Soft-Proofing Calibration β - the Script for the Perceptual Approach method of making a DN.

Discussion in 'Digital Negatives' started by Dan Pavel, Dec 12, 2017.

  1. Dan Pavel

    Dan Pavel Member

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    After a few months of work the "beta" version of the "Soft-Proofing Calibration" script is finalized and ready for download and testing. The files are here:

    https://drive.google.com/drive/folders/1iTmi6VrmJT8jg3uFB0KRU6JqG-ho3l7O?usp=sharing

    SPC.jpg

    First of all I would like to thank to Mr. Kevin Bjorke, the autor of ChartThrob, for kindly making his script "freeware" and the code of the script public.
    Understanding his code was of a vital importance in my efforts of making this script.


    The "Soft-Proofing Calibration" script doesn't yet include the "Help" files, but it's quite self-explanatory.
    It has 4 functional modules : 1- Make a Chart, 2- Scan and build the Curves, 3- Make the Layer Groups and 4- Make the Print Layer.

    CAUTION
    The results obtained using this script and the "Perceptual Approach" method of making the DN are as good as well calibrated are your scanner and your monitor! But this is the case with all the existent methods of making a DN, so there is nothing new here.
    The script was extensively tested on a Windows 10 machine with a PS6 installed. I don't have PS-CC and don't intend to ever pay for one.
    If the Adobe manual is correct the script should work on MAC and with CC as well, but I have no way to test it. I hope you'll help me to do it.
    The script is, as promised, completely free of charge for all users, for domestic or business applications as well.

    DISCLAIMER
    I have payed very much attention in writing this script. I am makeing it public in a binary file for not permitting anybody to make changes and spread bogus copies.
    No errors appeared while extensively testing it but, as usually, you'll use it on your own risk.

    INSTALLATION
    Just copy the provided "Soft-Proofing" folder and paste it in the "...Program Files\Adobe\Adobe Photoshop\Presets\Scripts\" folder (Photoshop should not be opened during this operation, otherwise it won't let you past anything into its active folders). Next time you'll open Photoshop you'll find the script under the "File -> Scripts" menu.
    The "Soft-Proofing" folder contains the "Soft-Proofing Calibration.JSXBIN" executable file and a hidden "Graphics" folder (you can make it visible if you want) with all the images needed for the UI. The script needs the "Graphics" folder, otherwise it can't run. Don't modify the .png files inside it. The best practice is to let the "Graphics" folder invisible.
    If you want to move the script in other location on your disk move the whole "Soft-Proofing" folder, otherwise it can't find the graphical files in the invisible "Graphics" folder (needed to draw the UI) and it will end in an error.

    1. - MAKE A CHART

    SPC-1.jpg ____ My Chart.jpg

    It actually makes 2 Charts, one with 16 big patches of gray and one with 100 smaller patches and both are later used in the Curves-building module.
    If you are using, like me, more than 1 printer and more similarly-looking transparency films you have the option of imprinting their names on the chart, not to confuse them. Imprinting the exposure time on the chart is almost mandatory and much better than writing it with a pen on one side, as I used to do before. Giving the Chart a name may be useful, as well.
    In the down-left side there is a zone that is practically a simplified bar-code helping the script to identify the type of chart it's scanning. Not very useful in this beta release but I have included this functionality in the hope that I'll find time to offer options for more types of Charts in the future, in the next releases of the script.

    CAUTION : all around the Chart is included a black outline. It is very important to have a dark, thick outline around your printed Chart (I'll explain later why).
    After the script draws the Chart you should use the "Print Layer" module to quickly prepare the negative for printing with your printer. For the best results print it as large as possible using "fit to page" in the printer dialog.

