[magick-users] Converting jpg to monochrome results on blank picture

[Alberto Simões]

Hi.

I am doing some experiments with images, and I am converting some test
images to a monochrome thumbnail.
I am using a convert line like this:

  convert foo.jpg -resize 150x150 -monochrome out.jpg

If you want to check the picture I am using check this image:
http://eremita.di.uminho.pt/~ambs/_/O/ShannonStewart.jpg

and the converted image:
http://eremita.di.uminho.pt/~ambs/_/MT/ShannonStewart.jpg

What I might be doing wrong?
Thank you

Ablerto

-- 
Alberto Simões