Luminous Landscape Forum

Raw & Post Processing, Printing => Adobe Camera Raw Q&A => Topic started by: Peter_DL on May 15, 2012, 12:41:42 pm

Title: PV 2010 /2012 new tonal controls
Post by: Peter_DL on May 15, 2012, 12:41:42 pm
  
Just started to try to compile some related information,
from current articles and earlier discussions (as referenced below).

From left to right along the tonal scale:
PV 2010:  Blacks – Fill Light – Brightness – Recovery – Exposure.
PV 2012:  Blacks – Shadows – Exposure – Highlights – Whites.

/>  The former Exposure slider was renamed to Whites.
Still, the slider moves the White point.  Not sure though, if it is really just a rename with regard to operations in terms of linear scaling, corresponding to +/- EV camera exposure (need to check).


/>  Recovery and Fill Light were replaced by improved functions called Highlights and Shadows.  
With the new Highlights control there is some automatic Highlight recovery going on, even without moving the slider away from zero, or using the Auto button.
With the new Shadows slider in PV 2012 its effect got more limited to the darker tones, while applying an improved algorithm to brighten without posterization.

/>  Blacks is called Blacks again, now featuring an auto-calculated Black point at default zero setting.
Still, the slider moves the Black point. Not sure though about possible changes under the hood with regard to operations in terms of applying a linear offset (need to check). Interestingly, the new Blacks slider was shown to bear a reduced side effect on color saturation.

/>  Former Brightness and Exposure sliders were hybridized to the new Exposure slider,
which now mainly controls the midtones, but also moves the White point.  It is to note that already at default zero setting* the highlights are compressed, and further with positive settings to brighten the image.

/>  The Contrast slider is now scene-dependent, offsetting its operational midpoint depending on whether you are editing a low key or high key image.


*PV 2010's default settings had Brightness +50, Contrast +25, Blacks +5, and a "medium contrast" Point curve applied.  With PV 2012, results are quite similar with all the sliders left at zero now, and Point curve = Linear.  The deviations are due to automatic Highlight recovery, and the auto-Black-point functionality, which are always enabled behind the scenes.
Anyway, the default settings impose an "S" curve on the tones, which already compresses highlight details [which is probably the main reason why some of us liked to start with a linear, flat, scene-referred rendition in the past. A subject on its own, I guess].

All six tonal controls in PV 2012 are image adaptive. They auto-adjust their behavior internally based on image content, just like Recovery and Fill Light (and also Clarity) already did with PV 2010. In PV 2012 this idea was extended to the rest of the central Basic controls from Exposure to Blacks.


Comments and additions are welcome.

Regards, Peter


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Charles Cramer, Tonal adjustments in the age of Lightroom 4
http://www.luminous-landscape.com/techniques/tonal_adjustments_in_the_age_of_lightroom_4.shtml

Martin Evening, Extreme contrast edits in Lightroom 4 and ACR
http://www.dpreview.com/articles/1205103502/extreme-contrast-edits-in-lightroom-4-and-acr-7

Why "0" should be Zero
http://forums.adobe.com/message/4289492#4289492
http://forums.adobe.com/message/4128876#4128876
http://forums.adobe.com/thread/948951

ETTR, Blacks & Exposure settings vs. Point Curve controls (PV 2010)
http://www.luminous-landscape.com/forum/index.php?topic=57177.0

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late edit: cancelled some lines for archival purposes
Title: Re: PV 2010 /2012 new tonal controls
Post by: Tim Lookingbill on May 18, 2012, 05:25:45 pm
Another thorough and concise tome of info on an important subject for digital photographers.

Nice write up, Peter. Thanks.

Took the entire afternoon to check out all those links but it was worth it because it tells me a wide range of cameras record scenes pretty much similar to one another no matter their price tag. I have to deal with same tonal mapping issues with my old $500 Pentax K100D PEFs whether with PV2003 and PV2010 in CS3 and CS5 respectively.

I used to use a Stouffer gauge back in prepress darkroom days in the '80's and I noticed in the Charles Cramer article the distribution differences from the spikes representing the mid to highlights compared to the shadows which show no separation between the steps (visually looking at the tones) even though it's there.

It would be great to understand why this is as a way to define some repeated pattern that could be compensated for to guide our adjustments without all the "zeroing" of default settings. PV2012 is a marked improvement especially evident in Martin Evening's backlit column demo. Those are some nasty halos I've become quite familiar with.

