Hi Molly,
         There are portable scanners around designed to scan large art works
for museums etc. I attended this workshop and was very impressed.
http://www.niea.unsw.edu.au/research/projects/luxlab-advanced-analytic-scann
ing
I don't know about commercial operations in the USA but guess there must be
people with similar large scale scanners.

Alternatively a multi-shot Hasselblad camera on a motorised stand, with
proper lighting or flash can be used to take two or four, 200-megapixel
images and produce a large colour-corrected image stitched together in
Photoshop.
I've done this myself with a large wedding veil but never attempted to print
the image. Unlike hi-end scanners the lenses are not strictly designed for
producing images for stitching but the results I got were good.

There are examples of my 200 megapixel shots on Google Cultural Institute to
give you an idea of what the camera can do.
https://www.google.com/culturalinstitute/asset-viewer/the-golden-shield/OwEc
04HRJBbGjQ Make sure you slide the little bar at the bottom of the thumbnail
to zoom in.

Cheers,
Geoff Thompson
Queensland Museum
Australia

-----Original Message-----
From: SciArt-L Discussion List-for Natural Science Illustration-
[mailto:[log in to unmask]] On Behalf Of Molly
Sent: Monday, 17 August 2015 6:03 AM
To: [log in to unmask]
Subject: [SCIART] Large-format scanning for prints

Hello, everyone, I am exploring the feasibility of making prints of my large
-scale charcoal drawings (84"w x 48"h). Can anyone offer insight, or perhaps
recommend a US vendor who offers these services? Many thanks as always,
Molly

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