The new Custom Black

The new Custom Black

The Original
The Custom Black script is designed to generate a Black, Light Black and Gray channel as needed. I had found that in my work I occasionally required just a Black or a Gray channel, and that instead of running the full color separation script it would be nice to have a script tailored just for this. And so was born the Custom Black, as well as it’s partner the Custom White.

The New
Part of the overhaul of the YRGBK script was a refresh of the Black module. While the core approach remains the same, I spent a lot of time looking at how the interface is used, as well as how to improve the techniques and quality of the channels. The result was a much improved Black generator with better options and usability. The Custom Black script uses the same Black module  as the new YRGBK script, with a few additions for generating the channels mid-separation.

The Main Window
The first window in the script provides sliders for controlling how much color masking is applied overall to both the Black and the Gray. Most adjustments for a particular type of color separation or set up can be done with these sliders. Bright images with primary colors and key lines can use a black that is turned way down, while photographic images will work best with the default settings. The slider range is now 0% to 100%, with higher values printing more Black into the colors.

In addition to these sliders, you can open open more advanced dialogs as well as generate a Gray, the Gray Component and a Mask channel from the main window.

The Black generator and the new Saturation Mask Options
In the secondary window for the Black generator I added more options to control how the Mask is generated and applied. This finer tuned control improves both the results of the script as well as its flexibility. With the addition of Tint, Tone and Shadow sliders, the amount of black printing into the colors can be adjusted for different value ranges, while the color sliders allow adjustments for particular colors.

The Saturation Mask revisited
The main component of the Black generator is the mask that limits the amount of black printing into the colors. This is called the Saturation Mask, as it is derived from the color saturation of the image. Starting with the images Luminosity, the mask is applied along with a gain adjustment and color balancing to create a printable black. In the New Black generator I have included more options for adjusting the variables that go into this mask, as well as how the mask itself is applied.

Gray Component remade
In addition to Black, the script can generate a light black I have called the Gray Component.

In a CMYK separation, the lighter grays and the neutral mid values are handled by the Cyan, Magenta and Yellow channels. This  makes for good tonal qualities, but makes a CMYK Black challenging to use for a spot color separation as it tends to be missing these values. The technique used for this is called Gray Component Replacement, or GCR.

 The concept behind the Gray component channel is to generate a channel that prints all these gray values, as well as the values that darken the colors in an image, and to remove these values from the Black channel. This opens the possibility to print the Gray Component as a second Black using a transparent ink, while using a dense Black ink for the key lines. A Custom Black generated with a Gray Component channel will resemble a CMYK black.

While the Custom Black script has always had the Gray Component option, the current version is much more advanced and is optimized for printing. The Black, Gray and Gray Component channels all work together to provide more options for managing the values in a color separation.

Gray Ramp for Gray and Gray Component
In addition to the Saturation Mask, the script also uses a curve adjustment to generate the Gray and Gray component, called the Gray Ramp. The Gray Ramp determines which values go to the Gray channels and which go to the Black.  With the current build for the Gray channels I moved the Gray ramp to a new window just for generating the Gray and Gray Component.

Balancing act
I have also added a function called equalize which balances the black printing over each color. This can be turned off if you prefer to make custom adjustment after the black is generated.

Imagine, implement and calibrate
It is hard to overstate the amount of effort I put into the new custom Black module, but I can say with confidence it was worth it. The new Black module is perhaps the most refined component I have created, and I appreciate this every time I use it. A  Black screen can make or break a print when it gets on  the press, so making sure the Black is perfect may just be the most important part of the color separation process.

For detailed description check out the manual for Custom Black in the tutorials section:

Introducing YRGBK 2.3

Color Separation with YRGBK2.3

the YRGBK main control panel

With a major redesign of the main panel, core advances and fixes, the new version of YRGBK provides easier access to advanced options with improved performance and accuracy.

The redesigned interface puts the most common color separation adjustments in the first window, making the process more intuitive and manageable.

The Black, White and Gray sliders control how far into the colors the values print.  (These are the saturation mask settings from the last version) The values now go from 0 to 100, with higher values increasing the amount of overprint.

The Four color sliders provide control over the Density and Saturation, as well as the amount of color in Shadow and Highlight areas. Checking the Black, White, Color or Gray boxes opens the advanced settings for that option.

The Black generator with the new customized Saturation Mask.
The Black generator with the new customized Saturation Mask.

The Advanced options in the secondary dialogs have been retooled as well, with more control and new adjustments. The new Black Generator offers more control over the Saturation mask as well as custom color sliders to fine tune the adjustment.

The White generator curve and the custom color Mask.
The White generator curve and the custom color Mask.
The Base generator curve and the custom color Mask.
The Base generator curve and the custom color Mask.

The new White scripts provide curve values and custom color adjustments all using convenient sliders.


The Color Generator New Transition Mask manages the mixing between colors for smoother transitions and softer blends. The Midtone adjustment and the Auto Option have been added as well, improving the fidelity of the image and the flexibility of the script.

The color generator and the custom color Mask.
The color generator and the custom color Mask.

Finally, the Gray Ramp is moved to a Gray dialog, which only displays when the Gray or Gray Component are being generated.

The Gray Ramp
The Gray Ramp

Between the main window controls and the advanced options windows, all the major variables in the color separation process can be adjusted. You can read more about it here:

It’s been an exciting process developing a script that offers quality and control up to my highest standards. I am thankful to my many patient and generous supporters and sponsors.

