The Process Behind Large Format Scanning

We recently scanned one of the largest items we have ever handled at Townsweb, an extremely large framed artwork from The Royal Edinburgh Military Tattoo.

In this blog, I’ll take you through each stage of the process, from preparing the artwork for scanning, to capturing the scans themselves, and finally the post-processing work involved in stitching multiple scans together to create the final high-resolution image.

How we handle oversized items before scanning

It is so important that we handle this type of material correctly as it is not only extremely large but it is also very delicate and fragile. Two of us helped to manoeuvre the piece from our storeroom to the large format scanner. We did this to protect the material and It was necessary to use two people to handle the item as they had to pick up and move the item through narrow doors and tight gaps. The size also would mean it would be impossible for one person to pick up.

We would usually scan items under the glass of the scanner but for this material we needed to put a stable board onto the glass, this protects the framed piece and makes it easier to move the item for each scan.

Scanning the item

As you can see in this video, we still used two people to handle and move the item for each scan. For items like this, we have to scan multiple images of the item from each area before stitching these scans together to create the final image. This large format scanner works the same as our normal vanguard scanner, except we are able to move the height of the camera with this scanner. We needed to move the camera to the highest point of the stand for this material to limit the amount of separate scans we would need to stitch together.

We scanned this artwork using the highest resolution and scale possible to achieve the best quality. Our digitisation technician, Toby, captured seven separate scans of the material as it was carefully moved along the scanner.

Post-processing

Toby then screen recorded on his PC to show how we stitch together this type of material. To begin with, we open all the scans in Photoshop and check each one to make sure we have captured every detail from the item.

Toby then rotates three of the images so they are all in the same orientation. We rarely have to do this, but with the material being so large, we had to rotate the item halfway through to scan every area. Once all the images are correctly aligned, he selects the Photomerge tool with all the open files selected. Photoshop then automatically merges all the scans together to create one image file. Photoshop can sometimes struggle with this process, and if it fails, we have to merge and stitch the scans together manually.

In this case, the automatic merge was successful. Toby then checks each area of the image to ensure the individual scans have been aligned correctly. Finally, he crops out any unwanted blank areas to create a clean black border around the image.

The final stitched image is now complete!