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Add ability to easily fine tune highlights recovery, for example, by selecting the highlight range.

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28 条评论

  • BeO
    Top Commenter

    I support your request.

    In general, I think the highlight tool is quite good, but there are quite a few situations where it is not sufficient without a big manual effort and even then it can be tricky. And sometimes there is no data which can be recovered (typically if it is all grey) but even then something could be done...

    [anecdote: if I remember 'darktable' correctly it has a highlight reconstruction tool (better: construction) for areas which are really without data even in the raw file. This tool can yield convincing results but was a nightmare to use (for me)]

    I'd love to have something in C1 which can deal with 'no-data' specular highlights, e.g. water drops in moss or even just tiny reflections from stone or ground with reflective particles, I'm talking maybe 5-20 pixels or so which are totally out. C1's noise single pixel slider won't help because it doesn't work on this number of pixels. It does look like very digital artifacts. Granted this is only an issue for very big prints but then a lot of cleaning in PS or alike takes hours.

    It would be great to have something which blends these tiny areas into the surrounding areas, with some structure from the surrounding in it. 

    I assume this goes into the same direction as your use case, maybe it can be solved by the same solution concept. Anyway, +1 from me.

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  • john hardiman

    I think the Capture One highlights tool works well when the image suits it.  It's different to the Lighroom highlights tool (which seems to consider a highlight as something that's brighter than its surround, rather than something that's just generally bright) and both have different pro's and cons.

    I also like the highlight reconstruction tool idea but in the context of art reproductions, accuracy is most important.  In the situation I describe above, I would have made a custom ICC profile and exposed in a way that retains the highlights within the data, the problem I have is that the highlights still get clipped off when applying the custom ICC profile because the profile is built to correct colour/tone for the flat plane, but not for the 'extra' light sources in the highlights which end up clipped.

    Your scenario is similar though, the highlights you refer to are also being clipped because they are effectively from a secondary light source that wasn't exposed for, the question is whether or not there is data available to re-create them.  Having the ability to 'make up' the missing data would definitely be helpful in that scenario, if it worked convincingly.  There might be two ways to approach it, if it was a flat or smooth area like a blown out piece of sky you could guestimate the missing data based on the info in the red green and blue channels, but if it's a small area like you refer to which can be suddenly clipped in a big way, perhaps it would need a different approach?

    In the art reproduction example where the data exists, it is possible to select and recover the highlights convincingly and accurately in Capture One, however can be a fiddly manual process to get right.  Capture One is well built for making such reproductions, so a method to recover highlights accurately and appropriately in a controlled way would be excellent.

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  • Boris Tomsic

    Create a Luma Range Mask to apply the adjustment to.
    I often that using the Brightness tool works well instead.
    A further option is to create a Luma Range mask and use the Color Balance - Highlights tool

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  • john hardiman

    Thankyou Boris, those are good suggestions, but I already am using a Luma Range mask.  What I would request instead is that the Luminosity mask isn't required and that there could be quicker and easier way.  The Luma mask works based on luminosity (obviously) but I probably need  range based on 'edge of gamut'  or 'clipping' because the luma mask doesn't affect clipped colours the quite the same as clipped highlights which then adds extra steps to make it all work. The Luma range to get the white highlights fixed is different than needed to fix the coloured areas.  By extending the luma range to also fix coloured areas, it dulls down all the whites.  

    Since Capture One already does a decent job of showing which areas are clipped, surely it could also make a feature that can adjust those areas seamlessly.

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  • BeO
    Top Commenter

    Having the ability to 'make up' the missing data would definitely be helpful in that scenario, if it worked convincingly. There might be two ways to approach it, if it was a flat or smooth area like a blown out piece of sky you could guestimate the missing data based on the info in the red green and blue channels, but if it's a small area like you refer to which can be suddenly clipped in a big way, perhaps it would need a different approach?

    Maybe something like the Heal tool in C1, with the source point near the border of the blown region,or the (arguably better) impainting brush in Affinity.