    2. - SCAN AND BUILD THE CURVES

    SPC-2.jpg

    This is the most important and complex module of the script. First you need to scan your Chart printed using your Alternative Process. Then try to crop the scan in such a way that a dark border remains all-around the Chart, with no white zones . The script will use this dark border to make a perfect alignment and to crop the Chart with precision. It should have a width of 10-200 pixels for the best results.
    The following are the functional stages of this module:
    - Evaluates the type of Chart it is scanning based on the scanned image proportions.
    - Evaluates the Charts horizontal/vertical alignment and rotates it to compensate. It can compensate for a max. angle of 2 degrees. That's more than enough for all the real-life situations when your scanned image has an improper horizontal/vertical alignment.
    - After it is aligned the script crops and resizes it to the exact dimensions needed for scan.
    - It verifies the bar-code to check if it is a proper type of Chart.
    - If you chose to ask it to "show patches selection" it will show the regions where it will make the measurements. You can check them and If they are properly aligned it will begin the scanning process.
    - It will scan both Charts and, based on the scanned values, it will build the 2 curves.
    - it will evaluate the dark zones for solarization and the white areas for the paper color and process homogeneity and give you a brief report.
    - If everything works as expected you'll have 2 adjustment layers with the 2 curves on top of the scanned-Chart layer. Save them on the disk in a folder named with the name of your process, toning option and paper (ex.: "Pall_Bergg" for the Palladium on Berrger combination).

    3. - LAYER GROUPS

    SPC-3.jpg

    This module will make for you the layer groups for the best work-flow using the Perceptual Approach. It will turn the PS mode into 16bits/RGB and it will create 3 Layer groups, but only if it detects a "Background" layer with an image for winch you want to make a DN.
    - The top-most is the "Print" group - it will invert and apply your UV blocking color to your image. It should be made invisible until you want to print the DN.
    - The middle group is the group that makes the image on the screen to look like the final print. It contains a Curves and a B&W Adjustment Layers. You'll load in the Curves Layer the curve produced by the script for your intended process/paper combination. You'll keep this group always visible till you want to print the DN and never modify it. For printing the DN you'll have to make the middle group invisible and the top-most group visible.
    - The last group is the working group. You have here a duplicate of your image and another Curves Adjustment Layer where you should load the Basic Adjustment Curve saved together with the Soft-Proofing Curve in the same folder. This is basically a ChartThrob-like curve that will be your initial adjustment.
    On top of the Basic Adjustment Curve Layer you can add as many Adjustments Layers as you need to make the image on the screen look the way you want the final print to be. You can use the whole power of Photoshop to make the image look perfect to your taste ( for instance you can use "Shadows and Highlights" on the copy of your initial image). Local adjustments can be done if necessary, too. Everything is permitted while working in this group. You can even start with a color image(to be able to adjust the sky, grass, etc separately, based on their colors). It will be automatically transformed into B&W in both the upper layers groups (that's why there is a B&W Adjustment Layer included in each of the upper groups).
    While everything is permitted in the Adjustments group NO CHANGES SHOULD BE MADE IN THE "SOFT-PROOFING AND "PRINT" GROUPS. The best practice is to lock them immediately after loading the Curves.
    All the changes you make will let the initial image (the "Background" Layer, made invisible) in the background unchanged, as a reference. It could be used later for other variants of editing/processing.
    The "Printing" group WILL NOT MIRROR YOUR DN. You have to do it yourself (I have this option enabled in the printer dialog). You can chose not to make the "Print" group at all and use the "Print" module instead.

    4. - PRINT LAYER

    SPC-4.jpg

    This module will create a layer containing a DN ready for printing made from the visible layers in your document.
    You can use it to print images created with other scripts, as well. It will not affect at all the layers under it. After printing your DN you could delete the "Print" Layer and make it again whenever is necessary.
    How it works: it creates a copy of the active document in the memory, flattens the copy of the document, applies the "B&W" and the "Invert" Adjustments to it, applies your UV blocking color, mirrors it, flattens the result again, copies the resulted image and pastes it into your document on top of the other layers. It is completely non-destructive and very easy to use.

    Dan Pavel
     
    Last edited: Dec 13, 2017
  2. nmp

    nmp Member

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    Thanks, Dan. Looks wonderful. Just downloaded the files. I am not able to do any chemistry until spring so I can't do a full analysis of the technique until then. I can play it on the computer in the meantime whenever I can. I have CC 2015 on Win10 PC. Will let you know how that works out.

    :Niranjan.
     
