You can use the View -> Sync Images plugin to synchronize two or more images, so that when an operation is performed on one image (e.g. change of colormap, contrast/bias, pan, regions, scale, wcs, zoom), it also is performed on the other image(s). First choose the images that should be kept in sync. The choose the operations that you want to sync. Click Sync Repeatedly to keep these images in sync. You can also sync once only by clicking Sync Once.

By default, synchronization is reciprocated: a change in any image causes the others to be synchronized. Synchronization can be configured one direction only by unchecking the reciprocate option. For advanced use, the JS9.SyncImages() and JS9.UnsyncImages() public API calls are available programmatically or from the command line.

This demo displays Chandra, Galex, Spitzer images of the colliding galaxies NGC 2207 and IC 2163, synchronized on regions and zoom operations. The region screen sizes differ because the image scales differ, but their wcs sizes are identical. Move a region around to see updated region stats for all three.

JS9 Demos:

• the basics
• setting the size of the JS9 display
• menubar styles
• web page control
• preloading images into JS9

• multiple instances of JS9
• control multiple displays with one menu
• creating a JS9 instance dynamically
• syncing images in multiple displays

• adding plugins to JS9
• the imexam plugin
• pan and zoom
• overlaying catalogs
• dynamic selection of displays

• image blending
• RGB composite images
• creating new colormaps
• masks and opacity

• remote data analysis
• running tasks when a region changes
• image refresh rate for data acquisition

• displaying different FITS datatypes
• support for large FITS files

• using the all-in-one files