Hue is a foundational concept in image editing and color theory. At its most basic, hue refers to the dominant wavelength or color in light or pigment. Hue is what our eyes perceive as the basic color – red, orange, yellow, green, blue, purple, etc. Understanding hue allows image editors to make precise adjustments to color in digital images.
In Photoshop and other image editing software, hue is a specific parameter you can adjust, along with saturation and brightness, to modify color. Adjusting the hue while holding saturation and brightness constant shifts colors in an image from one hue to another. For example, you could shift yellows to become more orange or greens to become more blue. Hue adjustments are one of the essential tools for color correction and creative color effects in image editing.
What is Hue?
Hue refers to the dominant wavelength of light hitting our eyes. It is our perception of the main color. Scientifically speaking, hue is determined by the wavelength of light. Longer wavelengths are red, with orange, yellow, green, blue, indigo and violet making up the spectrum of visible light.
When dealing with pigment or objects that reflect light, like paints, hue refers to the dominant wavelength reflected. A red object absorbs most of the spectrum and reflects mainly long “red” wavelengths.
Hue is one of the main attributes of color, along with saturation and brightness. Saturation refers to the intensity of a hue, how vivid or muted it is. Brightness indicates how light or dark a color is.
These three attributes of color can be visualized on a cylinder. The hue spectrum wraps around the cylinder. Brightness falls along the vertical axis with black at the bottom and white at the top. Saturation increases from the center to the outer edge of the cylinder.
Hue in Color Models
In digital image editing, hue is a specific parameter you can adjust in color models like HSB, HSL, and HSV:
HSB stands for Hue, Saturation, and Brightness. This model defines a color according to:
– Hue – The basic color such as red, yellow, blue, etc. From 0° to 360° on a color wheel.
– Saturation (S) – The intensity of the color from unsaturated (gray) to fully saturated (vivid)
– Brightness (B) – How light or dark the color is. Ranges from black to the fully saturated hue.
HSL stands for Hue, Saturation and Lightness. It is similar to HSB but with lightness as the third parameter rather than brightness.
– Hue – Same as HSB, from 0° to 360°
– Saturation – Same as HSB, from unsaturated to fully saturated
– Lightness (L) – Ranges from black to white rather than the saturated color.
HSV stands for Hue, Saturation, and Value. Value here is similar to brightness.
– Hue – 0° to 360°
– Saturation – Unsaturated to saturated
– Value (V) – Dark to fully saturated color
While these models have slight technical differences, they all provide hue as an isolated parameter you can adjust to shift colors.
Hue in Photoshop and Lightroom
In Photoshop and Lightroom, you can adjust hue directly with the Hue/Saturation adjustment tools:
| Interface | Controls |
|---|---|
| Photoshop Hue/Saturation | Hue slider shifts all hues together. You can also target specific hue ranges. |
| Lightroom HSL panel | Individual hue sliders for each major color – red, orange, yellow, green, aqua, blue, purple, magenta. |
Adjusting hue allows you to shift colors while maintaining consistent brightness and saturation. Common hue adjustments include:
– Color correcting skin tones and objects that are the wrong hue
– Creative color shifts like making foliage more golden, skies more purplish, etc.
– Converting a color image to black-and-white by shifting all hues together
– Selectively desaturating a narrow hue range to pick out colors you want to emphasize
Hue adjustments are useful in many photo editing workflows from portraits to landscapes to product shots. Mastering hue gives you precise control over the color in your images.
Using Hue in Photo Editing
Here are some tips for effectively using hue adjustments in your photo editing:
– Make subtle hue changes. Shifting hues drastically looks unnatural. Small adjustments often work best.
– Use layer masks and selections to limit adjustments to specific areas rather than global changes.
– Try different Hue/Saturation interfaces. Photoshop gives you more control over specific hues while Lightroom offers an intuitive HSL panel.
– Adjust hue along with saturation and lightness to target color changes. Coordinating all three gives the best results.
– Look for unwanted color casts. Correcting the hue can remove casts from mistakes in camera settings or odd lighting.
– Use hue creatively. Complementary hue shifts can enhance the mood or certain colors in a purposeful way.
– Be careful with skin tone. Even small hue changes to skin can look strange. Use masks and adjust lightly.
– Consider final use. Printed colors may look slightly different than on screen. Preview your edits.
Hue adjustments take some practice to master but give you immense control over color in your images. A strong grasp of hue is invaluable for any photo editor or retoucher working with digital images.
Hue vs. Chroma vs. Color Temperature
It’s easy to mix up terms like hue, chroma, and color temperature when dealing with color in images. Here’s how they differ:
– Hue – The pure color, as distinguished from others in the spectrum
– Chroma – Colorfulness relative to the brightness of a color. Similar to saturation.
