Hmm. So far so good.
I installed QT 5.6.0 open source package which contains all the precompiled binaries from the QT website
I then pointed Cmake to this directory with the command
cmake -DCMAKE_PREFIX_PATH=~/Qt5.6.0/5.6/gcc_64/lib/cmake/ ./
and then installed any missing development libraries which cropped up via synaptic.
However the build of Luminance HDR fails at
[ 46%] Linking CXX executable luminance-hdr-cli
Seeing as I'm not a programmer in any form, I'm loathed to spend much more time on this. A shame that there isn't an appimage available for Luminance HDR.
Perhaps it could be due to the fact that I'm running Linux Mint 18, which is based on Ubuntu 16.04? Perhaps it is "too old" for easy compilation of Luminance HDR? I'm not keen on installing another distro just for one application though...
It'll be interesting to see if any one has any luck with this software...