Color Node Interface

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Nuke’s interface is fairly consistent and its color tools present no real problem to navigate. I shall not cover it in great detail, that is what manuals are for. However, for the purposes of this document the color picker needs a special look.

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The color picker interface

Almost all the sliders that you encounter in Nuke will be in the form below. For the most part its components are self exploratory but they still present some quirks that can confuse the new user:

Interface colorpicker.png

A The Parameter Value
The default of this is usually a single value which is either zero or one. Moving the slider will, in color terms, slide between black through grey to white.
B The value slider
look carefully at the number values on the slider and you will see that they do not progress is a linear fashion. Interesting? For some. To set any slider back to its default Command click on it.
C The color picker
Press this icon and you can grab a color from whatever is in your viewer. It has some key-stroke niceties:
  • Command click in the Viewer window to sample a pixel point within it.
  • Command + Option will sample the color from the image before the current operation. If you don’t do this it will sample live from the viewer window ‘'post adjustment'’. HIGHLIGHTED
  • Shift combined with any combination of these key strokes will draw a marquee round a sample area. This should be your default for sampling as point samples are notoriously unreliable.

Beware: when you have finished with the color picker press it again to disengage it or it will continue to sample.

D Color Sliders
This gives you the color sliders window from which you can pick your color value. These are covered in the Color Sliders section.
E Single value / multiple value toggle
This converts the single value slider to a four box one: RGB and A. If, using the color picker or color sliders, you set an active hue as your value then this will automatically be replaced by a four values readout: R, G, B and Alpha. To change a value place your cursor before the digit you wish to alter and Option drag left or right. This creates a virtual slider which will slides your values up and down. If you prefer real (not virtual) sliders then go the color sliders window via button D. You can also select a numeral and press the up and down arrows to adjust it.

Interface values.png

F Animation Menu
This will bring up the animation menu and sub menu. In Nuke everything is animatable via the Curve Editor.

The color sliders interface

From a UI point of view the color sliders interface is a bit of a dog’s dinner, however it is also surprising powerful as it offers many routes into a single color adjustment.

Interface colorsliders.png

For the most part, its use is self explanatory. The color slider value parameters extend way above the visible range (though they don’t go as far as eleven). Pressing the parameter button marked ‘Dyn’ will make the values in the color sliders dynamically change according to their value (tip: this isn't as useful as it seems). The HSV and RGB sliders are familiar enough to most people, but what do the TMI sliders do? Weeeeelllll: TMI stands for Temperature, Magenta and Intensity. In RGB color adjustment two color operations are frequently made:

  • Adjustment of the R and B channels relative to each other. This effectively means either decreasing the R whilst increasing the B or via versa. This dual operation is wrapped up into one within the T (temperature) parameter value of TMI.
  • Adjustment of the R and B channels relative to the G channel. This effectively means pushing the R and G up whilst pulling the G down or visa versa. This dual operation is wrapped up into one within the M (Magenta) parameter value of TMI.

The I (Intensity) value is a simple multiplier. Of these three sliders the T slider is probably the most useful. Photographers and cinematographers in particular might be drawn to its absolute approach to color temperature.

With all these options at one's disposal it is possible to hop quickly from one color sliding set to another (e.g. TMI to set the warmth then HSL to set the saturation). You will quickly feel very restricted when you are obliged to return to Photoshop’s ‘vanilla style’ color picker.

The color swatches set is a useful place to store any colors that you use. All color swatches in any part of Nuke's interface can be dragged and dropped onto practically anything else resembling a color swatch, even the interface controls at the top of each node.

Beware: by default Nuke will perform its color operation on the RGB and alpha of the image (if it has one) which may inadvertently screw up the alpha of a composite. These channels may selectively be switched off in the channels selector parameters (below).

Interface channels.png