    Last edited: Dec 14, 2017
  3. LimeyKeith

    LimeyKeith Subscriber

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    Hi Dan

    Just had time to fire up CC2018, install the files as per your instructions and then run the script - Photoshop crashed with the following image displayed. Is there anything I can check that will help diagnose the problem?

    Screen Shot 2017-12-15 at 08.33.46.png
     
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    Dan Pavel

    Dan Pavel Member

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    Thanks for the report Keith.

    I've checked on Adobe CC2017 javascript issues reports and it seams to be a problem with "iconbuttons" loading their images in scripts in CC2017. They indicate a possible workaround for this issue. I'll make the changes according to their indications and post a CC-friendly version of the script. I'm curios if this issue is with earlier versions of CC, too.

    Another, possibly better, workaround would be to make a variant with a "clasical" interface, with no "iconbuttons" at all.
    I am considering making the separate modules as separate scripts and to launch them into execution by buttons in a group of "Actions" from the main PS interface. It looks like a more convenient way to acces them separately, without a "main" UI.
    Till then, the conclusion is that it doesn't work on CC2017 or latter.
    Sorry for that!
     
    Last edited: Dec 15, 2017
  5. LimeyKeith

    LimeyKeith Subscriber

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    Glad to be of help Dan but I forgot, to mention this was running on a Mac . It runs ok on my Win10/CS6 laptop. By the way, ChartThrob runs ok on the same Mac.
     
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    Dan Pavel

    Dan Pavel Member

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    Yes, that's because ChartThrob doesn't use any "iconbuttons" at all in its' user interface.
     
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    Dan Pavel

    Dan Pavel Member

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  8. ced

    ced Member

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    Dan. thanks for this! Just downloaded the script and in PS CS6 the script built the chart, no problem on Mac so far
    Question, how does the script deal with images coming from cyanotypes or gum where the density is not always very dark to begin with only later after a few coatings does the density achieve it's max.?
     
    Last edited: Dec 17, 2017
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    Dan Pavel

    Dan Pavel Member

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    It should have no problem with lower density processes, like Cyanotypes or single-layer gum.
    I have no experience with multi-layer multi-color gum and Carbon Printing but I think that a different approach and work-flow should be necessary.
    I intend to make some gum-VDB and gum-Palladium printings next spring and I'll see then better what problems appear.

    I've got a ColorMunki Photo recently and made a little script (it's almost finished) that allows the creation of the Soft-Proofing Curve Layer from a palette made with ColorPicker and saved in the ".colors" format. It gives more accurate results than a scanner.
    Would it be helpful to anybody to add the ability of introducing the color data manually, too, as 3 coma-delimited strings of numbers, for instance?
     
  10. ced

    ced Member

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    Dan, thanks for the info! Regarding entering colour data, Yes please, if it is only the 16 fields but if the patches on the right side then that is too much.
    I notice too that the chart is larger tha A5, is it a big deal to make it fit A5 you could if it is needed make the large patches smaller and enlarge the small patches if they are critical for calculations.
    Would be great the option of entering HSB besides RGB for the UV block colour entrance.
    As it is a beta version now is the time to get this info to you.
    Keep up the good work!
     
    Last edited: Dec 18, 2017
  11. nmp

    nmp Member

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    Dan:

    I tried all 4 modules with CC2014 on Win10. Everything worked like a charm! Made up a dummy process output scan to see what is going on with the different modules. I think I understand the methodology. Can't wait to try it on a real process.

    So far so good. I am impressed!

    :Niranjan.
     
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    Dan Pavel

    Dan Pavel Member

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    Thanks Niranjan! It's good to know that it works well on CC2014. Javascript is supposed to work equally on Windows and Mac and my conclusion is that only the changes Adobe made in 2017 are creating problems with loading the UI.

    - I intend to create only 3 fields: R, G and B. In each field 16 coma-separated values should be loaded.
    - To print in A5 or any other format just enable "fit to page" in the printer dialog in Photoshop when you print the Chart. The dimensions of the print/scan are not relevant - they could be as large/small as it's O.K. for you. The script will automatically re-dimension your scan, regardless of it's dimensions, to the dimensions it needs for it's calculations. But, of course, bigger is better...
    - I'll try to implement the option of entering HSB in addition to RGB for the UV blocking color. It shouldn't be too difficult. Thanks for pointing it out.
    I'm also considering to creat a simple ".ini " file that will remember your UV blocking color so that one don't need to introduce it anytime he/she uses the script.

