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kpolar: regridding to polar co-ordinates

  

This tool allows you to regrid an image using a rectangular to polar transformation. It allows you to see the azimuthal variation of intensity around a given centre. This can be useful for looking at the (optical) structure of galaxies, or doing close inspection of a dirty beam (quite useful when doing radio astronomy).

To use this programme, all you need is an image file, which you load with the Files button. Once your image is loaded, you need to define an ellipse:

Please note: this is an experimental programme that (at present) does this transformation in a simpleminded way. It works by binning the input image in radius and azimuth directions using a set of concentric elliptical annuli. Each annulus has a width of one pixel. Some points that you may wish to consider when using this task are listed below:

Feedback on improvements to this task (including code!) is welcome.


next up previous contents index
Next: 11 Superimposing Images Up: Karma User Manual Previous: koords: interactive co-ordinate fitting

Richard Gooch
Wed Sep 2 12:43:13 EST 1998