On 7/9/2017 Mike Walter wrote:

> I am looking to gain access to a large flat bed scanner that can scan
> a poster that is 39" wide and 54" tall.  A black and white scanner with
> capabilities to download the image to a computer file is preferred.

In the 1980s and '90s I had many large images reduced, for various
reasons, to standard engineering drawing sizes and 35 mm aperture card
by Tree Towns in Elmhurst, Illinois.  For my work they produced an
8- by 10-inch inter-negative which they could touch up if necessary.
They are still in business and have equipment to do work in the size
you need.  They have a large professional staff that do work for many
engineering, mapping, and graphic arts firms.  Turn-around was always
next day for me, but our office was only ten miles away.

  http://www.treetowns.com/ 

Don Shenbarger