    I also like the highlight reconstruction tool idea but in the context of art reproductions, accuracy is most important. 

    In the art reproduction example where the data exists, it is possible to select and recover the highlights convincingly and accurately in Capture One, however can be a fiddly manual process to get right.  Capture One is well built for making such reproductions, so a method to recover highlights accurately and appropriately in a controlled way would be excellent.

    So your case is when the highlights are not clipped off in the raw file, it is a different use case then the one I mentioned, still you have my vote!

    I'm curious about the higlight and shadow warning on color areas, I also have the feeling that it (sometimes?) works as an out of gamut warning, though I don't remember having found this in the documentation. However, why is it important to control that during editing of the image, isn't it automatically controlled by the color space conversion when exporting? Granted, the recipies lack settings for the rendering intent (and black point compensation), you have to use the preference setting for rendering intent. Do you need more control over the color compression?

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  • john hardiman

    Hi BeO,

    In my case, the highlights aren't clipped in the raw filie, but I want to edit the picture in a way that protects them with a level of control as they can easily be blown out when the remainder of the image is correctly toned.  Since I'm using a custom ICC profile with linear tone curve, they may be clipping more abruptly than the ones built into Capture One which might have more of a roll off into the highlights (I guess).  But the highlights can be clipped similarly regardless of the profile/curve if you edit that way.

    The highlights and shadow warning indicates if at least one of the channels is clipped (past your warning level), so an area can have colour but still indicate a highlights warning because one channel has crossed a limit and the colours begin to appear over saturated or washed out.

    As for colour space conversion, that's a good question since Capture One can use a perceptual conversion into the destination colour space.  I don't know all the answers and I could be wrong here, but I believe the perceptual 'compression' when converting to a working colour space such as sRGB isn't actually perceptual mapping anyway, but a relative conversion which won't map out of gamut colours back into gamut.   Exporting to a printer profile probably should be different because it has specific perceptual tables (from what I understand, that's my simplistic explanation).

    If I try what you're saying and export from Capture One, Capture One won't map the out of gamut / overexposed areas into gamut when I export the image into a working space such as Prophoto or HasselbladLstar.  I need to control them first within Capture One, then export.

     

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  • BeO
    Top Commenter

    Perceptual and relative rendering intent both are meant to put colors which are in gamut in the source color space but out of gamut in the target color space via transformation into the gamut of the target space during conversion. If I remember right perceptual moves in gamut (target) colors a little bit to make room for the out of gamut colors, and relative does not.

    Btw, do you use a C1 version which has the White slider already? (you only mentioned the Highlight slider in your request and that it affects too much of the highlights)

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  • john hardiman

    Hello BeO,

    Yes, my version (23, the latest) has the white slider, it doesn't help with the highlight fine tuning in the way I need.

    Relative rendering will effectively clip out of gamut colours, I guess you could say they are brought into gamut but really they are just brought to the edge of the colour gamut and will generally create blobs of colour in the picture with little or no variation.

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  • Brian Jordan
    Moderator

    John, Maybe you should check out the levels slider.  Not much you can't do there.  That plus the luminance curve will give you likely the finest control you can get in any application.  I'm old-school and use them far more often than I use the HDR sliders.  If you need a refresher, Capture One hosted a session earlier this week.  Video should be up on YT now.

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  • john hardiman

    Hi Brian,

    Slow response I know.  I did check the levels slider and video session too.  The levels slider couldn't help with what I needed.  I think part of the problem is that the highlights I want to control are not necessarily the brightest part of the scene, so they become hard to select manually.  White highlights are, but highlights in coloured areas still have channel/gamut clipping to bring under control while not being the brightest part of the scene.  So by the time I have selected a wide enough luminance range to affect these coloured highlights to try and bring them pleasingly into gamut, I end up affecting the white (properly exposed non-highlight) areas of the scene also, which muddies all the whites.  I hope that makes some sense to someone other then myself, apologies if it's not a technically perfect explanation.  I will be happy to show anybody from Phase/Capture One an example if needed and to further explain the request.  Essentially, I am trying to bring out of gamut highlights into range without affecting other areas in a quick and efficient way.  Since the gamut warning of Capture One seems to understand which areas I'm targeting, I'm sure there must be a solution possible, however masking manually by luminance only will target based on luminance, not clipping/gamut, and as far as I can tell these give different results.

