This was something else I've wondered about. I assumed, at first, that the authors had little to no input because so many covers have general Trek imagery. Of course covers like the one for The Face of the Unknown tipped me off that this couldn't always be true.
As I said, cover designs are generally based on the novel outlines, which of course has to be approved before we begin writing the actual manuscripts. So the cover artists
do know what the books are about.
So, does an author have any sort of veto power when it comes to covers? I mean in extreme cases where the artist has included characters that aren't in the book, or drew someone in a way totally inconsistent with how they are described.
Not veto power, no, but we can advise the editor if something doesn't fit or if we think something could be added, and they can change it at their discretion. The Trek editors are pretty good at seeking our input and addressing our concerns. And in a couple of cases, e.g. the last two
Rise of the Federation books and
The Captain's Oath, I've been asked to provide information about specific scenes from the books that the artist thought would be good to depict. But that was their choice to consult me.
I can understand that for promotional material, but I don't understand why in the case of the Graf novels the text that appears on the back of the book couldn't be changed if the books hadn't been printed yet.
I'm not sure, but in those pre-digital days, it may be that the cover art and text had to be locked in earlier than the interior contents. Or maybe it was an oversight.
p.s. Are you happy with the covers of your books? I think, for the most part, Alan Dingman has done a good job designing them for you.
I don't think he's done the actual cover
art on any of my books, except the
Mere Anarchy omnibus -- I think that "cover design" is more like the fonts, colors, layout, etc. and how it fits with the art and text. As for the art itself, naturally it comes out better on some than on others. I like the cover art for
The Captain's Oath, which is by Stephan Martiniere, who also did
The Buried Age. I like the symmetry of that, since they're both books about the untold stories of what
Enterprise captains did in the years before the
Enterprise.