Skip to main content
Adobe Photoshop Family

427 Messages

 • 

7.7K Points

Wed, May 2, 2012 4:23 PM

Solved

Lightroom 4.1 RC2: Artefacts when using shadows, clarity and image warp (lens corrections)

Just to make this into an "official" problem: There are strange artefacts when using shadows, clarity and image warp (lens corrections).

Details here:
http://forums.adobe.com/thread/997568...
http://forums.adobe.com/thread/995958...

Also applies to ACR 6.7 final, which shows the same artefacts for LR-images edited in Photoshop (rendering using photoshop's ACR).

P.S. May be related to http://feedback.photoshop.com/photosh... but I think they are two different/distinct problems (however, both seem to be introduced with changes in clarity in RC2).

Responses

427 Messages

 • 

7.7K Points

9 years ago

A very faint and "thin" version of the artefacts can be seen when no lens correction is applied at all. It can be seen most clearly at high contrast edges.

Here is an example (100% crop from a larger picture):

Image #1: Adobe defaults, no manual or profile lens corrections, no clarity.
Image #2: Plus clarity +100, you can see the faint "thin" artefacts already
Image #3: Plus manual lens correction rotation +0.1, the artefacts become "full-blown"





Champion

 • 

677 Messages

 • 

8.7K Points

Might be a limitation of Clarity.

427 Messages

 • 

7.7K Points

Could be... but the artefacts in the second image look "funny". They art not halos or the like, but "jagged" structures with alternating dark and light lines in one-pixel intervals. That is not the artefact I would expect from a clarity limitation.

130 Messages

 • 

2K Points

I can see the same artifacts, but it only appears where there is chromatic aberration and/or fringing present in the image. It looks like Clarity is being applied to the image prior to CA and/or Defringe removal, because you can still see it with these two tools enabled. The high Clarity setting to seems to amplify the CA.

I sure hope the fix for the original problem will remove or at least reduce this artifact.

3 Messages

 • 

92 Points

9 years ago

Applying lens profile corrections is producing very strange artifacts on some hard contrasty edges

This reply was created from a merged topic originally titled
Lightroom: Artifacts produced by lens profile correction tool.

2 Messages

 • 

70 Points

9 years ago

Lightroom 4.1RC2 (Process version 2012)
As above, but there's more going on than just Lens Correction. Using just the Basic Panel for adjustments (everything else zeroed) there is still this hard edge high contrast artifact. Lens Correction certainly dramatically adds to the effect.

Adjust a photo using Process version 2010 then select Process version 2012
(Camera Calibration Panel.) Compare the high contrast edges in the same adjusted photo with Process version 2012 and Process version 2010.

130 Messages

 • 

2K Points

9 years ago

I think you are seeing the difference between PV2010 's Develop settings and PV2012 "automatic" White and Black point settings. PV2012 shows more detail in the shadows and highlights, which is not a defect. It's just accentuating the lens defects.

Try this:

Adjust the image file using only PV2010 Basic controls and everything else turned off (zero'd as you say). Now create a virtual copy, change the copy to PV2012, and adjust the Basic controls so it looks as close as possible to the PV2010 image. When done the two Histograms should look virtually identical

Do you still this "hard edge high contrast artifact" in the PV2012 image with no other adjustments (i.e. No Lens Corrections tools) applied?

2 Messages

 • 

70 Points

9 years ago

Thanks Todd.

I did as you suggested and experimented a bit. There was very little difference with the high contrast edges between PV2010 and PV2012 with or without Lens Corrections using a baseline image. But like LRusser24 I obtained similar results (I'll call it the barber pole effect) when applying Clarity with or without Lens Corrections (distortion and CR) applied.

Attached are two screen captures (100% crop in LR) including the settings panel.

Left is PV2012 w/Lens Correction/Clarity 0.
Right is PV2012 w/Lens Correction/Clarity 50.
Clarity set at 50 exaggerates the artifacts, but I was seeing those effects at Clarity 10.

130 Messages

 • 

2K Points

9 years ago

As I already said:

I can see the same artifacts, but it only appears where there is chromatic aberration and/or fringing present in the image. It looks like Clarity is being applied to the image prior to CA and/or Defringe removal, because you can still see it with these two tools enabled. The high Clarity setting to seems to amplify the CA.

When LR builds the preview or export image it applies the Develop settings using several operations and several bitmaps, which are then merged to create the final processed output. What I think is happening is that the Clarity processing uses a bitmap that does NOT have any CA settings applied to it. This accentuates the CA (i.e. fringing), leaving halo like artifacts even after CA processing is applied.

LR3 'Fill' tool creates similar halo artifacts perhaps for the same reason, but we all assumed this was corrected in LR4.