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  • Class A

    Of course curves offer a lot of control and I personally use them all the time, but I do think that the utility of standard (tonality control, but potentially also other) sliders could be improved if one could affect their operation range. Manipulating two sliders, say one for contrast and the other for the pivot point for contrast, is just quicker than manually moving curve points around.

    I support the request but would like to see operation range control offered for practically every slider.

    Sliders could offer an "unfold" icon that allows one to make additional controls visible on demand.

    BTW, the worst are "adaptive" controls where the software figures out the operational range and effect strength based on the image content. As soon as Lightroom introduced these "smart" controls, I knew I had to find an alternative.

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  • john hardiman

    Yes, curves are great and although my request feedback on a way to target gamut clipping is a bit different, it would certainly help to have more control of curves in an efficient way.  I think I have already requested more control of curves, such as being to adjust ranges similar to Lightroom's curve sliders which just make adjustments quicker. Whatever the solution is there, the idea is to be able to target curves precisely without having to add numerous fiddly little control points (unless you want/need to).

    While on the topic (and I might just make another request for this) one suggestion I have for Capture One curves is to make it possible to interchange the Luminosity and RGB curve, so for example if you make an adjustment to the RGB curve, then realise it would be better as a luminosity curve, or if you just want to try it as another curve type, it can be time difficult to replicate a complex curve again.  Sometimes I find the best option is in between the two.  But if you could convert the original curve from normal to luminosity it would be so much easier.  So my suggestion would be to have a slider (or similar) alongside each curve which could change the proportion between normal and luminosity.  So there could still be the RGB and Luminosity curve by default, but each could be shifted towards the other in any proportion you want.  I guess the saturation slider can play a similar role, but it's not the same and this should be more elegant, especially for more technical work.

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  • Brian Jordan
    Moderator

    john hardiman I continue to follow this conversation and must confess I'm having a difficult time understanding what you're trying to do.  Any chance you can post a sample of one of the images you're talking about and shots of how you're manipulating the various curves, levels, and sliders?

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  • john hardiman

    Hi Brian,

    I've made a video which seemed easier than using pictures and text.  Please find it at the link below.

    https://1drv.ms/f/s!AiK2tv0VPgvuoR5EqZWnYTZr_mce?e=tf9sVN 

    If the link doesn't work please let me know.

     

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  • Brian Jordan
    Moderator

    john hardiman

    Hey, John.  First off, let me just clear up that I don't work with or for Capture One.  I'm just a mod here.  I try to tamp down the spam posts and thus ends my official capacity.

    That said, I'm really interested in this thread.

    I watched your video and my very first question is why aren't you using the advanced color tool?  You can very, very precisely select colors and adjust luminance, saturation, tone.  You could switch over to the Skin Tone tool and do all of the above with even more control.  

    The tools you're using are global adjustments and can only be constrained by masking.  Color selection is exactly the opposite.  Color tools use the color values as the mask.

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  • john hardiman

    Interesting, I hadn't thought of the advanced colour tool, I'll have to learn it's tricks and see what it can do, probably a lot that I don't know about.  But overall I'm not trying to adjust a particular colour, paintings can have multiple areas with multiple colours, it's more about whether it's clipped or not.

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  • Class A

    @john hardiman

    A note on terminology: Technically, "out of gamut" means that a colour cannot be represented within a given colour space. The bigger the colour space, the "wider" the gamut.