    Indeed, now is the time to know what could be helpful to others and make the changes, if possible.
     
    Last edited: Dec 18, 2017
  13. nmp

    nmp Member

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    I am thinking at some point I will be upgrading to the latest incarnation of CC - have been putting it off for just these types of unknowns. When I do get around to do that, I guess I need to keep this version on my computer. Alternatively is there a way to break up the modules into separate scripts and remove the UI altogether. That way you can invoke each individual module directly from the file>scripts.
     
  14. ced

    ced Member

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    Dan, thank for the info!
     
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    Dan Pavel

    Dan Pavel Member

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    Yes Niranjan, I'm considering removing the main UI and transforming the 4 modules into 4 separate scripts, too. But I think I'll better make them to be invoked from the "Actions" panel, in the main CC interface. I can create an "Actions" group with 4 actions each opening one of the modules. IMO they will be more handy placed this way. There is another reason to make them this way: if I want to latter add a new module I don't have to redesign the whole main UI - I'll only have to place it in the same folder with the other modules. Something like this:

    Actions.jpg
     
    Last edited: Dec 19, 2017
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    Dan Pavel

    Dan Pavel Member

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    Hi Keith,
    I made the changes recommended by Adobe and the CC-friendly script can be downloaded here:
    https://drive.google.com/file/d/1QUxZaTKQlkJj6CsVEQ96ye98C7Az-_D3/view?usp=sharing

    Would you be so king to download it and run it in CC2018 (the same procedure to install it) ? I can't test it myself.
    Thanks!
     
  17. LimeyKeith

    LimeyKeith Subscriber

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    Thanks Dan, I'll check this out for you when I'm home later today. Unfortunately I can't do any of the chemistry stuff at the moment though. :sad: I like the idea of separate modules and it will certainly make things easier for additions/updates as you noted.
     
  18. LimeyKeith

    LimeyKeith Subscriber

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    I've downloaded and installed it again as per your instructions Dan but still get the same problem as before, Photoshop freezes and has to be forced to close. Just to be sure this is where I have placed the download:
    Location.jpg
     
  19. ced

    ced Member

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    Dan I have started messing around with the script and again have some questions.
    At present I am testing it for gum printing and wonder if it is better to scan in 16bit greyscale or 48bit rgb?
    If after scanning and before running the calculation if it is better to slightly blur (gaussian) the scan to get smoother results or are you already doing this in the script?
    It would also be great to have in the 16 patches the % values alongside the 0-255 info if this is not a big deal.
    What purpose does the 2nd curve you save serve other than the curve we need to alter the gradation on the image for the DN? It looks also like an inverted version of the main curve no?
     
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    Dan Pavel

    Dan Pavel Member

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    Keith:
    Thanks Keith, you've been very helpful. The script was properly installed. It looks like the "possible workaround" indicated by Adobe doesn't work. I'll split the script in 4 modules and give-up using "iconbuttons" in the UI.

    ced:
    A'll write a step-by-step work-flow description latter this evening.
    Don't scan in grayscale! It will work but the point of the script is to see your work on the screen in the real-colors of the final print.
    Don't blur the scan - it already does it when counting the medium value of the color in each patch. Blurring could affect the sharpness of the outline of the Chart and this outline is used to align and crop the Chart. However, for low-resolution processes, like gum, it could be helpful to select only the inner part of the scan, living the outlines out, and apply a slightly blur to the selection.
    If you are making a multi-layer/multi-color gum I'm not sure at the moment how the methodology should be adapted. My advice is not to use the script for such a work at this moment.
    If it's a single-layer (black or whatever strong color) gum then it should be OK.

    Have you used ChartThrobe for your gums ? If it worked then this script will probably do the job, too.
    I haven't tested it with gum yet. It is better to start using the new methodology with more homogeneous processes, like VDB, Kallytipe, Salt Print, Palladium, Cyanotype, etc. The gum could be tricky to start with.
     
