It wasn't until much later that I started to dig into who this "Tim Hildebrandt" was... There is quite a bit of information out there, but here's some descriptive material from the web site of Greg and Tim Hildebrandt:
Welcome to Greg and Tim Hildebrandt's website.My first reaction was "Wow!" I didn't know I had some neat original Hildebrandt artwork!
Greg and Tim Hildebrandt better known to the illustration world as "The Brothers Hildebrandt" began their careers 1959. The Brothers have worked on documentary films and thousands of illustrations for, text books, children's books, calendars, book covers, posters, comic books, advertisements, movie posters, production design for films, collectables and trading card games.
They became internationally known for the original Star Wars movie poster and the 1976, 1977, and 1978 JRR Tolkien Lord of the Rings calendars. Over the last forty-two years Greg Hildebrandt and Tim Hildebrandt have received recognition from their fans in the genres of fantasy, science fiction, comic art, pinup art, western art, religious art, comic strip art, and sequential art. They are deeply grateful for all of their fans.
They have worked for Marvel Comics, DC Comics, almost every book publishing company, Franklin Mint, Batfilms and Lucas Films. They are currently working on the Collectable Card Games (CCG) for Magic the Gathering and Harry Potter published by Wizards of the Coast, as well as several personal projects including a series of 40's - 50's Pinups and a series of tribute paintings that will benefit the families of the fallen firefighters and EMS workers in New York. Many Hildebrandt products have been designated to raise money for the firefighters' 911 disaster relief fund. These can be seen at spiderwebart.com.
Tim Hildebrandt Original Poster Artwork
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From “The Secret of NIMH” (1982). Two items: (1) Original concept by Tim Hildebrandt for the poster and (2) the final poster for the Secret of NIMH -- a Don Bluth film. Concept is signed "Tim Hildebrandt 1982" 2) Final poster -- 2 copies [Unframed Final poster: 27"W x 41"H. Concept in pencil: 13"W x 17-3/4"H] Acquired 1998. SeqID-0344 Updated: 8/15/2005