    I don't think that your coloured highlights are out of gamut; I rather suspect that the hue change is due to a profile that applies hue twisting, i.e., modifies hues along with the luminance value. Profile creators often do that to make sunsets look nicer, for example. You might thus be able to avoid the hue shifts with a different profile (that you probably would have to create yourself). An alternative would be to switch to a larger colour space (say AdobeRGB, in case you are printing).

    Unfortunately, as far as I know, C1 still does not offer a way to check whether a colour is out of gamut. Tools like Photoshop do, so you might want to employ such tools to investigate.

    You can technically recreate the (green) mask that C1 shows you when you activate the overexposure warning since that mask is just based on a simply threshold decision. If pixel values are over the threshold value, the mask is present at the location, otherwise it isn't. As you surely know, you can set the threshold value in the preferences. Therefore, you can recreate such a mask with the "Luma Range" tool. You just have to set a "brick wall" filter, that is 100% for a few highlight values and then drops off immediately to zero. A slight ramp will probably yield more pleasant results, though.

    I suspect, however, that you'll need different adjustments for the white highlights vs the coloured highlights. Perhaps you can pick them out via two different "brickwall" or "rectangular spike" luma filters, but probably not.

    While Brian's suggestion to use the advanced color tool is very useful, it does not offer a solution for how to isolate the adjustments to the white highlights from the adjustment to the coloured highlights, unless you succeed in selecting (practically) all hues with very low saturation. Such a selection would look like a small and thin doughnut.

    I believe your problem is an example for when it can be useful to have mask operations. With those, you could just adjust the whites as needed and then subtract a mask which you obtain from selecting coloured highlights you don't want to see affected (such a mask can be created with the colour editor).

    P.S.: It would be handy, to address your particular problem, if the advanced color editor tool allowed to select the affected range based on luminance as a well. The new Lightroom "point color" tool allows that (in addition to selecting the affected hue and saturation range).

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  • Brian Jordan
    Moderator

    john hardiman. Do look into this.  Color selection can be extremely precise both in tone and saturation.  Further, you can select a color then click the 3 dots at top right of the color tool and convert that selection into a mask - which you can then further restrict with a luma range mask.  Powerful stuff.  

    This video is based on an earlier version of Capture One but color selection in the Advanced Color Tool works just the same. https://www.youtube.com/watch?v=-1BxxMwatBQ.  

    This video talks about the Skin Tone tool.https://www.youtube.com/watch?v=VoYcfVBO2HE. Don't let the name fool you.  You can use the dropper tool to select any color and the tool works around that color, not just skin tones.  The biggest difference in the tools is that the advanced color tool allows adjustments of +/- 100 with a full movement of the slider.  Skin tone is more finessed.  A full movement of the slider gives only a +/- 30.  (Don't quote me on those absolute values but the comparison is accurate.). Also, the skin tone tool allows 'normalization of colors' where you can move all colors within the pie slice towards the single target color. Advanced color tool doesn't do that.

    As to selecting whites, you can do exactly as Class A mentioned.  Expand the selection pie slice to include the entire color wheel then move the saturation border way, way down.  You get whites only.  Or you can just use the eye dropper selection in the Advanced Color Tool or Skin Tone Tool to select those white areas and adjust the selection as necessary to further constrain.  Also, you can check the box at the bottom to turn everything gray scale except the area selected so you see how changes you make to the pie slice expand or contact the actual area/colors selected.

    Class A, I've purposefully avoided the "gamut" part of the conversation rather than further confuse the issue but I do agree with you.  I figured we could cross the gamut bridge once we've got the selection nailed.

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  • BeO
    Top Commenter

    john hardiman,

    Which proof profile are you using?

    If it is "no proof profile" then be cautious with the Advanced or Skin Color Editor tool because there is a bug with with color readouts, exposure warnings and histogram:

    https://support.captureone.com/hc/en-us/community/posts/14368035139485-Color-Editor-does-not-update-Histogram-Exposure-warnings-and-Color-Readouts-when-no-proof-profile-is-enabled- 

     

    Throwing in two ideas, whatever it is worth:

    In the situation I describe above, I would have made a custom ICC profile and exposed in a way that retains the highlights within the data, the problem I have is that the highlights still get clipped off when applying the custom ICC profile because the profile is built to correct colour/tone for the flat plane, but not for the 'extra' light sources in the highlights which end up clipped.