427 Messages

 • 

7.7K Points

9 years ago

LR 4.1 final and ACR 7.1 final: The "thick" artefacts when using lens corrections are gone, but the "thin" variant shown in my post above are still there. Note: The artefacts still change shape when changing lens correction parameters, but they always stay "thin".

I am slightly disappointed. However, the "thin" variant is probably visible only in 100% view on monitor. I am not sure whether it is visible in normal cases, e.g. prints.

Employee

 • 

629 Messages

 • 

11.5K Points

9 years ago

This is a limitation of the current technology, a tradeoff we had to make to keep performance reasonable (otherwise to use the Highlights, Shadows, or Clarity sliders would be several times slower and use a lot more memory ...)

Champion

 • 

677 Messages

 • 

8.7K Points

Can you elaborate a bit, please? Under what circumstances do these limitations arise? Generally, I don't see these artefacts. Is this when Highlights, Shadows, or Clarity are pushed to far, when there's purple fringing on the edge or a combination of both?

Employee

 • 

629 Messages

 • 

11.5K Points

Dorin, generally this can happen with strong edges (e.g., dark branches against a bright sky), when used in conjunction with strong settings of Highlights, Shadows, and/or Clarity. The tone mapping methods behind these controls are edge-aware in the sense that they try to minimize halos across strong edges, as you'd expect to see if you were to try doing local dodging/burning with a brush. The underlying masking technology to minimize these halos is very complex and expensive, so we had to make some tradeoffs to get performance to a reasonable level in an on-the-fly, parametric editing system.

946 Messages

 • 

13.8K Points

The "on the fly" part is why we really need a progressive rendering system, so we don't have to make those sorts of trades if we don't want to. We used to have "pixel doubling" and detail panel settings applied later, but these have been removed. I'd like to see them back with a slider for the user to decide just how "on the fly" the renderings have to be.

Employee

 • 

629 Messages

 • 

11.5K Points

Unfortunately, such a progressive system would not help this case.

130 Messages

 • 

2K Points

9 years ago

Thank you Eric, I understand and appreciate the tradeoff concerning maintaining LR's real-time operating performance (screen image building), but what about output image building?

Would it be possible to incorporate changes for better imaging during Export, Edit In, Print, and other output operations? I think most users wouldn't mind waiting a bit longer for their final output to be processed, especially to achieve the best results. I know this may cause complaints about screen imaging not matching the output, but we're talking very small artifacts. IMHO that is also a justifiable limitation of current technology “tradeoff" that most users would accept.

This is just a suggestion for improving an already outstanding product, my compliments to you and the rest of the LR team.

Employee

 • 

629 Messages

 • 

11.5K Points

9 years ago

Hi Todd,

Indeed this is something we're considering. Thanks.

Eric

7 Messages

 • 

154 Points

8 years ago

When activating lens profile correction and when i change my process from 2010 to 2012 and using the shadow recovery slider above +20 :
the black area close to white area are becoming jagged and stripped whithin the black area around the white
eg .A white texte on a black surface

My Camera is Nikon, and this apend for any camera i had



This reply was created from a merged topic originally titled
ACR: Jagged edge from process 2010 to 2012 with lens profile correction.

5 Messages

 • 

112 Points

8 years ago

This issue is going to be hard to explain but I will give it a shot. I recently upgraded to Lightroom 4.3. After making adjustments to a photograph in Lightroom, I press CMD+E to open the photo in Photoshop. But when the photo opens, it has weird artifacts along the edges of the subjects within the photo. So, alternatively, I export the photo to my desktop and then open it with Photoshop. When it opens, the artifacts aren't there. The artifacts are only there when I use the 'Photo>Edit In' command within Lightroom. When viewing the photos in Lightroom, the artifacts are not present. I am using Lightroom 4.3, Camera Raw 7.3, and Photoshop CS5.1. The artifacts can be seen on the sleeve in the uploaded photo..

This reply was created from a merged topic originally titled
Weird Color Artifacts.

Champion

 • 

677 Messages

 • 

8.7K Points

This bug has been introduced in ACR 6.7 and the release candidates of 7.1 and LR 4.1. The bug has been subsequently fixed in 7.1/4.1 final, but will never be solved in 6.7.

So, you only option is to render using Lightroom when prompted. If you don't get this prompt when hitting Ctrl+E, reset your warning suppressions in Prefs->General->Reste all warning dialogs.

5 Messages

 • 

112 Points

The 'render using Lightroom' option worked. Thank you for your help. I just spent a couple weeks cloning that crap out of 200 photos. That was a real pain. Again thanks for taking the time to help me.