What I'm surprised is never covered in those articles is the mysterious nether regions of just exactly where absolute black resides (and shown on the display) and how the tones just next to it are affected by Fill, Black, Linear Point Curve slide to the right and most especially both Shadow and the far left triangle adjust in the Parametric Curve.

For instance in Charles Cramer's expose for clouds backlit forest shot all those brightened up trees could be even more defined by using the Parametric Shadow curve to isolate the edges of those trees and still keep the soft foggy look. The thing is similar images in my experience would show RGB readouts close to 5,5,5 on the edges of those trees but the Parametric Shadow curve seems to be able to pull incredible separation even from tones close to black I couldn't accomplish with any other tool.
Title: Re: PV 2010 /2012 new tonal controls
Post by: Schewe on May 18, 2012, 06:16:16 pm
/>  The former Exposure slider was renamed to Whites.

snip

/>  Former Brightness and Exposure sliders were hybridized to the new Exposure slider,
which now mainly controls the midtones, but also moves the White point.  It is to note that already at default zero setting* the highlights are compressed, and further with positive settings to brighten the image.

These two statements conflict...

In point of fact, Exposure was not renamed Whites...Whites is a new tone control specifically designed to fine tune the placement of the white clip point on top of Exposure. So, the first statement is wrong while the second is the correct description of the new Exposure.
Title: Re: PV 2010 /2012 new tonal controls
Post by: bjanes on May 18, 2012, 09:53:10 pm
These two statements conflict...

In point of fact, Exposure was not renamed Whites...Whites is a new tone control specifically designed to fine tune the placement of the white clip point on top of Exposure. So, the first statement is wrong while the second is the correct description of the new Exposure.

I agree that Charles Cramer's post is masterful and very useful. In my own analysis of PV2012 I used a 40 step wedge, whereas Charles used a 20 step wedge. In the 40 step wedge the steps are in 0.3 optical density decrements, so 3 steps equals 1 f/stop. The values of the wedge are shown below, where step 1 has an OD of 0.05, placing it at the values shown. Step 8 is neutral gray.

(http://bjanes.smugmug.com/Photography/ACR7/i-Kg8nSL9/0/O/StoufferValues.png)

I exposed so that step one was just short of clipping in the green channels as shown by Rawdigger.

(http://bjanes.smugmug.com/Photography/ACR7/i-t2Sxwgh/0/O/05EVHistogram.png)

On rendering the image in ACR 7 using the default settings, the highlights appear overexposed as shown in the ACR preview and histogram. Step 8 (neutral gray) is at 202 in ProPhotoRGB, whereas it should be around 98. As Charles suggests, one should set the midtones with the exposure slider, and this required a negative exposure value of -1.65 EV.

(http://bjanes.smugmug.com/Photography/ACR7/i-vBf3fxP/0/O/05ACR7ExpMinus165.png)

The highlights are too dark and the Whites slider can be used to set step 1 to the nominal value. The highlight control extends too far down the tonal scale and affects the midtones. This necessitates an adjustment of the midgray as shown.

(http://bjanes.smugmug.com/Photography/ACR7/i-wwMTqkk/0/O/05LinearizedFirstApprox.png)

The quarter tones are too light and these can be adjusted with the contrast control, which has minimal effects on the midtones and whites. Several iterations are necessary to get approximate values. This results in an approximately linear tone curve.

(http://bjanes.smugmug.com/Photography/ACR7/i-MjWQZZB/0/O/05linearizedD.png)

One can do further analysis with Imatest.

(http://bjanes.smugmug.com/Photography/ACR7/i-xjJwzNv/0/O/ExposureLinGraph.png)

With PV2010 a linear curve is more easily obtained by setting the point curve to linear and the sliders on the main tab all to zero.

(http://bjanes.smugmug.com/Photography/ACR7/i-nXLQtNW/0/O/PV2010LinGraph.png)

For ETTR exposures it is important that negative exposure to normalize the image are linear, and Eric Chan has stated in a previous post that this is the case. However, increasing the exposure rolls off the highlights so as to prevent clipping. This is shown in the composite graph below, using the same raw file as before. The adjustment is essentially linear except for the highlights.

(http://bjanes.smugmug.com/Photography/ACR7/i-z3M5Tsc/0/O/ExposureB.png)

Here are similar graphs for the highlight, whites and contrast controls.