    Having seen your video,  it is not really 'flat' art reproduction if you have 3D paint blobs on the canvas, that's your problem, right?

    I never made a profile myself so this might be nonsense, but maybe you can make a profile which accounts for the light reflected by the angled parts of the subject. What I mean is you could angle the colorchart when for profile creation to catch more light, just like your angled parts in the subject does. And hopefully the subject midtones for the really flat areas are still accurate. Maybe it solves one or the other issue and/or gives you a better starting point.

    If  this idea of angled color patches would work in general, maybe you could even DIY a set of curved color patch stripes (one for each row of the current flat color chart) to have more angles available at once, like so:



    Since I'm using a custom ICC profile with linear tone curve, they may be clipping more abruptly than the ones built into Capture One which might have more of a roll off into the highlights (I guess).  But the highlights can be clipped similarly regardless of the profile/curve if you edit that way.

    Maybe it helps if you define you own highlight rolloff with the Luma curve tool. The C1 base characteristics Linear curve is meant for working with the curve tool.

    (just an example, probably a badly defined rolloff)

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  • john hardiman

    Hi Brian and Class A,

    Okay, let me try and respond in order of the conversation:.

    So when I have said 'out of gamut', perhaps I should say 'clipped' instead, where for example the red colour channel has clipped to 255 in the yellow area.  As I recall, the RGB values shown in the top center of screen  represent the RGB numbers in the selected export recipe or proofing list, to check further, I checked that the clipped areas (as shown by the exposure warning mask), were indeed clipped to 255 even when proofing to the ProPhoto colour space.

    The yellow highlights are not the result of a hue twist in the profile.  Thinking through it now, they would be the result of applying the custom ICC profile I made in Basiccolor Input.  Unlike a regular ICC profile, this is a 'reproduction' ICC profile, so white is mapped to the white as photographed in the reference chart.  So if for example the reference photo of the chart is under-exposed so that the 'white' patch looks grey, and an ICC profile is created from that, the ICC profile will map that 'grey' value back to white.  Slight under exposure is needed in the process to allow for the capture of highlights into the raw data (eg, areas brighter than the white patch which are catching more light because of the angled textures).  I hope that makes sense.  So by applying my profile to map the values correctly for the painting as a whole it also clips the highlights in the textures (as to be expected). What I am aiming to do is recover those highlights in a pleasing and easy way.  Capture One is used extensively in cultural heritage applications for art reproduction, so I can not be the only one with this question/issue!

    As for checking 'out of gamut', it seems to me that the Exposure warning in Capture One does this by checking if R G or B values exceed the set limit value in destination colour space, I've set mine to 254, seems to do the job. (Or maybe we're talking about different things?).

    'Recreating the green mask' (exposure warning).  I don't believe this can be done based on luminance values alone as the exposure warming mask is indicating a clipped channel (only red for example at 255), but the total luminance of that area is 240 for combined channels.  If I create a mask wall at 240 luminace value and darken everything above that, then I destroy all the whites in the image which also sit around 240.

    I've had a look at the colour selection tool.  Tried the small and thin donut idea thinking it could perhaps isolate whites (or neutrals perhaps?).  Hard to explain what it's actually doing but it's certainly not isolating whites or doing anything predictable, strangely it seems to be affecting light colours the most.

    Tried the colour editor to select coloured highlights, it is definitely not able to differentiate between the clipped areas I'm trying to target and practically everything else.

    Agree with the colour selection tool functionality idea - would be better if it could also select based on luminance, that would be a nice addition.

    In summary, I was not able to use the colour tools to select/isolate the desired clipped highlights.  So far only the exposure warning overlay seems able to understand & isolate which areas I want to target, but there's no way to use that as a selection or within a tool directly, in a way that works for me.

