The Huygens Twin Slicer

synchronize views of multiple images, measure distances, plot line profiles

Huygens Twin Slicer is a powerful visualization tool available in Huygens Essential, Huygens Professional and Huygens Localizer. The Twin Slicer allows you to synchronize and inspect views of two or three (different) images. Multiple channels are visible in one view. (Auto)contrast, gamma, and brightness can be quickly set, and different color schemes and LUTs can be selected. With a few simple mouse button clicks, you can measure intensities, sizes, distances, FWHM values, plot line profiles, and more. In Basic Mode (available in freeware mode), image comparison is extremely easy as all viewing settings are applied to both views. By contrast, the Advanced Mode allows you to link (synchronize) or unlink individual viewing parameters. This 'Linking' option facilitates an easy comparison of (the same) image data at different zoom levels, in different colors, as a slice and MIP, or with for example different contrast/brighness setting.

Image Description:
Huygens Twin Slicer window in the Advanced mode showing the raw (left) and deconvolved (right) version of a Widefield image of the kinetochore complex. Automatic contrast was applied to both images. Data courtesy of Dr. Livio Kleij en Martijn Vroomans, Medical Oncology, UMC Utrecht, The Netherlands. Scale bar is one micron.

Twin Slicer Window

Compare images easily

View similar or different images side-by-side using (un)linked viewing parameters.

Optimize contrast, colors & more

Adjust brightness, (auto)contrast, colors, and use LUTs to visualize each channel optimally.

Quick measurements

Perform distance, size, FWHM, and intensity measurements on multiple images with a few mouse clicks.

Visualize and Compare images

The Twin Slicer offers many visualization possibilities. With automatic linking, you can compare two images without any difficulties.

Compare images
Slice through Z and Time
Change orientation
Animate through Z and Time
Different projection modes
Automatic panning
Automatic linking
Data plotter
Change colors
Tune brightness and contrast

Image description:
Widefield image. Data courtesy of Dr. Alexia Ferrand, Imaging Core Facility, Biozentrum, University of Basel

Tuning the Brightness & Contrast

The brightness and contrast controls are accessible in the Contrast panel. The brightness can be changed per channel, or for all channels at once (master).

For more advanced gamma options, click on the Contrast Editor cartoon which opens a new interactive window. Here, you can manually change the image contrast for all channels at once or for each channel individually

The contrast editor can be used to fine-tune the contrast settings in various visualization tools in Huygens, including the twin slicer. It can be found by clicking the little interactive graph under the “Contrast” tab.

Image Description:
MIP renderer in the Twin Slicer showing a Paramecium with adjusted brightness and gamma settings. Image courtesy of A. Aubusson-Fleury CNRS, Gif sur Yvette, Paris.

Change Colors & Look Up Table Editor

In addition to the color schemes that are available in basic mode, the advanced mode allows the use of custom colors. Use the color picker to manually select a color for each channel. For even more refined control, there is the custom look-up table. The Look Up Table (LUT) helps you to make easy intensity comparisons between images, to map image intensities to colors, and to visualize the data in your images as clearly as possible. The LUT editor allows you to load, view and edit your own color schemes to display your images with. In image rendering look-up tables (LUTs) are often used to speed up rendering, and allow for more complex color coding than simply matching higher intensities with brighter colors. The LUT editor can be found by opening any of the slicers or MIP renderers, selecting the “Channels & Colors” tab and setting the Color mode to “Custom look-up table”. A little interactive graph will appear that upon clicking launches the LUT editor.

LUT intensity colors
Emission Colors

Image description:
Image of a maximum intensity projection (MIP) of a z-stack through a Drosophila macrophage imaged on a Leica TCS SP8X scanning confocal microscope. Nuclei are DAPI stained (cyan), alpha-tubulin was detected with a primary mouse DM1A antibody and a secondary anti-mouse antibody coupled to Alexa Fluor 488 (magenta), actin was labelled with phalloidin coupled to Alexa Fluor 568 (green). Image showing emission colors and intensity dependent colors assigned with the LUT editor in the Twin Slicer. Image provided by Eva Wegel, JIC BioImaging, John Innes Centre, Norwich Research Park, Norwich, UK.


Within the Twin Slicer, it is possible to perform the most common basic measurements on the images. For example, you can set a marker to obtain the exact coordinates and intensity values of a certain point in a (ultichannel) image. It is also possible to add a ruler to the image, to determine the distance within a certain part of the image. The slicer will also show the intensity profiles of each channel along the ruler in a separate plot. The Twin Slicer allows plotting of the intensity profiles of all the selected channels of one or of two images at once.

Image description:
Image showing the intensity profile of the displayed two channels along the length of a 2.30µm drawn ruler on the deconvolved image. The plot shows the intensities of both the deconvolved (dashed lines) and raw image (straight lines) that becomes visible again when closing the plot window.