(http://bjanes.smugmug.com/Photography/ACR7/i-cTzkjqq/0/O/Highlights.png)

(http://bjanes.smugmug.com/Photography/ACR7/i-bbMbHPW/0/O/Whites.png)

(http://bjanes.smugmug.com/Photography/ACR7/i-ZtKGcxP/0/O/Contrast.png)

Regards,

Bill





Title: Re: PV 2010 /2012 new tonal controls
Post by: stamper on May 19, 2012, 04:06:08 am
I didn't think that the human eye could see 40 steps so 20 would be a more reasonable representation? The problem with all these charts is that you don't remember them when you are processing an image? Charles article would be a more practical workflow, imo. :)
Title: Re: PV 2010 /2012 new tonal controls
Post by: Bart_van_der_Wolf on May 19, 2012, 05:35:44 am
I agree that Charles Cramer's post is masterful and very useful. In my own analysis of PV2012 I used a 40 step wedge, whereas Charles used a 20 step wedge.

Hi Bill,

Thanks for an excellent analysis and I'm glad you were also inspired by Charles Cramer's article. The added precision of finer step density increments allows to make a more accurate analysis of the 'cross-talk' between the sliders, requiring to go back and forth between controls for a more targeted result, and it allows a more detailed/accurate adjustment of the different controls.

It also demonstrates something that Christian Bloch also mentioned in the context of preparing HDR bracketed exposures, PV2012 requires a negative 'exposure' setting for starters for a more 'quasi-linear' tonecurve, but PV2010 allows a much easier route for that specific application (which requires reconstruction/calibration of the bracketed tonecurve with a glare component in each bracket). PV2012 is great for a creative approach (including exposure blending), but a nightmare for the more controlled types of photography, e.g. reproduction and somewhat scientific work which requires predictable (calibrated) response and linear tonecurves.

The only thing I missed in your post is which Camera calibration type your used. In LR I usually start with "Camera Neutral" instead of "Adobe Standard" because traditionally the color response for Canon cameras sucked. It would be interesting to find out how much of an influence, if any, that calibration choice has on overall tonality, besides the obvious effect it should have on color reproduction.

Again, thanks for a great contribution.

Cheers,
Bart
Title: Re: PV 2010 /2012 new tonal controls
Post by: bjanes on May 19, 2012, 08:41:06 am
I didn't think that the human eye could see 40 steps so 20 would be a more reasonable representation? The problem with all these charts is that you don't remember them when you are processing an image? Charles article would be a more practical workflow, imo. :)

The 40 steps with a Dmax of 4.0 are necessary to capture the full DR of current cameras, covering a DR of 13 stops. For rendering of an image with high DR one would have to use tone mapping to compress the image to something that could be visualized on screen or a print. One does not have to use all 40 steps. I used only the first 30 for my analysis. The 20 (actually 21) step wedge has a DMax of only 3.0 for a DR of 10 stops.

Charles' article and approach is better for visual editing of images in ACR/LR, but my intent was to quantify what he was seeing on the histogram.

Regards,

Bill
Title: Re: PV 2010 /2012 new tonal controls
Post by: bjanes on May 19, 2012, 08:55:44 am
Thanks for an excellent analysis and I'm glad you were also inspired by Charles Cramer's article. The added precision of finer step density increments allows to make a more accurate analysis of the 'cross-talk' between the sliders, requiring to go back and forth between controls for a more targeted result, and it allows a more detailed/accurate adjustment of the different controls.

Thanks for the kind words.

It also demonstrates something that Christian Bloch also mentioned in the context of preparing HDR bracketed exposures, PV2012 requires a negative 'exposure' setting for starters for a more 'quasi-linear' tonecurve, but PV2010 allows a much easier route for that specific application (which requires reconstruction/calibration of the bracketed tonecurve with a glare component in each bracket). PV2012 is great for a creative approach (including exposure blending), but a nightmare for the more controlled types of photography, e.g. reproduction and somewhat scientific work which requires predictable (calibrated) response and linear tonecurves.

With PV2010 and "linear" ACR settings one does get linear results and this enables one to produce a scene referred image using the method (http://www.color.org/scene-referred.xalter) outlined by the ICC. It is really a nightmare to get such results in PV2012. Fortunately, Adobe was wise to retain PV2010 and Jeff Schewe indicated that future versions will also retain it.

