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Infrared image analysis

Adjusting the temperature range, choosing color palettes, and setting alarms

Adjusting the displayed temperature range

Use the temperature slider at the bottom of the screen to adjust the contrast of the infrared image.

  • Drag the blue handle and red handle to set the range
  • Drag between the two handles to slide the whole range
  • A histogram (temperature distribution) is shown in the background

Quick adjustment with the Shift key

You do not have to reach for the temperature slider — hold Shift and move the mouse over the image to adjust the display range (no clicking required). Dial in the contrast quickly while keeping your eyes on the image.

ActionEffect
Hold Shift and move left/rightSlide the display range
Hold Shift and move up/down, or use the mouse wheelWiden or narrow the temperature span (contrast adjustment, center preserved)

Release Shift to finish. This works in the main viewer, the ortho viewer, and the 3D view.

Percentile presets

Double-click the temperature slider or click a preset button to jump to a commonly used display range.

PresetDescription
95%Standard range excluding outliers. Higher contrast (default)
98%Slightly wider range. Use when extreme highs and lows should also be visible
100%Full data range. Lower contrast because outliers are included

Locking the display range

You can lock the display range from the right-click menu. While locked, the range is preserved when switching images. Unlock by double-clicking or via the right-click menu.

Alarm settings

Use the alarm bar on the right side of the viewer to set temperature alarm thresholds.

  • Drag the red handle (upper limit) and blue handle (lower limit) to set the thresholds
  • Drag between the two handles to shift both thresholds together
  • Pixels inside the threshold range are colored with the palette; pixels outside are shown in gray
  • Double-click to reset the alarm thresholds

Locking the thresholds

You can lock the thresholds from the right-click menu. While locked, the thresholds are preserved when switching images. Unlock by double-clicking or via the right-click menu.

The temperature slider state and alarm settings are saved automatically.

Temperature mask

Masks pixels outside a specified temperature range and excludes them from statistics. You get accurate maximum, minimum, and average temperatures that are not skewed by sky or background in the frame.

Infrared image with a temperature mask applied

How to configure

Open the settings from either of the following:

  • The button to the right of Infrared Image in the display mode bar (tooltip: Temperature Mask Settings)
  • Settings ▾Common Settings...Temperature Mask tab on the toolbar
ItemDescriptionDefault
Enable Temperature MaskTurns the mask on or offOff
Lower LimitMasks temperatures below this value (-100.0 to 100.0 °C)-20.0 °C
Upper LimitMasks temperatures above this value (100.0 to 3000.0 °C)1600.0 °C
Display masked areas using the visible imageWhen on, masked areas show the visible image; when off, they are shown in grayOff

Preset buttons apply representative values quickly.

PresetLower / Upper
Default-20.0 °C / 1600.0 °C
Strict-10.0 °C / 500.0 °C
Lenient-40.0 °C / 2000.0 °C

Where it applies

The settings apply to both the main viewer and the ortho viewer, and measurement statistics are recalculated. They are also reflected in report output and image export. The settings are saved with the project and restored the next time it is opened.

The operating range of the temperature slider (display range) is not affected by the temperature mask. Even with a mask configured, you can adjust contrast across the image's full temperature range.

Color palettes

Choose how infrared images are colored from 10 palettes.

Standard palettes

PaletteCharacteristicsRecommended use
IronbowExpresses temperature differences with both brightness and hueGeneral purpose. The most widely used standard palette
RainbowWide gamut that color-codes temperature bandsOverview of temperature distribution
Rainbow HCHigh-contrast variant of Rainbow with more colorsDetecting subtle temperature differences, detailed analysis

Scientific palettes

PaletteCharacteristicsRecommended use
InfernoPerceptually uniform color transitions; color-vision friendlyQuantitative analysis, reports
HotIntuitive representation of "heat"Locating heat sources, finding insulation defects
LavaWarm palette with rich gradation in dark areasAnalyzing hot spots, visualizing temperature gradients
CoolwarmSymmetric scheme with white at mid-range temperaturesDeviation from a reference temperature, hot/cold comparison
ArcticCool-toned palette with a chilly lookLow-temperature analysis, condensation and air-leak surveys

Monochrome palettes

PaletteCharacteristicsRecommended use
White HotCold is black, hot is whiteTraditional display mode
Black HotInverted grayscale — hotter is darkerTraditional display mode

Edge display

Open the edge panel from on the toolbar. Two features are available: temperature edges and contour enhancement.

Temperature edges

Visualizes the boundaries of temperature changes, making areas with steep temperature gradients easy to spot.

SettingDescription
SourceExtract edges from the display (image after colormap) or from temperature (temperature data)
Reference ImageChoose the infrared or visible image as the reference
SensitivityEdge detection sensitivity (0–100)
OpacityOpacity of the background image while edges are shown (0–100%)

Contour enhancement

Overlays contour lines from the visible image onto the infrared image, so building structure and component boundaries are visible on the infrared image.

SettingDescription
SensitivityContour detection sensitivity (0–100)
Edge ColorWhite or black

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