[ferret_users] Setting the limits of the colorbar

[Aisling Dolan <A.M.Dolan08@xxxxxxxxxxx>]

Hi Ferret users, 

I've got a global temperature data set that has + and - temps in it.  I want to compare this with other temperature data sets for publication, but I need the colorbar to be set so it always has the same range (i.e. +20 to -20).  My data ranges from +15 to -18, but I need the colors show on all plots to mean exactly the same temperature. Is there any simple way of setting the colorbar/zaxis to do this?  My data is in the form of a netcdf array, not columns of ascii data.  

Any help would be much appreciated.

Thanks, 
Aisling