  21. ced

    ced Member

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    Dan Thanks, I am using single colour gum but multiple passes so it should be okay. I never had good results from ChrtThrb.
    I gaussian blurred 1.5pixels within the white outline.
    Do you do smoothing of the curve after the 1st calibration or don't you bother?
     
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    Dan Pavel

    Dan Pavel Member

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    HOW TO USE THE SCRIPT AND THE "PERCEPTUAL APPROACH" METHOD OF MAKING A DN
    - STEP BY STEP -

    After installing the script as described in the first post open Photoshop and under the "File/Scripts/..." menu you'll see it. Run the script by clicking on "Soft-Proofing Calibration". The script will open (...well, not in CC2017 or latter).

    1. MAKE AND PRINT THE CHART
    • Click "Print a Chart". It will open the "Chart Options" Panel. Fill in the form fields with your printer name, exposure time, etc. and click "Make this Chart". It will build the Chart.​
    • After it does its job click "Print Layer" in the main UI. It will open the "Print Layer Options" Panel. Fill the fields with the RGB values of your UV-blocking color and click "Make the Print Layer". It will add a a layer with a DN of your Chart ready for print (inverted, mirrored and with your UV-blocking color applied).​
    • Print it on your preferred transparency film using the printer settings you use for your DN prints. Take care to include the black outline in the negative! How large/small you print it is not relevant, but bigger is better...​
    • Make a print of the Chart using the process of your choice on the paper of your choice using the exposure time that gave the best results in your previous prints (and imprinted on the Chart). Process it completely, with all the steps you intend to use in your final print, and let it dry completely.​
    2. SCAN THE CHART

    • When the print is dry scan it at 300 DPI in RGB. For the best results your scanner should be well calibrated. Open the scanned image in Photoshop and crop it in such a way that there are no white areas left in the thick black border of the Chart. If the vertical/horizontal alignment is not perfect or the thick black border is not equal on all sides it is not important. The script will compensate the alignment and will crop the Chart with precision.​
    • Run the script again and click the "Scan and Build the Curves" button. It will open the "Scan & Build the Curves Options" Panel. Enable the "Show Patches Selections" option and chose to build both curves. Click "Make the Curves" and let the script do its job. It will rotate and crop the Chart to compensate for the inerent imperfections of the scan and it will show you the outlines of the selections where it will make the measurements. If they are properly aligned click "yes" in the displayed dialog and the script will continue to build the 2 curves. Let it complete its job. In the end it will show a brief report and you will have 2 Curves Layers on top of the Layer with the scanned image of the Chart, Layers named "Initial Adjustment Curve" and "Soft-Proofing Curve". Save the 2 curves with their names on the HD in a folder named with the name of your process, toning option and paper (ex.: "Pall_Bergg" for the Palladium on Berrger combination).​

    3. MAKE THE LAYERS GROUPS

    • Open in Photoshop the image you want to print with your chosen Alternative Process. Run the script again and click "Layer Groups". It will ope the "Layers Options" Panel. Chose to include the "Print" Group and fill the RGB values of your UV-blocking color in the text boxes. Click "Make the Layer Groups" button. The script will create 3 Layer Groups on top of your initial image, Layer Groups named "Adjustments", "Soft-Proofing" and "Print". The Layer Groups are colored different and expanded. The "Print" Group is marked "Invisible" while the other 2 are visible. Close the script and contract the Layer Groups. Make the "Print" Group visible, lock it and make it invisible again. Expand the "Soft-Proofing" Group. It contains 2 Adjustments Layers: "B&W" and "Proofing Curve". Click the Curves Layer named "Proofing Curve" and load in the "Soft-Proofing Curve" you saved in the previous step. Contract the group and lock it. Open the "Adjustments" Group. You have here a duplicate your initial image in a layer named "Image" and a Curves Layer named "Initial Adj Curve". Click the "Initial Adj Curve" and load in the "Initial Adjustment Curve" you have saved in the previous step. It is what its name says: the initial adjustment to be applied to your image, a traditional calibration curve. The traditional approaches in making a DN usually stop here but in this approach this is only the initial stage. Now you are ready to make the DN.​

