Creating images of bifolio spreads


A bound codex has to be photographed one folio page at a time. For manuscripts, such as the Venetus A, that are designed and laid out by folio page, these images are sufficient to begin editing. But other manuscripts, such as the Venetus B, are designed and laid out by bifolio spread: the design of the manuscript runs continuously from the verso of one folio onto the facing recto of the following folio. For these manuscripts, it is essential that we be able to cite images illustrating the spread of verso and recto together, as they were intended to be read.


You will need to download appropriate image editing software. These instructions will guide you through using GIMP which you can download here; Mac OS X users may prefer to use the GIMP clone, Seashore: the process is very similar, but some Mac users report fewer problems running out of memory with very large files when they use Seashore.


  1. Your project leader will show you how to consult a list of verso-recto pairs assigned to your team.
  2. Download the two images to combine from the HMT project’s image archive.

Creating the composite image

  1. Open the image of the verso page. (Because the images are so large, you may find it easiest to work with only one at a time.) Check the width of the image. One way to do this is to open from the “Image” menu the “Scale Image..” dialog. (You can cancel the dialog box once you’ve noted the image width.)
  2. Create a new, empty image (File menu, “New…”). Set its width to twice the width of the first image. Set the height to the same height as the verso image.
  3. Select and copy the entire first image (Select menu, “All”, followed by a copy). Because the image is so big, it might take a moment to complete copying. Be patient.
  4. Paste this in to the new empty image as a new layer.
    • In GIMP, choose Select menu, “Paste as…”, “New layer”.
    • In Seashore, Select all, copy and paste. Zoom out so you can see the whole image. Hit “New Layer” on the blue bar that will appear at the top of the screen.
  5. Close the first image, and immediately save the new, large image. Name the file with the MS siglum, verso and recto identifers separated by hyphens (no spaces, please) (e.g., msB-3v-4r.xcf). You should be sure to save the image as a “GIMP XCF image”.
  6. Now open the recto page. Select all and copy.
  7. In your new image, repeat the earlier step to paste the recto into your image as a new layer.
  8. Now comes the fun part: shifting the two layers until they line up reasonably.
    • In GIMP, from the Windows menu, open “Dockable Dialogs/Layers”. In GIMP, you only work in one layer at a time. You can use this dialog to select which layer you’re working in, and to turn off or turn on the visibility of a given layer (by clicking the eyeball to the left of the layer’s thumbnail).
    • In Seashore, (?)
  9. The two images will never sync perfectly. You want to create a composite that makes all the text of each folio side completely visible. The two main things you’ll need to do are:

    slide the position of a layer possibly trim out pieces of one layer’s image if that segment of the image appears in and is better illustrated in the other layer’s image

Proofing and submitting your image


Before submitting your image, check for the following:

Submitting your work

One you are satisfied with your proofed version, please submit your work to your project manager in two copies:

In Seashore, you can draw a rectangle around your final selection, copy the selection, then from the “File” menu, choose “New from pasteboard.” The dialog box will include a drop down menu where you can choose either “GIMP image” .xcf file or “Portable Network Graphics” .png file.