# Visualisation

The visualisation of data sets plays an important role in modern astronomy and has been part of our E-Science activities ever since. Usually this is done in close collaboration with the different research groups working on the particular data set. The resulting images and movies are published on the webpage of the respective project. Here we collect additional material and some links.

More videos and images are collected in our Visualisation Gallery. At our E-Science visualisation pages http://escience.aip.de/visualisation you can also find some tutorials on how to visualise your data.

Some hints how to play our stereoscopic 3D movies are given at the bottom of this page.

### Cosmological simulations and galaxy mergers

PMViewer (Arman Khalatyan, available at SourceForge) was used to visualise the distribution of dark matter, gas and stars in cosmological simulations of different projects. Please browse through the corresponding project pages to find some example movies and images (look for "PMViewer" in the movie descriptions):

PMViewer also has a feature for producing stereoscopic 3D movies. A few examples are given here:

• Evolution of the universe
Visualisation of the evolution of the universe in a box with 50 Mpc/h side length until today, with a flight through the box at the end.
Credits: Arman Khalatyan
Box50, mp4, 46 MB, 2D
Box50-stereo, mp4, 96 MB, 3D side-by-side
Box50-agmd, mp4, 46 MB, 3D anaglyph, magenta-green, Dubois
• Merger of Milky Way and Andromeda
This movie shows the gas distribution, centered on the Milky Way. In the upper right corner, the stars are shown from a greater distance, so it's easier to follow Andromeda's approach. The purple ball marks roughly the position of the sun.
Credits: Arman Khalatyan
mw_gas-stereo, mp4, 9 MB  or avi (30 MB),  3D side-by-side
mw_gas-agmd, mp4, 4 MB, 3D anaglyph, magenta-green, Dubois
mw_gas-single, avi, 11 MB, 2D version

### RAVE stars

This 3D movie shows a flight through ~ 380,000 stars from RAVE DR4. Colors encode the radial velocity of each star, from red for > 50 km/s over orange, yellow and cyan to blue for < -50 km/s. This is the same color coding as was used for the RAVE map at the RAVE webpage.

• Flight through RAVE stars
Credits: Kristin Riebe

ravestars-stereo, mp4, 125 MB, 3D side-by-side
ravestars-single, mp4, 63 MB, 2D version

Also see the RAVE movie page for an extended version.
Instructions for creating such movies are available at the E-Science docs.
• RAVE eggshell
RAVE stars distributed on the celestial sphere
Credits: Kristin Riebe

rave-eggshell, mp4, 17 MB, 3D side-by-side

### Miscellaneous movies

• Dark matter halo mass functions
This movie shows mass functions for different time steps for the cosmological simulation MDR1, extracted from the public CosmoSim database.
Credits: Kristin Riebe

massfunctions, mp4, 9 MB, 3D side-by-side
massfunctions-single, mp4, 4 MB, 2D version
• Merging dark matter halos
Positions and sizes of halos that merge from redshift z~5 to z=0 to the most massive halo in the MDR1 simulation. Colors represent the different timesteps; the big red sphere in the center corresponds to the final halo's position and size. The box just helps to guide the eye and has a side length of 40 Mpc/h.
All the information can be extracted directly from the public CosmoSim database.
Credits: Kristin Riebe

mergers-box, mp4, 9 MB, 3D side-by-side
mergers-box-agmd, mp4, 6 MB, 3D anaglyph, magenta-green, Dubois
mergers-box-single, mp4, 4 MB, 2D version
• MUSE cube for Orion nebula (M42)
The MUSE spectrograph produces data cubes, consisting of image slices at different wave lengths. A number of such slices (fitted to characteristic emission lines) is shown in this movie. In the second part of the movie, only those slices are shown which make up the composite images (RGB) in the front. The wavelengths are given in nm.
Credits: Kristin Riebe, Peter Weilbacher, MUSE collaboration

musecube-1280, mp4, 5 MB, 2D version
musecube-fullhd, mp4, 11 MB, 2D version
musecube, justfly, 3D, mp4, 9 MB, 3D side-by-side, just fly around

### How to play stereoscopic 3D movies

Some of our materials are produced for 3D setups, usually by providing a movie file with two separate views: one for the left and the other for the right eye. You'll get the best 3D experience if you have a polarisation 3D TV (or projector) available. Then all you need is a connection to the 3D TV (e.g. via HDMI-cable), polarisation glasses and a movie player that allows you to fix the aspect ratio and play full screen. We recommend using VLC player or Bino for a Mac/Unix distribution or the NVIDIA stereo player for Windows.

If there is no polarisation 3D TV at hand, but you have anaglyph glasses (e.g. green-magenta or red-cyan) available, then you can use a normal screen and a 3D player like Bino, which can convert the side-by-side-movie to anaglyph movies. We provide some movies already pre-converted. If the 3D effect does not look right to you, increase the distance between you and the screen. If front/back objects seem to be mixed, try to switch left and right eye (with the movie player or by just swapping your glasses). In any case, the 3D effect is usually much more enjoyable with the polarisation technique.

• VLC: Start the VLC player and open the movie file. Go to Video -> Aspect ratio, enter the single-image aspect ratio. Usually this will be 16:9 for our most recent movies. Defining this ratio is important to get the correct scale when now switching to View -> Full Screen.
You can also do it all at once from the command line (replace <moviefile> with your file name):
vlc -vvv <moviefile> --full-screen --aspect-ratio=16:9 --loop
Please note that the VLC player won't allow to play two separate movie files, you always need a side-by-side-movie.
In case you have red-cyan anaglyph glasses at hand, you can watch the 3D movie also on a normal screen: In VLC player, select 'Tools' -> 'Effects and Filters', then choose the tab 'Video Effects' and 'Advanced' or 'Miscellaneous'. Now check 'Anaglyph 3D' and check the aspect ratio again to make it look right. If you have differently colored glasses, check the available options e.g. at VLC-Anaglyph
• Bino: Start Bino and open the movie file. Adjust the input and output layout; for our  left-right-movies this means:
Input: Left/right, Output:  Left/right, half width for polarisation 3D TVs.
Bino gives many more output choices. If you have no 3D screen available but anaglyph glasses (e.g. magenta-green) then choose the corresponding output with full color, half, monochrome or Dubois method.