[Eeglablist] Locating 3d probe positions onto a 2d Projection

[Robert Oostenveld]

Hi Jeffrey

Since you already seem to have clear ideas of the properties of the 
projection of your 3D electrode cloud to a 2D plane, I suggest that you 
have a look at 
http://www.colorado.edu/geography/gcraft/notes/mapproj/mapproj.html. 
Maybe you can find a projection there that suits your needs and that 
minimises that aspect of the distortion that you particularly care 
about (of course each projection distorts).

You can also have a look at the attached matlab function that performs 
some projections of a 3D electrode cloud onto a 2D plane.

best regards,
Robert
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On 1 Dec 2004, at 22:27, Jeffrey Philp wrote:

> Hi Everyone,
>
> As part of a research project I am part of at the University of 
> Auckland in New
> Zealand, I have to transform the 3d positions of the EEG probes on the 
> skull
> onto a 2d projection for visualisation purposes.  I have had a look at 
> several
> spherical and conical projections and they all seem to distort quite 
> heavily at
> quite important locations.  I was wondering if anyone could please 
> reconmend a
> method of projecting these positions that they have found useful.
>
> Many thanks,
> Jeffrey


----------------------------------------------------------------------
Robert Oostenveld, PhD
F.C. Donders Centre for Cognitive Neuroimaging
Radboud University Nijmegen
phone: +31-24-3619695
http://www.ru.nl/fcdonders/
----------------------------------------------------------------------
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