Adjust Colors

Adjusting Colors with the YRGBK script

The Adjust Colors option in the YRGBK script provides a quick way to customize colors in a separation as they are created. In this video I am selecting the Adjust Colors option along with Show dialogs.

For colorful, saturated images screen printed on textiles this is a good approach. Selecting the Show Dialogs option allows access to the Levels as they are applied to each channel. Each color is set to print 100% black in it’s darkest values by sliding the black slider all the way to the first values in the Histogram.

Middle values

In this video I also reduced the saturation value in the script to 5. This compensated for the overall increase in density by shifting the middle, or Gray slider in Levels. I could have also used the Curves option for more control over the middle values. The Curves do not make any adjustments by default.

Customize the White

Customize the White

One of the key features of the color separation script is the Custom White generator. A repeatable white is a big help when designing color separations, and once you get a setting that works for you they rarely need adjustment. The white generator uses both a Curve to adjust the values, and a Saturation Mask to control the overprinting of the Highlight White. In addition there is a set of custom color adjustments which can be used to customize the white channel.

In this video I use the custom adjustments to reduce the amount of highlight printing into the Green and the Yellow. The same adjustments are also available in the Custom White script.

YRGBK as a color mode

The best comparison I can make for the channels generated by the YRGBK script is to look at the color set as a kind of color mode, or color model. Like CMYK, the colors can be printed if you have decent control over the variables. With a few adjustments the color channels can be used to create custom color separations. Looking at YRGBK as a color Mode, which can be printed or used to create custom separations, helps to understand its capabilities and limitations

In this video I am using the script to begin a custom color separation in Adobe Photoshop® CC. I check the Custom black, Gray and the Color Settings options. This generates a gray channel and displays the Black options and the Color Settings preferences.

The color settings handles both the dot gain preview for spot colors, and the dot gain adjustment used in the color conversion.  The dot gain for this print is almost 40%, so I am using the Custom Dot Gain option.

At the end you can see the results of the script. The image used is from the original Photoshop document at 300 ppi, which shows in the quality of the channels.

the YRGBK Options

the YRGBK Options

It’s been a busy week here reorganizing, updating and adding new projects. I still have a way to go, so I hope you will stay tuned. Here is another quick video of the YRGBK Options in action, .

The YRGBK color separator is set up to run using basic default settings. Just click Ok.  For many images this is great, for others the options can be changed. YRGBK has additional option panels for creating custom black, custom whites and adjusting colors. This video shows all three option panels plus the main panel.

With an image like this I could re-run the script and make adjustments to the black setting and adjust the color setting. Often it is possible to merely adjust the channels to balance the image after processing, but in this case there might be some values dropping out. The resulting document contains the original RGB channels, making it easy to repeat the color separation process or run other scripts.


The new Original

I am very excited to share the latest YRGBK color separation script for Adobe Photoshop® CS3 – CC.
Like the original, the YRGBK script converts RGB images into multi-channel images for screen printing.
Check out the video…

It’s been a long year and I have been hard at it developing these color separation concepts, and I think they are ready. The latest YRGBK script goes beyond my expectations, and really stands on its own as a professional color separation tool. I put a lot of work into the black and white generators with tons of improvements. With a new approach to dot gain and a new color system you can really see the difference.

In the video above you can see the YRGBK script run straight through, in real time on a medium sized image, in Adobe Photoshop CC. This particular image shows how well the subtle transitions are handled. In the coming weeks I will post more on the advanced features and how to use them to adjust for different images and substrates.

Read more here

I want to thank everyone for their support and especially for downloading. You make it happen.

Creating a printable color set from the YRGBK script pt 1

(Edit: this post discusses the previous versions of YRGBK.)

The first steps to making a printable color set from the YRGBK color set are to set the black point of each color channel, then adjust for dot gain. In the first, we are making sure that the darkest pixels representing each color are printing at 100%. The second step is to adjust for gain in the printing process.

The concepts apply to custom color separation in general, regardless of how the colors are generated. The YRGBK script merely provides a pretty good head start.

Black point, Dynamic Range, and Ink Coverage
 By setting the darkest value to 100%, we increase the total printable range of each color channel. In addition to increasing the range of values we can represent, setting the black points also ensures good ink coverage in colorful areas of an image. This in turn reduces the amount of pressure needed to get a  good print through a screen, improving both detail and dynamic range on press.

To set the Black point, select a spot color channel
• From the menu choose: Image/Adjustments/Levels
• Move the Black slider to the first set of pixels in the histogram

Dot Gain
With the Black point set, the next step is to adjust for dot gain in the color channel. By applying a curve to reduce the density in the mid range, we can compensate for the gain that occurs on press. A standard adjustment is generally required, although making a custom adjustment for the particular image is best.
(Before making a dot gain adjustment, be sure to set the spot color setting, in the color settings menu, to the correct dot gain for your print setup. This setting modifies the spot color channel preview when more then one color channel is visible.)

To adjust for dot gain:
• Select a spot color channel
• Open Curves from the menu: Image/Adjustment/Curves
• Click on the center (50%) of the diagonal line and move it down to the 30% range.
• This adjustment can be customized to suit the image, spot color, and black point setting.

Setting a custom color
Increasing the value of a channel increases the amount of color printed. The color of a spot color channel should also be considered when setting the pixel density. Using a less saturated, printable ink color compensates for an increase in color density.

• The Use ink colors option in the YRGBK script sets the color channels to printable ink colors.