Jump to content

Noctilux 0.95 purple fringe


Recommended Posts

Advertisement (gone after registration)

In the German forum a member from Switzerland points out that the Noctilux 0.95 produces purple/violet fringes at full opening in daylight on the fringes of strong black/white subjects, i.e. very strong contrasts. I have noticed the same thing using it with the M9 for a few days and felt relieved that someone else had noticed it in confirmation of my results.

On contacting Leica in Switzerland the answer to the Swiss forum member was that the phenomenon is caused, I quote "physikalisch vorgegeben" which I interpret as meaning caused by optical physics and that this "normal" problem can't be corrected by sw (software) or hw (hardware) modifications. The recommendation is to photograph in these conditions at f4.

My problem is that I used the 1.2 and 1.0 Noctiluxes at full opening not only for shots in relatively dark subjects but also for the very small depth of focus. If this is not possible with the 0.95 asph ( I wonder, why I never noticed this normal phenomenen with the old lenses?) the 0.95 loses a great deal of charm for me and I am seriously considering returning the lens and using the old f 1.0 or the 50 1.4 asph which I also own.

Can anyone give me some advice ? Would using a 2 or more times ND filter help? I can't test this, as I do not have any ND filters available now.

Teddy

Link to post
Share on other sites

In the German forum a member from Switzerland points out that the Noctilux 0.95 produces purple/violet fringes at full opening in daylight on the fringes of strong black/white subjects, i.e. very strong contrasts. I have noticed the same thing using it with the M9 for a few days and felt relieved that someone else had noticed it in confirmation of my results.

If we had something to go on, i.e. images demonstrating the issue, it might be possible to provide more than just speculation. It may be purple fringing or it may be chromatic aberration, but based on just a description I wouldn’t go out on a limb and claim it was one or the other.

Edited by mjh
Link to post
Share on other sites

If is only purple/blueish in color it most probably is blooming, i.e. leaking light to neighbouring pixels. This is a purely physical phenomenon, sensor related, and only corrigible in post.

If it is purple/blueish on one side and greenish on the other, like on both side of a twig, it probably is C.A: chromatical abberation and lens related. There may be some left at the edges of the Nocti image circle: Leica speaks of slight deterioration of the image in the corners.

It would take one of those 100K EUR Zeiss lenses for chip-making machines to be entirely rid of lens faults. The Canon 85mm 1.2 L lens has massive amounts of it at full opening, as Chasseur d'Images showed some some time ago.

Link to post
Share on other sites

Advertisement (gone after registration)

In the German forum a member from Switzerland points out that the Noctilux 0.95 produces purple/violet fringes at full opening in daylight on the fringes of strong black/white subjects, i.e. very strong contrasts. I have noticed the same thing using it with the M9 for a few days and felt relieved that someone else had noticed it in confirmation of my results.

On contacting Leica in Switzerland the answer to the Swiss forum member was that the phenomenon is caused, I quote "physikalisch vorgegeben" which I interpret as meaning caused by optical physics and that this "normal" problem can't be corrected by sw (software) or hw (hardware) modifications. The recommendation is to photograph in these conditions at f4.

My problem is that I used the 1.2 and 1.0 Noctiluxes at full opening not only for shots in relatively dark subjects but also for the very small depth of focus. If this is not possible with the 0.95 asph ( I wonder, why I never noticed this normal phenomenen with the old lenses?) the 0.95 loses a great deal of charm for me and I am seriously considering returning the lens and using the old f 1.0 or the 50 1.4 asph which I also own.

Can anyone give me some advice ? Would using a 2 or more times ND filter help? I can't test this, as I do not have any ND filters available now.

Teddy

I had very similar issues with a 35mm summicron, purple fringes in high contrast situations like branches against the sky. To my surprise it only existed in Lightroom, when I developped the images in CaptureOne 5, they where gone. Later I discovered in Lightroom the defringe option in Lightroom which helped to reduce these fringes.

  • Like 1
Link to post
Share on other sites

If we had something to go on, i.e. images demonstrating the issue, it might be possible to provide more than just speculation. It may be purple fringing or it may be chromatic aberration, but based on just a description I wouldn’t go out on a limb and claim it was one or the other.

 

Unfortunately, I deleted the shots with the fringing. I will try and reproduce the phenomenon.

Is there a consensus that the same thing happens with all lenses at large openings?

Teddy

Link to post
Share on other sites

Is there a consensus that the same thing happens with all lenses at large openings?

That would depend on what it is. Chromatic aberration is a product of the lens and is not susceptible to stopping down whereas purple fringing is caused by the sensor (although there is no general consensus on this) and can be reduced by correcting the exposure (though not by stopping down as such).

Link to post
Share on other sites

That would depend on what it is. Chromatic aberration is a product of the lens and is not susceptible to stopping down whereas purple fringing is caused by the sensor (although there is no general consensus on this) and can be reduced by correcting the exposure (though not by stopping down as such).

