I never really warmed up to the concept art for the Planet of the Titans Enterprise. Now, I really liked Forbin's model of this concept, but I still wasn't completely in love with it. Then I found this: http://www.galacticempire.org/2011/05/star-trek-planet-of-titans.html More rounded lines, lower neck and nacelles, I can definitely get behind this version. Plus, I can see how this is either inspired by or inspired the TNG Enterprise-D
The progress of that beauty was shown on this very board between 2010 and 2013. http://www.trekbbs.com/showthread.php?t=130992
It looks as different from the concept sketch as the Abramsprise looks different from the TOS Enterprise.
Beautiful, but glad it wasn't the refit. And we thought it took acrobatics to make it make sense as it was...
I love both versions. The painting version should have been done by Ken Adams. His coloration was similar for the Drax station in Moonraker, right down to the interior tubes. The study models had chunkier saucers, which I didn't like. On Ralphs painting, the edge of the saucer is smoother.