– Color Temperature – The warmness or coolness of light, indicated in kelvins. Lower is warmer.
So hue refers specifically to the color itself – blue vs orange vs green. Chroma/saturation indicates how intense or pale a color is. Color temperature shows whether lighting is yellowish warm or bluish cool. All three are important to color perception and adjustment.
Other Color Models
While HSB, HSL, and HSV separate hue as a distinct parameter, other color models take different approaches:
– RGB – Defines a color by its red, green, and blue components from 0 to 255 each. No explicit hue value.
– CMYK – Cyan, magenta, yellow, and black ink model used in printing. Hue is implied by the levels of each ink.
– LAB – Contains a Lightness channel, A channel for green/red, and B channel for blue/yellow. Hue is inferred from A/B.
Many image editing tasks like masking and selections use the RGB model. But HSB/HSL/HSV models allow direct hue manipulation critical for color correction and adjustment.
Measuring Hue
When analyzing and adjusting hue in images, there are a couple ways to measure and quantify hue:
Hue Angle
– Angle around the color wheel, usually 0° to 360°
– 0° is red, 120° is green, 240° is blue
– Photoshop’s Hue/Saturation uses hue angle
Dominant Wavelength
– Wavelength of the dominant frequency of light
– Measured in nanometers (nm)
– Longer wavelengths are reds, shorter are blues
– More precise measurement than hue angle
Hue angle provides an intuitive scale for hue shifts. Dominant wavelength gives a scientific measurement useful for color calibration and conversion.
Color Perception
Human color perception involves more than just the wavelength of light. Other factors influence how we see hue:
– Brightness – Brighter areas appear more saturated
– Surrounding Colors – Adjacent hues influence perceived color
– Object Constancy – We perceive consistent hue across varying light
– Memory Colors – Certain colors have preset representations in our minds
– Optical Illusions – Some patterns alter apparent hues
So hue alone does not fully define the color we see. Visual system quirks can override wavelength input. Image editing apps account for some of these factors when processing hue.
Hue in Logos and Branding
Hue takes on special importance in logos and branding where consistent color is key. Some principles:
– Limit hues – Stick to one or two hues that represent your brand
– Use subjective hue meanings – Blue connotes trustworthiness, green implies nature
– Ensure accessibility – Certain hue combos help colorblind users
– Pick reproducible hues – Hues within CMYK gamut print more accurately
Logo hue selection impacts marketing, reproducibility, accessibility, and legacy. Major brands invest substantial research and testing into nailing down the exact hue for their visual identity.
Cultural Associations
Hue preferences and associations vary across cultures:
| Region | Hue Associations |
|---|---|
| Western Cultures | Red = passion, Green = envy, Blue = sadness |
| East Asian Cultures | Red = luck, happiness; Green = future, youth |
| South Asian Cultures | Red = purity; Yellow = merchants/trading |
Editors working with international content should understand how cultural backgrounds shape hue perception. Target colors and associations appropriately.
History of Hue in Art
The use and understanding of hue evolved in art history:
– Prehistoric – Mainly earth pigments: reds, browns, blacks
– Ancient Egypt – First synthetic pigments and glazes
– Middle Ages – Pigment production expands greatly in Asia and Europe
– Renaissance – Optical color mixing, landscapes with broad hue palettes
– Impressionism – Interest in optical hue effects like complementary colors
– Modern Art – Fauvists, abstractionists, op artists explore new hue uses
– Digital Age – Photography and image editing bring hue adjustment to the mainstream
Modern photo editors have an immense hue palette at their fingertips thanks to the legacy of hue innovations across art history.
Teaching Color and Hue
Some methods for teaching hue and color relationships:
– Color wheel – Arrange hues in a circular format to show relationships
– Color mixing – Combine paints, lights, or filters to demonstrate hue derivation
– Contrasting images – Compare photos side-by-side to isolate hue differences
– Gradient examples – Show hue transition in smooth steps for blend effects
– Color naming exercises – Have students identify and name a variety of hue samples
– Reproduction challenges – Test ability to pick suitable hues to match a reference image
Hands-on color exercises boost students’ intuitions and vocabulary for thinking about and discerning hue.
Conclusion
Hue is a core foundation of image editing and color theory. It refers to the dominant color we perceive due to the wavelength of light. In image editing software, hue is a parameter you can adjust to shift colors while maintaining brightness and saturation. Hue controls allow for precise color changes for correction and creative effects. Mastering hue as part of the HSB/HSV color models is a fundamental skill for photography and design professionals. Hue may seem simple on the surface, but has nuanced technical and perceptual complexity. With practice, hue adjustments will become a versatile arrow in your retouching and editing quiver. Keep hue in mind as you tweak colors to get images looking their vivid best.