The only thing I missed in your post is which Camera calibration type your used. In LR I usually start with "Camera Neutral" instead of "Adobe Standard" because traditionally the color response for Canon cameras sucked. It would be interesting to find out how much of an influence, if any, that calibration choice has on overall tonality, besides the obvious effect it should have on color reproduction.

I used the Adobe Standard calibration for my work. One could look at the tone curve in the DNG profile editor, but that is for another day.

Regards,

Bill
Title: Re: PV 2010 /2012 new tonal controls
Post by: paul_o on May 19, 2012, 09:25:34 am
I really like the tonal controls of the new ACR.  The one troubling area is when I want to use to new controls on images that previously worked on with PV 2010.  In some cases, when I update to PV 2012 the tonal changes are dramatic.  I’ve found it easier to use the original image and start from scratch. Except that some images have had significant spot removal, which now needs to be redone. It would be desirable to be able to retain the effect of some tools when converting to PV 2012.   Ideally (for me) it would be desirable to be able to have all the basic sliders set as close as possible to retain the tones that were set in PV 2010 and then be able to use the new PV 2012 to make additional fine-tuning adjustments.
Is anyone else having this issue? 
Regards,
Paul
Title: Re: PV 2010 /2012 new tonal controls
Post by: Tim Lookingbill on May 19, 2012, 11:36:17 am
Will someone address the reasons behind the lack of definition and separation of the steps below middle gray compared to above middle gray on the Stouffer Gauge?
Title: Re: PV 2010 /2012 new tonal controls
Post by: Bart_van_der_Wolf on May 19, 2012, 11:38:44 am
Will someone address the reasons behind the lack of definition and separation of the steps below middle gray compared to above middle gray on the Stouffer Gauge?

Hi,

Caused by gamma adjustment + noise?

Cheers,
Bart
Title: Re: PV 2010 /2012 new tonal controls
Post by: Tim Lookingbill on May 19, 2012, 11:40:10 am
I really like the tonal controls of the new ACR.  The one troubling area is when I want to use to new controls on images that previously worked on with PV 2010.  In some cases, when I update to PV 2012 the tonal changes are dramatic.  I’ve found it easier to use the original image and start from scratch. Except that some images have had significant spot removal, which now needs to be redone. It would be desirable to be able to retain the effect of some tools when converting to PV 2012.   Ideally (for me) it would be desirable to be able to have all the basic sliders set as close as possible to retain the tones that were set in PV 2010 and then be able to use the new PV 2012 to make additional fine-tuning adjustments.
Is anyone else having this issue?  
Regards,
Paul

Copy the process of one and Paste to the other. When given the Settings dialog box listing all separate panel edits click off/on what you want. Spot Removal is selectable.

Do this on a copy of the image set to Default (no edits). When pasting the settings from the original only select Spot Removal.
Title: Re: PV 2010 /2012 new tonal controls
Post by: Tim Lookingbill on May 19, 2012, 11:41:35 am
Hi,

Caused by noise?

Cheers,
Bart

I don't see noise in those shadow areas. Are you saying the physical electronic presence of noise is causing the recording of shadow detail to go flat?
Title: Re: PV 2010 /2012 new tonal controls
Post by: Peter_DL on May 19, 2012, 11:45:39 am
Post # 3 ff.
Charles' article and approach is better for visual editing of images in ACR/LR, but my intent was to quantify what he was seeing on the histogram.

Solid analysis, Bill,
many thanks for contributing it here!

If possible (with reasonably limited effort) I think it could be helpful for many of us to see the last 4 graphs (about PV 2012 Exposure, Highlights, Whites and Contrast)
in a non-log style, but gamma encoded, just like an applied Curve in a standard working space environment.

Regards,

Peter


--
Title: Re: PV 2010 /2012 new tonal controls
Post by: Bart_van_der_Wolf on May 19, 2012, 11:46:11 am
I don't see noise in those shadow areas. Are you saying the physical electronic presence of noise is causing the recording of shadow detail to go flat?

Hi,

I added something to my post, gamma adjustment. When the gamma adjustment from linear is added, there will be a compression of shadow detail to the lesser significant bits, the noisy ones. For illustration one would also need to see the linear gamma histogram, where the separation would be better.