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  • BeO
    Top Commenter

    ...calibrating to a test target is great for calibrating test targets, but unlikely to be helpful to obtain accurate colors for glossy and translucent materials (e.g. paints, metals, and porcelain), non-isotropic materials (e.g. textiles, papyrus, and parchment) or textured surfaces (e.g. art with visible strokes and engravings).

    From https://support.captureone.com/hc/en-us/articles/360002653437 about metamersim. But the whole LAB Readouts section

    https://support.captureone.com/hc/en-us/sections/360000704017-LAB-Readouts

    is interesting to read, for rme, if they are helpful to you I don't know.

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  • Brian Jordan
    Moderator

    I've had a look at the colour selection tool.  Tried the small and thin donut idea thinking it could perhaps isolate whites (or neutrals perhaps?).  Hard to explain what it's actually doing but it's certainly not isolating whites or doing anything predictable, strangely it seems to be affecting light colours the most.

    Tried the colour editor to select coloured highlights, it is definitely not able to differentiate between the clipped areas I'm trying to target and practically everything else.

    No offense intended but I doubt you've had the opportunity to fully understand the 2 color tools mentioned here and how they can be fine tuned to address the issues you present.  With reasonable humility, I'm certain I can precisely target the various areas of concern in the video in, frankly, not a lot of time.  I encourage you to take the opportunity to more fully understand the tools available before dismissing them out-of-hand.

    Capture One is used extensively in cultural heritage applications for art reproduction

    If this were such a grievous issue with no ability to correct blown areas, I doubt this would be the case.

    If it's possible for you to share the image you're working on, I'll happily send you a file back with those areas corrected.  You'll be able to see how the color tools can be manipulated in a way to precisely target color ranges.  (Of course, I'll need the ICC profile, as well.)

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  • john hardiman

    Hi BeO,

    In response to your feedback....

    I have checked multiple proof profiles including ProPhoto.  Blown out areas appear as textureless and show channel values at 255.

    Interesting ideas about making an ICC profile for the curved surface, but for practical purposes it's only worth making a single ICC profile for the flat surface, reducing the exposure in Capture One to recover highlights will achieve much the same thing as attempting to make another ICC profile for the highlights on angled surfaces. 

    "calibrating to a test target is great for calibrating test targets". 

    This can be true, but this is not going to help with my request.  The target surface (gloss/matte/semigloss) should match as closely as possible to the type of painting or artwork being reproduced, even better it should be made of the same materials, but that isn't a practical solution for 99.9% of art reproductions.  Having various standard charts on hand is a practical solution so the best fit can be chosen.  Without any reference chart you will be up the creek without a paddle.

    I think the luminance curve you suggest is a reasonable suggestion, but it does bring me back to one of the original points.  To try and target the coloured highlights with it, it will also dull the textured whites (as they are of similar value), which means some kind of additional selections and masking required.  Also, your curve would bring back the white highlights nicely but have a side effect of flattening the textured whites a little if they aren't also masked separately, and in paintings with large amounts of white texture, the flattening of whites can be obvious.  This points to the solution really requiring masking (as opposed to simple tone mapping).  I believe the highlights tool would have a masking effect behind the scenes to try and retain textures (at least it does in Lightroom), but the highlights tool isn't adaptable to what I'm trying to do. 

    In the past I have often done this step of controlling highlights in Photoshop by blending in another copy of the painting with lower exposure and masking that into the highlight areas.  But that can also have similar challenges as I'm finding here in Capture one when it comes to selecting the right areas.  Ideally I would prefer to do it all in Capture One without having to go into Photoshop and mess with layers and extra process.  I also find it easier to manipulate large files in Capture One.  Some reproductions I've made are pixel shifted 400MP files and those tend to bog Photoshop down on my system, but Capture One handles them nicely.