 

Thanks for the various explanations. I am reasonably sure that it was purple/violet fringing. I will try and reduce the phenomenon by adjusting exposure. I will also try with other lenses at large apertures.

Teddy

Link to post
Share on other sites

This is a sensor issue with the Noct and not a lens issue. I have seen it with Leica, Zeiss and Cv lenses on the M8 and M9 as well as with the Canon 85L on a 5D. If you shoot the Noct on film you should not see this issue at all.

 

Most of my shots with the Noct 1.2 and 1.0 have been on Kodachrome slide film and I have never seen the phenomenon. I have also used the Nikon Noct-Nikkor 58/1.2 with film without noticing.

Only after getting the M9 and very recently the 0.95 asph have I tried in daylight at f0.95 and experienced the reported phenomenon.

Thanks for this information.

Teddy

Link to post
Share on other sites

This was another thread on the subject (there are more)

 

http://www.l-camera-forum.com/leica-forum/digital-post-processing-forum/115965-fringing-technical-problem.html

 

And another thread that elaborates on all the pros and cons of the matter is here:

 

http://www.l-camera-forum.com/leica-forum/leica-m9-forum/107052-m9-50-lux-asph-too-much-2.html

Edited by jaapv
Link to post
Share on other sites

Digital is not perfect, but it is very, very good.

 

There are still things that look better on film, and there are some things film handles better. If you can carry a Digital M and a Film M with you, you can deal with issues that bother you by using the medium you feel works best for a particular situation. This is a personal choice.

Link to post
Share on other sites

This was another thread on the subject (there are more)

 

http://www.l-camera-forum.com/leica-forum/digital-post-processing-forum/115965-fringing-technical-problem.html

 

And another thread that elaborates on all the pros and cons of the matter is here:

 

http://www.l-camera-forum.com/leica-forum/leica-m9-forum/107052-m9-50-lux-asph-too-much-2.html

 

jaapv and others:

Thank you very much for your help. I had previously read the above threads but stupidly did not relate the phenomenon to what I experienced. My mistake.

I repeated the test this morning (M9 0.95, full opening, bare tree branches against bright morning sky and all overexposed shots, irrespective of apertures up to f4 showed the phenomenon. Purple/Violet only, no green so the matter seems settled to me.

I will keep the lens, use it carefully and avoid overexposures. I will also purchase a ND filter in order to use the lens at full opening and get the out of focus effects that I want.

Thanks again,

Teddy

Link to post
Share on other sites

This is a sensor issue with the Noct and not a lens issue. I have seen it with Leica, Zeiss and Cv lenses on the M8 and M9 as well as with the Canon 85L on a 5D. If you shoot the Noct on film you should not see this issue at all.

 

I'm the swiss guy with the noctilux 0.95/50mm asph. I sent five pictures to leica switzerland. They forwared those pictures to solms. And they said it's a physical problem with the lens. No not a problem...it's normal they said. It's not a sensor problem! They told me, that i have to shoot with f4 daytimes :confused: I said that cannot be true. So the chief of leica switzerland made me the offer to return the lens.

i have some photos, but they are really crap.

Link to post
Share on other sites

The purple fringing is due to overfill of the pixels of the sensor with these high speed lenses.

 

There is a simple fix........use capture one pro as your raw converter and click on the purple fringing tab. The problem disappears immediately.

 

Capture One is still the best raw converter out there IMHO. Not a good DAM but a superb converter.

 

Woody

Link to post
Share on other sites

Here is one purple fringe, (shoulder of the guy holding X1) noctilux 0,95 + M9 at dealer meeting.

—LR conversion—

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

Link to post
Share on other sites

The purple fringing is due to overfill of the pixels of the sensor with these high speed lenses.

 

There is a simple fix........use capture one pro as your raw converter and click on the purple fringing tab. The problem disappears immediately.

 

Capture One is still the best raw converter out there IMHO. Not a good DAM but a superb converter.

 

Woody

 

I do not have Capture 1 Pro and will have a look at it.

I do have the Noctilux 1.2, the first version of the Noctilux f1.0 as well as the 58 Noct Nikkor 58/1.2 as well as the 50/1.4 aspherical and I have tried out the 24/1.4 asph at a Leica shop in town.

The strongest purple fringe is visible with the 0.95 at full aperture as well as at f 1.4. The f 1.0 and the f 1.2 show a lesser fringe of the same subject at full opening. The two 1.4 lenses do not show anything close to these fringes - if anything at all - with the same subjects (bare tree branches against sky) and full opening.

Why does pixel overfill not show with some lenses when other lenses do? Is the light volume at f 1.4 not identical from lens to lens?

I am really in a pickle and have e-mailed Leica asking this question. I am eagerly awaiting the reply and in the meantime ordered ND filter for my old Noctilux f1.

Teddy

Link to post
Share on other sites

The lenses that have the best micro-contrast/frequency response are most affected because the level difference between adjacent pixels is the highest. This includes most of the newest designs. In my experience the Summilux 24 and Summilux 50 asph show quite strong purple fringing as well.

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...