recent and decent shot with the Nokton:
http://blog.hform.se/article/91/think-box-1

There are some more shots on the blog with the same lens like this one:
http://blog.hform.se/article/85/mono-in-mono

Look here for an example (albeit not the best) of the bokeh of the Zuiko 50/1.4 at a distance of about 2.5 meters and around f/2:
http://blog.hform.se/article/81/kaf233-marmelad
Quite a difference, methinks.

The Nokton is not a super creamy bokeh machine, but very useful and nice lens in all those situations were you actually want the backgound to be a part of the pic. 🙂

*h

 

[Huck Finn]

I agree with Sychan. I'm not sure what any lens could have done with all of the high contrast clutter in the background of that shot - especially given that you were using color film. The only way to test this would be to shoot the exact same scene with a 35 Summilux & see what it does with it. I think that it's a very pleasing shot of the child.

Huck

 

[sockeyed]

Thanks for all of your comments - this is an interesting discussion.

Having shot with f/2 and 2.5 lenses for much of this year, it's quite amazing to have a lens that shoots at 1.4, especially since it's so small. I seldom shoot wide open, but now I have the option when the picture needs to be taken.

I've already come to like the 40mm focal length - the images just seem so natural.

I've taken a few test shots at 1.4, 2.8 and 5.6. When I get them processed, I'll be sure to share them.

 

[DaveSee]

I have been shooting this lens only a short while, and not scientifically: that is, I have not done
a side-by-side comparison with my Summicron 35, nor my 50 Summilux. I have yet to see the
"edgy bokeh"( would that be "airport terminal SOFA"? ) in pics thus far...

...OK, OK, I'll finish the BW400CN roll today!

Anyhoo, attached is a shot from about 1 meter, at f/2.8... note that it *is* sunlight too.
I scanned this neg rather hastily: first RAW, then re-scanned the RAW to JPEG.

Colors and perspective are very pleasing with this lens, IMHO.

rgds,
Dave

 

[vsolanoy]

I've already come to like the 40mm focal length - the images just seem so natural.

I've noticed the same -- I'm enjoying the 40mm focal length enormously.

 

[sockeyed]

I did some test shots on the weekend, shooting the same subject with a complex background at 1.4, 2.8 and 5.6. By 2.8, the bokeh smoothed out noticably.

My first prints - NPH printed on a Fuji Frontier - are gorgeous! They are incredibly sharp with lovely 3D rendering and accurate colours. This has to be the best lens I've used.

 

[jdos2]

Contrast it to a Voigtlander Nokton 50mm. From 1952.

 

[Doug]

Noktons of differing vintages and designs... 🙂

JD, according to what I've read, that shot shows evidence of overcorrected spherical abberation, like my Jupiter-8 but more strongly.

 

[jdos2]

The "football" shaped highlights are physical vignetting- it's teeny and its exit aperture is a bit too small. Otherwise, it's sharp, even wide open, with only a bit of veil. It's a lens I'd love to have in Leica mount!

 

[Doug]

The "football" shaped highlights are physical vignetting- it's teeny and its exit aperture is a bit too small.

I thought these explanations were useful:
http://www.luminous-landscape.com/essays/bokeh.shtml
http://www.kenrockwell.com/tech/bokeh.htm

 

[jdos2]

Agreed! (1 space for the filter)

 

[sockeyed]

Bokeh revisted

Bokeh revisted

Here are two more shots, taken last weekend on APX 100. I think that they show how the bokeh, while never 'creamy', does improve substantially when stopped down. I believe that these where taken at around 5.6 and 2.8 respectively.

The ice cream, however, is quite creamy.