Subchapters:

Contours

You can do a contour plot of images:

IDL> contour,image,levels=[0,100,200,300,400,500]

IDL> contour,img,levels=[0,100,200,300,400,500],/fill

IDL> add_path,/es
IDL> confill,image,range=[0,500]

The image here is too big and/or noisy for the contour to be very different from the tvim result. We may have to resize or to smooth the image.

        IDL> image2 = congrid(image,50,50)
        IDL> help,image2
              IMAGE2          FLOAT     = Array[50, 50]
        IDL> contour,image2,levels=[0,100,200,300,400,500]

IDL> image3 = smooth(image,10)
IDL> contour,image3,levels=[0,100,200,300,400,500]

The noise here is lower than 0, let's set all the negative values to 0:

IDL> contour,image3 > 0,levels=[0,100,200,300,400,500]
IDL> contour,image3>0<500,nlevels=10

IDL> pos = [0.1,0.1,0.9,0.9]
IDL> tvim,dist(200),/sc,position=pos,/nof
IDL> contour,dist(200),/noer,pos=pos,nlev=15