On my system I have ImageMagick and its documentation installed:$ apt-cache pkgnames imagemagickimagemagickimagemagick-6.q16imagemagick-dbgimagemagick-docimagemagick-commonI can access convert's man page, which tells me SEE ALSO ImageMagick(1) if I want to know more.man ImageMagick says No manual entry for ImageMagick.And finally, man -k imagemagick says:quantize (5)         - ImageMagick's color reduction algorithm.How do I access ImageMagic's man page on my system?Additional informationAbove I was mistaken.apt-cache pkgnames listed packages are not necessarily available to download, installable or installed (ref. APT-CACHE(8)).So, my command did not list the installed packages.Digging more, I ended up with$ apt list imagemagick*                                                                        Listing... Doneimagemagick/xenial-updates,xenial-security,now 8:6.8.9.9-7ubuntu5.4 amd64 [installed]imagemagick-6.q16/xenial-updates,xenial-security,now 8:6.8.9.9-7ubuntu5.4 amd64 [installed,automatic]imagemagick-common/xenial-updates,xenial-updates,xenial-security,xenial-security,now 8:6.8.9.9-7ubuntu5.4 all [installed,automatic]imagemagick-dbg/xenial-updates,xenial-security 8:6.8.9.9-7ubuntu5.4 amd64imagemagick-doc/xenial-updates,xenial-updates,xenial-security,xenial-security 8:6.8.9.9-7ubuntu5.4 allSo, apparently, imagemagick-doc was not installed.Nevertheless, this package installs the www documentation (/usr/share/doc/imagemagick-doc/www) and not the man one.Checking the content of the imagemagick package does not give away what the name of its man page is, or at least, I am not able to figure it out.$ dpkg -L imagemagick | grep man/usr/share/man/usr/share/man/man1/usr/share/man/man1/stream-im6.1.gz/usr/share/man/man1/display-im6.1.gz/usr/share/man/man1/animate-im6.1.gz/usr/share/man/man1/mogrify-im6.1.gz/usr/share/man/man1/composite-im6.1.gz/usr/share/man/man1/montage-im6.1.gz/usr/share/man/man1/import-im6.1.gz/usr/share/man/man1/identify-im6.1.gz/usr/share/man/man1/conjure-im6.1.gz/usr/share/man/man1/convert-im6.1.gz/usr/share/man/man1/compare-im6.1.gzBug reports hereImageMagick: I've opened a bug report here.Debian: another bug report here.Let's see if someting comes up.
Access ImageMagick's man page
man;imagemagick;documentation