Cheers,
Bart
Title: Re: PV 2010 /2012 new tonal controls
Post by: Tim Lookingbill on May 19, 2012, 12:07:27 pm
Hi,

I added something to my post, gamma adjustment. When the gamma adjustment from linear is added, there will be a compression of shadow detail to the lesser significant bits, the noisy ones. For illustration one would also need to see the linear gamma, where the separation would be better.

Cheers,
Bart

That makes more sense, Bart. Thanks.

That also explains the behavior I mentioned previously of the Parametric Shadow slider adjust over just increasing the Black slider or trying to tweak the Point Curve. Wonder what new adjust in PV2012 offers a similar Clarity adjust only for shadows.

The Parametric Shadow adjust works great at separating and opening up tones below 20RGB +/- in ProPhotoRGB output space. But the effect varies image to image depending on quality of detail to noise influenced by varying scene light levels and exposures.

I'ld like to thank Jeff Schewe for the Parametric Shadow curve tip he suggested a while back. It took me a while to figure out this miracle tool because it wasn't working very well due to the fact that it often requires a hefty Fill adjust (along with its unwanted saturation boost: but fixed by Contrast reduction) and going back and adding Highlight tweak in the Parametric curve. And here I was all these years thinking the Point Curve was the miracle tool.
Title: Re: PV 2010 /2012 new tonal controls
Post by: Peter_DL on May 19, 2012, 12:35:42 pm
In point of fact, Exposure was not renamed Whites...Whites is a new tone control specifically designed to fine tune the placement of the white clip point on top of Exposure. So, the first statement is wrong while the second is the correct description of the new Exposure.

Ah ok, I see,
many thanks for the pointer and clarification.

The more we find it hard to understand the philosophy behind the change and these particular new controls:

The former Exposure slider – which was a legit digital representation of camera exposure – got separated to two new controls, now with a higher and lower impact on the midtones (-> PV 2012 Exposure and Whites). Both moving the White point though, which also means less separation at this end, compared to former Exposure and Brightness.
In other words, why are PV 2012 Exposure & Whites considered to be superior to PV 2010 Exposure & Brightness ?

Regards,
Peter

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Title: Re: PV 2010 /2012 new tonal controls
Post by: bjanes on May 19, 2012, 02:44:13 pm
If possible (with reasonably limited effort) I think it could be helpful for many of us to see the last 4 graphs (about PV 2012 Exposure, Highlights, Whites and Contrast) in a non-log style, but gamma encoded, just like an applied Curve in a standard working space environment.

Peter,

I think you are asking for something like this, which is a bit easier to interpret for photographers. Exposure is in f/stops (log scale) and the pixel value is linear. Middle gray is -2.5 EV for exposure and has a ProPhotoRGB value of 98. When I get time, I will revise the other graphs.

(http://bjanes.smugmug.com/Photography/ACR7/i-rrBCmW9/0/O/05LogLinearExpPV2012.png)

Regards,

Bill
Title: Re: PV 2010 /2012 new tonal controls
Post by: mouse on May 19, 2012, 04:30:45 pm

Quote
With PV2010 and "linear" ACR settings one does get linear results and this enables one to produce a scene referred image using the method outlined by the ICC. It is really a nightmare to get such results in PV2012. Fortunately, Adobe was wise to retain PV2010 and Jeff Schewe indicated that future versions will also retain it.

Sorry to interject such a banal question into this most interesting and erudite thread.
Can I interpret this to mean that ACR7 will give one the option of working with PV2010 or PV2012?
Title: Re: PV 2010 /2012 new tonal controls
Post by: bjanes on May 19, 2012, 05:31:56 pm
Peter,

I think you are asking for something like this, which is a bit easier to interpret for photographers. Exposure is in f/stops (log scale) and the pixel value is linear. Middle gray is -2.5 EV for exposure and has a ProPhotoRGB value of 98. When I get time, I will revise the other graphs.

Replying to myself to post some more revised graphs in the format Peter requested. The contrast graph is illustrative of image adaptive editing. The contrast curves vary with exposure settings.

(http://bjanes.smugmug.com/Photography/ACR7/i-8k426Hd/0/O/HighlightsLogLiln.png)

(http://bjanes.smugmug.com/Photography/ACR7/i-zPFZqHR/0/O/WhitesLogLin.png)

(http://bjanes.smugmug.com/Photography/ACR7/i-nzjjsq3/0/O/05ContrLogLin.png)

Bill
Title: Re: PV 2010 /2012 new tonal controls
Post by: bjanes on May 19, 2012, 05:41:37 pm
Sorry to interject such a banal question into this most interesting and erudite thread.
Can I interpret this to mean that ACR7 will give one the option of working with PV2010 or PV2012?

