In an upcoming entry in his production blog, writer/director Frank Miller addresses some concerns that fans have that his upcoming adaptation of Will Eisner 1940′s comic book series The Spirit will be a retread of Miller’s Sin City movie.

After the film’s teaser trailer and outdoor banner were released last month, many people thought its look — black and white with a splash of red, placed against green scene sets — too closely resembled Miller’s co-directing venture with Robert Rodriguez on 2005′s Sin City.

But Miller confirms that The Spirit is actually a full-color movie, and that he hopes to make it into a movie trilogy all its own.

The director also said that with The Spirit movie, he is trying to do what Eisner, his mentor, intended by creating “something new, witty, and exploratory” and that it will not be just like Sin City.

Another change that fans of the Eisner comic book series are concerned with is Miller’s decision to change The Spirit’s traditional blue hat, mask, and jacket to black. Miller explains that the Spirit’s original blue attire was the product of the limitations of pre-digital printing which necessitated everything in black be printed in blue.

Miller assures that in creating The Spirit’s look for the film, tests were run with the blue color, but that “the blue made the Spirit look like an unfortunate guest at a Halloween party.”

Miller’s aforementioned blog posting will be at the film’s official site soon, but for now, SSH has the first look on the upcoming ninth entry.