Jump to content

SL2+lens w/minimal chr.ab.


Genoweffa

Recommended Posts

Advertisement (gone after registration)

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!

 

This an unedited shot (converted to jpeg). SL2+zeiss 21 ze

Light was behind me a bit to the left. 

Branches @ top of pic....do you know of any wide lens that would not give me such ch.a. in that scene?

Edited by Genoweffa
correction
Link to post
Share on other sites

2 hours ago, Genoweffa said:

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!

 

This an unedited shot (converted to jpeg). SL2+zeiss 21 ze

Light was behind me a bit to the left. 

Branches @ top of pic....do you know of any wide lens that would not give me such ch.a. in that scene?

The SL16-35 and SL24-90 are good, showing none/minimal of miscoloring against highlights. I suspect the soon-to-come SL21mm-APO to be outstanding. Regarding Sigma wide angle lenses, make a search a la 'sigma art wide angle chromatic aberration'. 

Link to post
Share on other sites

Unfortunately this is not simply a lens issue, nor is it just chromatic aberration. It is an interaction between lens, sensor and demosaicing algorithms. Nor has it got much to do with APO correction, which is solely in the plane of focus, whilst LOCA is by definition in the OOF areas against the high-contrast (sharp) edges - and is not included in the APO designation (although Leica does pay attention to the corrections outside the plane of focus). Thus the higher resolving the lens, the higher the chance of purple edges. Also, the major component of purple fringing on shorter lenses is mainly a sensor issue - blooming at the high contrast edge. Thus -again- the higher resolving the lens, the sharper the contrast at pixel level, the more blooming. 
So there is no guarantee that a APO Summicron 21 would show less fringing, especially if Leica decides to go for maximum edge microcontrast and resolution  

This article gives a concise explanation:

https://www.photoreview.com.au/tips/shooting/colour-fringing-explained/

Having said that, the final word on this complex phenomenon is not yet spoken. In practice it is a matter of experimenting whether a particular lens on a particular sensor will produce more purple edges or less (no quality lens is free). I prefer to ignore it and use the correction slider during post processing. Much less of a headache.

  • Like 3
  • Thanks 3
Link to post
Share on other sites

Just to elaborate:

Here is a screenshot from the Imatest article on the subject matter, they are not the least of  experts and suggest that it is not a lens error at all.

*screenshot under Zitatrecht

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!

  • Like 2
  • Thanks 2
Link to post
Share on other sites

1 hour ago, jaapv said:

Just to elaborate:

Here is a screenshot from the Imatest article on the subject matter, they are not the least of  experts and suggest that it is not a lens error at all.

*screenshot under Zitatrecht

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!

If this is true, why does this seem to happen more with some lenses than others? I notice it more with wideangle lenses. Could it be that these type of scenes often have a high dynamic range with lots of small detail which are more prone to this effect? At least it is relatively easy to remove in post.

Link to post
Share on other sites

Advertisement (gone after registration)

It depends on the resolution/micro-contrast of the lens and the resolution of the sensor among other things. I suspect but have no proof that telecentricity is also a factor. I also suspect that the explanation of Imatest is too narrow and that LoCA has some influence albeit depending on focal length. That again depends on the chromatic correction of a lens in the OOF area.

This is not a straightforward single-cause phenomenon. 

Link to post
Share on other sites

8 hours ago, jaapv said:

It depends on the resolution/micro-contrast of the lens and the resolution of the sensor among other things. I suspect but have no proof that telecentricity is also a factor. I also suspect that the explanation of Imatest is too narrow and that LoCA has some influence albeit depending on focal length. That again depends on the chromatic correction of a lens in the OOF area.

This is not a straightforward single-cause phenomenon. 

I think that also depends how light and what kind of light falls on/behind the subject

Link to post
Share on other sites

I looked thru my older pics...have a very similar shot of the same location with sl2+ve24-70@24mm

does not look that bad as previous one...

 

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

8 hours ago, Genoweffa said:

I looked thru my older pics...have a very similar shot of the same location with sl2+ve24-70@24mm

does not look that bad as previous one...