Yes, that is right. It also offers the option to use PV2003.

Bill
Title: Re: PV 2010 /2012 new tonal controls
Post by: Peter_DL on May 21, 2012, 06:12:36 pm

With PV2010 and "linear" ACR settings one does get linear results and this enables one to produce a scene referred image using the method (http://www.color.org/scene-referred.xalter) outlined by the ICC. It is really a nightmare to get such results in PV2012...

I used the Adobe Standard calibration for my work. One could look at the tone curve in the DNG profile editor, but that is for another day.

As far as I can tell from some qualitative tests, we can still get close to a linear, scene-referred rendition by creating a custom color profile with the DNG Profile Editor with its Tone Curve set to Linear, then using Camera Raw Defaults (whether with PV 2010 or 2012) when processing the image with that custom profile selected.  Some limited deviations being due to auto-highlight-recovery and the auto-black-point functionality coming into play with PV 2012, depending on image.

As for PV 2010 the results with this approach of using a linear profile are indeed nearly identical compared to "linear" ACR settings (basic sliders zero'd and Point Curve = Linear) while using a profile with Camera Raw Default Tone Curve... as confirmed earlier by Eric.

Regards, Peter


P.S.: Thanks again for the graphs !

--
Title: Re: PV 2010 /2012 new tonal controls
Post by: bjanes on May 21, 2012, 08:40:00 pm
As far as I can tell from some qualitative tests, we can still get close to a linear, scene-referred rendition by creating a custom color profile with the DNG Profile Editor with its Tone Curve set to Linear, then using Camera Raw Defaults (whether with PV 2010 or 2012) when processing the image with that custom profile selected.  Some limited deviations being due to auto-highlight-recovery and the auto-black-point functionality coming into play with PV 2012, depending on image.

As for PV 2010 the results with this approach of using a linear profile are indeed nearly identical compared to "linear" ACR settings (basic sliders zero'd and Point Curve = Linear) while using a profile with Camera Raw Default Tone Curve... as confirmed earlier by Eric.

Peter,

I compared the PV2010 linear (linear point curve, sliders on main tab all zero) with a custom profile with a linear tone curve created in the DNG profile editor and defaults in PV2012. The results are nearly the same except for some divergence in the highlights and a bit greater divergence in the shadows, consistent with your predictions. It is really easier to use the PV2010 method and not have to make a custom profile and worry about highlights and shadows. A log-log plot is necessary to obtain a linear curve with gamma encoded images.

Regards,

Bill
Title: Re: PV 2010 /2012 new tonal controls
Post by: Phil Indeblanc on May 21, 2012, 10:30:36 pm
Great posts here.  Powerful info to grasp! Nicely done!
Title: Re: PV 2010 /2012 new tonal controls
Post by: Peter_DL on May 22, 2012, 02:12:56 pm
I compared the PV2010 linear (linear point curve, sliders on main tab all zero) with a custom profile with a linear tone curve created in the DNG profile editor and defaults in PV2012. The results are nearly the same except for some divergence in the highlights and a bit greater divergence in the shadows, consistent with your predictions. It is really easier to use the PV2010 method and not have to make a custom profile and worry about highlights and shadows.

Bill,

When creating a linear custom profile by means of the Profile Editor, one interesting observation by the way was
that the initial Tone Curve as introduced by the Base Profile = Adobe Standard is noticeably different from Tone Curve set to Camera Raw Default.  The latter and the resulting profile are supposed to be the more correct choice for linearizing PV 2010 the old way (w/ basic controls zero’d and Point Curve Linear). It also minimizes the difference compared to PV 2010 or PV 2012 @ default settings while using a linear custom profile.  It may depend though on the camera and the corresponding Adobe Standard profile, however, it seems that we have always been in need of a custom profile for the given task.

Regards, Peter

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Title: Re: PV 2010 /2012 new tonal controls
Post by: Peter_DL on May 23, 2012, 02:51:02 pm
  ... to compile some related information,
from current articles and earlier discussions (as referenced below).

