User manual

selected planes, Aladin will use them to fill the form, else Aladin will take the 3 images
on top of the stack, or else the 2 first ones. If the image associated wavelengths are
known, Aladin will sort them according to this parameter
Specific case for 2 images
It is possible to only select 2 images. In such a case, the 3
rd
colour
component will be computed according to the 2 other by taking
the average of the two other images. This method builds very nice
colour images if the free component is the green colour (default
mode).
2 images differences
With 2 images, it is also possible to do a coloured subtraction.
The positive differences will be the values from the first colour
component; the negative differences will be those for the
second colour component. Furthermore, the differences will
be normalized between 0 and 255 to give a maximum
contrast. This method is interesting to visualise variations in a
quick way, even small ones, between two images.
5.10 Images associations: cubes and mosaics
Icon: assoc
Menu: Image => Mosaic image builder…
Image => Blink/Movie generator…
Aladin can associate 2 or more images by combining them either as a cube that will be
displayed as an animated sequence, or by creating a new mosaic image from the original
images.
Access to the association window
The window can be opened either with the menu “Image
=> Mosaic image builder” or “Image => Blink/Movie
generator”, or else with the “assoc” button, and lets you
control the association. You can indicate the original
image planes, the initial sequence delay in the case of
producing a cube, and the reference image if resampling
is needed pour superimposed pixels.
Mosaic
When producing a mosaic image, the image obtained will
have the required size in order to contain all the original
images in the projection grid from the reference image.
The image obtained will be displayed and can be
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