 

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!

After using the SL24-90 since it became available, and on various Lumix (S1, S1R, S5) and Leica bodies (SL, SL2, SL2-S), I have hardly seen any discolouring effect at all. Other lenses are very prone to this effect; SL24-90 and SL16-35 are exceptions. Another lens hardly showing discolouring against highlights is SL35-APO.

  • Like 2
Link to post
Share on other sites

In my experience this does in fact have a lot to do with the lenses as well. For example, I see this very clearly in the Sigma 35mm f2 DG DN, but not at all in the Leica 35mm APO Summicron. The Leica 35mm Summilux ASPH FLE M lens also shows it worse than the 35mm APO. Whether it is "fringing" or some other optical issue, it does seem to be driven by the lens to a certain degree. If it is not fringing per se, then perhaps it is the fact that the 35mm APO has so much more contrast and resolution than the other two lenses do wide open...I am not sure. But in my experience the APO Summicrons have been nearly completely free of this problem, and it is one of their best improvements over other lenses. That, along with near total freedom from longitudinal chromatic aberration. Of course the sharpness is extremely high, but sharpness is not very helpful if the out of focus areas are tinged with green and magenta, and all the high contrast edges glow with blue or red light.

  • Like 1
Link to post
Share on other sites

1 hour ago, Stuart Richardson said:

In my experience this does in fact have a lot to do with the lenses as well. For example, I see this very clearly in the Sigma 35mm f2 DG DN, but not at all in the Leica 35mm APO Summicron. The Leica 35mm Summilux ASPH FLE M lens also shows it worse than the 35mm APO. Whether it is "fringing" or some other optical issue, it does seem to be driven by the lens to a certain degree. If it is not fringing per se, then perhaps it is the fact that the 35mm APO has so much more contrast and resolution than the other two lenses do wide open...I am not sure. But in my experience the APO Summicrons have been nearly completely free of this problem, and it is one of their best improvements over other lenses. That, along with near total freedom from longitudinal chromatic aberration. Of course the sharpness is extremely high, but sharpness is not very helpful if the out of focus areas are tinged with green and magenta, and all the high contrast edges glow with blue or red light.

Tracing through the images with SL35-S on SL2-S, including numereous candidates for miscoloring against highlights, I haven't found a single one showing this behaviour. The (medium format) S-lenses, being bitingly sharp, are prone to miscoloring (on S006 and S3). Doesn't prove anything, but I do agree that the lens is part in this. 

Edited by helged
  • Thanks 1
Link to post
Share on other sites

That image was taken with the Zeiss 21mm Classic model. I have the original Contax 21 Distagon, and I suspect it would show the same blooming.

However I now use the Zeiss 18mm 2.8 Milvus and the 25 1.4 Milvus and I shoot a ton of landscape all with fine tree branches on the edges of the frame, against the sky, and have yet to see any discolouring of any kind in any of the shots. 

These two lenses both have a new optical formulas from the Classic series and are terrific lenses IMO. No need to wait for the SL APO 21 or 24 Summicrons, because I don't think they can be any better. I use a S1r body.

  • Like 2
Link to post
Share on other sites

On 2/18/2023 at 11:26 AM, douglas ball said:

That image was taken with the Zeiss 21mm Classic model. I have the original Contax 21 Distagon, and I suspect it would show the same blooming.

However I now use the Zeiss 18mm 2.8 Milvus and the 25 1.4 Milvus and I shoot a ton of landscape all with fine tree branches on the edges of the frame, against the sky, and have yet to see any discolouring of any kind in any of the shots. 

These two lenses both have a new optical formulas from the Classic series and are terrific lenses IMO. No need to wait for the SL APO 21 or 24 Summicrons, because I don't think they can be any better. I use a S1r body.

Yes, I have MIlvus 18 and 25 Classic.

Looked thru past pics (18)...there is still some discolouring on pics with back/side back light on 'thin sticks' if I may call them such. With a good en face light all perfect.

Edited by Genoweffa
.
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...