     

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  • john hardiman

    Hey Brian,

    Happy to share files as I watched the video's you shared and tried the colour tools and wasn't able to achieve what I wanted.  I have a bit of experience with colour tools in other software so should have been able to pick these up quickly, but maybe I'm missing something still... Please also note that I'm looking for a generic solution, in the example I shared I was targeting a yellow colour that was clipped and some whites, other artworks will have highlights with a range of hues, so I'm not trying to target individual colours as such, but the specific areas that are clipped, without affecting other areas.  As soon as unwanted areas are affected by an adjustment, then some form of manual masking is required, my ideal solution from this request would be to have minimal manual adjustments or masking and just some quick method of pulling back the clipped highlights that works, whether that's now or in a future version of Capture One.

    Is there a way to contact you directly on this forum?  I can't share the link to files publicly as the artwork belongs to artists.

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  • Brian Jordan
    Moderator

    Nope.  That's not going to happen.  You'll have to select the various colors that are blown and adjust them individually.  There isn't a smart- or AI-anything that's going to be one and done.

     

    If you want to look me up on Facebook, we can continue via messenger.  TBrianJ (specifically, brian.jordan.372019)  Send me a download link there.  I'm interested to take a look as I do have some other ideas but wouldn't discuss them without trying something first.  Not sure exactly how to explain what I'm thinking without doing it first and it's less likely to work than is direct color manipulation.  If that makes sense.

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  • Walter Rowe
    Moderator
    Top Commenter

    Can you use the white slider on the HDR tool on a fill layer + a luminosity mask restrict the tonal range to the very top end of the highlights?

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  • SFA
    Top Commenter

    John,

    A couple of questions.

    Do you have any preferences set in the Exposure Preferences that might be influencing the results of the differently lit areas. (And have you considered insisting that your clients use watercolours rather than oils?  ;-)

    Have you looked at the possibility that Levels, using separate channels rather than RGB, might help the cause?

    Change the option in the Exposure Preferences and hit the AutoLevels to see what effect it may have.

    In general the Histograms seem to suggest that the colours are not covering much of the lower and upper end of the 0 -255 range. That means that those colours that do get there are rather thinly spread which can make getting results from them a delicate task at best. 

    The new smart AI functionality might be interesting for selection purposes. Used at 100% or maybe even 200% view?

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  • john hardiman

    Hello, been busy so a delayed reply to the above.

    Using white slider with luminosity mask:  Just tested on an image, I'm finding the white slider or highlights doesn't have enough range to fully pull back the coloured highlights I was testing.  Unlike reducing exposure which could - that takes me back to the original issue of being able to easily select the right luminosity range without affecting all the wrong areas.

    Preferences set in Exposure Preferences: Had a poke around but can't find anything in there that influences what I'm doing.

    Using separate channels in levels or curves: Interesting idea, had a little look to try and reduce red highlights with red channel but of course that ends up affecting the overall hue and can't be blended on luminosity mode to retain original colour.  It did appear to partially correct the blown highlight from the red channel but also affects the hue noticeably.  Lets say it did work for a particular area, I'd have to fiddle with different curves for every different colour area in the painting where I want highlights pulled down, so it's not really practical. 

    Exposure preferences and auto levels: Had a look, something I've never tried.  All I ended up doing was blowing out the highlights even more at any settings I tried in preferences.

    Regarding the histogram, I guess you're referring to the picture in a previous comment.  I use a linear response curve for the art reproduction and that tends to push the histogram further left so that could by why it looks like there is less data in the highlights, but in reality the image raw data I make is usually quite carefully controlled and I push the exposure to the right as far as possible without risking clipping.  I make that judgement with colour correction turned off, so it's a controlled environment and probably closer to perfectly exposed than most shooting in the field would be.  Also, if I do underexpose an image more, it doesn't seem to make any difference to this issue of trying to correct the white & coloured highlights in a pleasing and convenient way, so not sure that will lead anywhere. Maybe I'm misinterpreting the idea, not sure.

    AI functionality for selection: I gave that a go a little while back when it first came out and it wasn't even close to working as a way to select/mask the highlights.

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