    4. MAKE ADJUSTMENTS AND PRINT THE DN.

    • Make sure you have the "Print" group locked, contracted and invisible, the "Soft-Proofing" Group locked, contracted and visible and the "Adjustments" Group expanded and visible. The "Adjustments" Group is the working group. You can add here as many adjustment layers you need to make your print look the way you want. While applying different adjustments or filters to the image in this group you will preview on the screen in real time how they will affect your final print, in the real colors of the process you have chosen. Everything is allowed in this group - to add Adjustments Layers, to apply filters to the image saved here, local adjustments, etc. Your Photoshop abilities and your taste are the limits.You can even start with a color image(to be able to adjust the sky, grass, etc separately, based on their colors). It will be automatically transformed into B&W in both the upper Layers Groups (that's why there is a B&W Adjustment Layer included in each of the upper groups). While everything is permitted in the Adjustments Group NO CHANGES SHOULD BE MADE IN THE "SOFT-PROOFING" AND "PRINT" GROUPS. When the image on your (well calibrated) screen looks just as you want your final print to look you can print the DN. Make the "Soft-Proofing" Group invisible and the "Print" Group visible (the "Adjustments" Group should be visible, too). You have now on the screen an image of your DN in the UV-blocking color of your choice. You need to Flip Canvas Horizontal (Image->Image rotation) and print the DN with the same preferences in the printer dialog used to print the Chart. Print the DN using your chosen process and the final print, if your scanner and monitor are proper calibrated, will closely resemble the image you saw on your screen while making the DN.​

    5. THE "PRINT LAYER" MODULE

    • This module will create a layer containing a DN ready for printing made from the visible layers in your document. You can use it to print images created with other scripts, as well. It will not affect at all the layers under it. After printing your DN you can delete the "Print" Layer and make it again whenever it's necessary. It is completely non-destructive and very easy to use.


    HOW TO PLAY WITH THE SCRIPT AND SEE HOW THE PERCEPTUAL APPROACH WORKS
    WITHOUT A WET PRINT


    You can test the script and see how the "Perceptual Approach" in making a DN works without making a wet print. It makes sense to get used to this method before actually applying it to your prints.
    This can be done as described bellow.​
    • Make the Chart as described above. Make the background color in Photoshop Black and rotate the created Chart with a rotation of max. 2 degrees in any direction. Crop the image of the Chart in Photoshop with unequal black borders. This will mimic an imperfectly aligned scan of the Chart.
    • Download this Photoshop Curve file : https://drive.google.com/file/d/1l7cO191vIY_OBQ0KZ535Iovo5ryvmGck/view?usp=sharing It simulates a VDB print on a Fabriano Artistico paper.
    • Apply this Curve to the Chart and then apply "Flatten Image" (Layer->Flatten Image). You have now the dummy image of a Chart processed in VDB on a Fariano Artistico paper.
    • Scan the Chart as indicated and follow all the steps described above. You'll create a DN for a VDB on Fabriano Artistico paper for an image at your choice using the "Perceptual Approach". Play with different Photoshop adjustments and filters in the "Adjustments" Layer Group and see in real time how your final print will respond to this changes.
    PS. : I have replaced the Curve to download for the dummy image of the chart with a better shaped one, for a better mimic of the VDB process. If you have already downloaded the Curve just download it again using the same (updated) link.
     
    Last edited: Dec 21, 2017
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    Dan Pavel

    Dan Pavel Member

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    ced:
    I am not sure how the multi-pass would work with this script. I have limited experience with the gum printing and still a lot to learn.
    You probably should print the Chart using all the multiple passes you intend to use on the final print before scanning it. Otherwise you'll see on the screen the result of just one pass of gum at a time and it will have quite a low contrast.
    You have better experience with the gum printing. Read carefully the step-by-step procedure above and decide for yourself how or if it could be adapted to fulfill your needs.
     
  24. ced

    ced Member

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    Dan, Thanks for the step by step write up, it will be most useful and a lot of info to absorb now and keep me busy. Best regards.
     
  25. LimeyKeith

    LimeyKeith Subscriber

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    And thanks from me too Dan.
     
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