Display Modes
Working Modes
Tone Ruler
Munsell model

The Colour Watcher Tool

I made the Colour Watcher to help me learn, and use, different Colour Spaces in my post-processing.  The program has grown a bit over the years and is now more like a Swiss Army Knife!

I have added a new feature ...

The Colour Tone Ruler

You can move a superimposed Tone Ruler around the screen.

You can have coloured, or grey scale, zone rulers to help with processing images using the Zone System.

To improve Saturation changes with tones it is possible to define your own swatch tone values or use the Munsell Values and colours (as painters do to create more depth) for the Ruler.

Click here, or on the Tone Ruler button, for further information.

The other features of the program are as follows ...

Colour Spaces and Values

The program samples the pixel under the cursor, even while you are using other programs, and can display one or more of the RGB, HSB, Lab, HEX or Munsell values.  In addition the colour can be display diagrammatically which can be easier to understand and read than the numerical readout.

Here are some examples of how the colour watcher/picker/sampler/dropper can be used...

The basic mode
showing RGB values

A Hue clock with hand pointing to the hue

A Munsell colour picker showing closest match

 Displaying the Lab channel values

Displaying the RGB values as sized circles

Click here, or on the Display Modes button, for further information.

Working Modes

Normally the program will dynamically show the value of the colour as you move your mouse around, but you can also monitor a static point to see how it changes as you alter an image or help with specific changes.

You can fire up as many Watchers as you like and run them in different modes.

There is an inbuilt Magnifier (3 levels) to help with critical positioning and also to give feedback as you set the Shadow and Highlight points.

Click here, or on the Working Modes button, for further information

The Munsell Swatches

Munsell defined a colour model using people rather than technology and the system is (I believe) probably the best way to think when adjust images as it is how we see the colours of the world.

The Munsell colour model can be displayed in different modes, including perceptual out-of-gamut hues if required.

Here is perceptual 5PB.

Click here, or on the Munsell model button, for further information.

Screen Calibration checks

You can use the Watcher to produce a Calibration plot to see how your display responds and changes over time.

It will also show you how the colours change as you move between colour spaces. This is quite a complicated subject/area and if you want to explore it then check out these pages under the Learning from the Masters project.

Just to wet your appetite here are two plots...

The left plot is my reference sRGB one and the one on the right is what happens after the conversion to Lab.

Click here, or on the Calibration button, for further information.


If you wish to use the program, just download it (virus checked by avast), unzip it and place the program on your PC (sorry it will not work on Macs) in a folder and create a short-cut to it.  [Click here to download the older version 3.]

The program is completely free and there is help (maybe worth reading once).

You may also need the Munsell data, download it here by right-click and 'Save Link As', which must be placed in the same folder as the Watcher program, if you want to explore, use or display the Munsell colour space.

Here is the Ruler definition file by right-click and 'Save Link As' for the Zone System (invoked by hitting the '1' key) and it is simple for you to add further definitions - again needs to be in the same folder.