Just to add it to the list:

Adobe’s help page on this subject w/ some basic content at least (http://helpx.adobe.com/content/help/en/creative-suite/using/make-color-tonal-adjustments-camera.html#adjust_tone).
Some further image examples on PV 2012 tonal controls along this LR4 review by Amadou Diallo (http://www.dpreview.com/articles/7481161037/lightroom-4-review/print#develop1).

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Title: Re: PV 2010 /2012 new tonal controls
Post by: bjanes on May 23, 2012, 06:32:40 pm
When creating a linear custom profile by means of the Profile Editor, one interesting observation by the way was
that the initial Tone Curve as introduced by the Base Profile = Adobe Standard is noticeably different from Tone Curve set to Camera Raw Default.  The latter and the resulting profile are supposed to be the more correct choice for linearizing PV 2010 the old way (w/ basic controls zero’d and Point Curve Linear). It also minimizes the difference compared to PV 2010 or PV 2012 @ default settings while using a linear custom profile.  It may depend though on the camera and the corresponding Adobe Standard profile, however, it seems that we have always been in need of a custom profile for the given task.

For my camera the Adobe Standard profile and its tone curve produce linear results with PV2010 when the basic controls are zeroed and the point curve is set to linear as shown below. The departure from linearity in the deep shadows is likely due to flare light. It certainly does no harm to make a custom curve in the DNG profile editor using the linear tone curve option which overrides whatever tone curve is present in the base profile.

(http://bjanes.smugmug.com/Photography/ACR7/i-nXLQtNW/0/O/PV2010LinGraph.png)

In my experience it is very difficult to produce linear results with PV2012, consistent with Bart's observations. Have you succeeded?

Regards,

Bill
Title: Re: PV 2010 /2012 new tonal controls
Post by: Peter_DL on May 24, 2012, 12:35:04 pm
For my camera the Adobe Standard profile and its tone curve produce linear results with PV2010 when the basic controls are zeroed and the point curve is set to linear as shown below. The departure from linearity in the deep shadows is likely due to flare light.

That's a quite perfect result, Bill.

Out of interest, does the Adobe Standard profile for your camera show any difference between Tone Curve = Base Profile vs. Camera Raw Default in the DNG Profile Editor ?
 
 
In my experience it is very difficult to produce linear results with PV2012, consistent with Bart's observations. Have you succeeded?

For my qualitative purposes, and also in view of the close match seen with the graph in your previous post # 22, I’d say that the linear results with PV 2012 are reasonably okay.  We could argue that an (auto-)black-point setting does not per se break linearity in the sense of y= ax + b (although the new implementation of Blacks may have overcome such simple math), and further that the auto-highlight recovery feature seems to act quite gentle, and is virtually without effect with a properly exposed image.  Just as you stated "The results are nearly the same except for some divergence in the highlights and a bit greater divergence in the shadows".

Regards, Peter

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Title: Re: PV 2010 /2012 new tonal controls
Post by: terrywyse on September 03, 2012, 11:24:06 am
I agree that Charles Cramer's post is masterful and very useful. In my own analysis of PV2012 I used a 40 step wedge, whereas Charles used a 20 step wedge. In the 40 step wedge the steps are in 0.3 optical density decrements, so 3 steps equals 1 f/stop. The values of the wedge are shown below, where step 1 has an OD of 0.05, placing it at the values shown. Step 8 is neutral gray.

Not that it matters but....0.30 density = 1 f/stop. The scale in question has increments of 0.10 which is 1/3 stop.....so 3 steps = 1 f/stop as you stated.

I'm curious how the Stouffer transmission scale was photographed. You used a transparency/slide viewer? What sort of surround did you use to reduce flare? Black/opaque, gray or no surround?

Very informative by the way....thanks for doing all the hard work

Terry
Title: Re: PV 2010 /2012 new tonal controls
Post by: bjanes on September 03, 2012, 02:31:01 pm
I'm curious how the Stouffer transmission scale was photographed. You used a transparency/slide viewer? What sort of surround did you use to reduce flare? Black/opaque, gray or no surround?

Very informative by the way....thanks for doing all the hard work

I used a 5000K light box formerly used for viewing transparencies (left over from my film days). I did replace the magnetic ballast with electronic to avoid 60hz flicker. Masking off the surround is critical and I used exposed x-ray film supplied by a radiologist friend. It is thin and quite opaque, but is getting harder to get since digital is also taking over medical imaging.

Regards,

Bill