Qirab™ Digitisation Column - QDC100

• 1: Qirab™ Manuscript Digitsation Workflow

1 - Qirab™ Manuscript Digitsation Workflow

Introduction

The Qirab™ Manuscript Digitisation Workflow is a standards based digitisation process for achieving high quality color & size accurate images of rare manuscripts for a Preservation Digital Archive which can then be stored and monitored long-term. The purpose of this document is to provide a realistic example procedure for operating a manuscript imaging effort.

The workflow process guides the user through the process of manscript digitisation which includes: system configuration, color calibration, manuscript imaging, quality checks, metadata insertion, image processing, image export, and Preservation Digital Archive creation.

While this workflow was written with Qirab™’s hardware designs in mind (QDC100 & QTC50), any feature equivalent equipment may be substituted.

Requirements

Hardware

Digital Camera & High Quality Lens The digital camera and lens selected have the most impact on the final image quality. Most modern cameras with 40 megapixels or more are suitable for an imaging workflow targeting a 400 ppi image resolution¹. The camera must be supported for tethered operation by the Capture One (C1) software and the lens should have C1 profiles available

Computer capable of running Capture One It is optimal to have a computer which meets the Capture One Recommended system requirements of an Intel 4+ core CPU with 16+ GB RAM, an Solid State Disk (SSD), an NVIDIA or AMD GPU with 8 GB+ RAM, and a Calibrated monitor². The C1 minimum requirements are significantly lower than the recommended.

Qirab™ Digitisation Column (QDC100) The QDC100 provides a stable camera support which is adjustable in 0.5mm height increments.

Qirab™ Conservation Cradle (QCC50) and Tools The QCC50 holds a manuscript safely and flexibly with a suite of attachments to aid in conservation and digitisation.

LED Photography Lights with CRI98+ Color Accuracy LED lights with a high Color Rendering Index (CRI) provide better color fidelity.

Calibrite ColorChecker® Digital SG³ The ColorChecker Digital SG is used to create a ICC color profile for the final exported images. This ensures that different cameras are all producing the same color accurate results.

QP Card gray card⁴ The QP Card is used as an object level target to provide centimeter measurements and standard gray patches to evaluate exposure accuracy and basic color fidelity.

Baxlo Pocket Thickness Gauge Model 2012 (or functional equivalent i.e. Vernier Caliper)

Software

Capture One (C1): Capture One is a high quality digital processing software program. It is used to both operate the camera in a tethered mode and to export the final images with internal metadata. It can be purchased via a subscription model or with a one-time perpetual license

Calibrite ColorChecker Camera Calibration: The Calibrite ColorChecker Camera Calibration program creates an ICC Camera Profile for the camera from an image of a ColorChecker Digital SG color chart. The software is a free download

Qirab™ Metadatatool: The Qirab™ Metadatatool is a free open-source webpage utility to format Dublin Core metadata with an Arabic user interface.

BagIt Python library: The BagIt Python library from the Library of Congress is a command line tool for creation of archival storage folders of digital content. A BagIt folder can be easily validated for file integrity during long-term storage.

OpenDICE: OpenDICE is a MatLab software package for measuring an image’s conformance to the FADGI image quality standard.

Target Standards

FADGI Manuscript Standard: The FADGI Technical Guidelines for Digitizing Cultural Heritage Materials - 3rd Edition (2023) provides specific and practical image quality targets for manuscript imaging.

ICC Camera Color Profile: The use of an International Color Consortium (ICC) color profile insures the best possible color accuracy for the final images.

Dublin Core Metadata: The Dublin Core Metadata standard is a practical way to include manuscript metadata within images in a human readable text format. Qirab created a simple Arabic language Dublin Core Metadatatool for use in formatting metadata for digitisation projects.

NDSA Levels of Digital Preservation: The NDSA Levels of Digital Preservation assist in planning a long-term storage strategy for a Preservation Digital Archive.

Workflow Process

1. System Setup

Setup QDC100 and Lights

• Make sure QDC100 and lights have power connected.
• Adjust LED lights to 5600 kelvin and their maximum brightness.
• Position lights wide to reduce glare off manuscript pages. A 45º angle is a good starting position.
• Use a light meter to check that the exposure is equal in all four corners and center of the imaging area. Adjust the lights to achieve an even illumination as required.

  Important

  Do not move lights once calibration is complete and imaging has commenced

Open Capture One (C1)

• Open Capture One Pro (C1) program.
• Create New C1 Session for each book which is being digitised.
• Name session according to project guidelines. example: 20240131_AAL677.
• Session should be stored in the SSD drive on the computer.

Position Manuscript

• Center Book on QCC50 cradle.
• Push book to back of cradle and then bring forward 1-2 cm.
• Open Live View of Capture One.
• Position book by moving QCC50.
• Adjust camera height to fill image with book.
• Leave space in image frame for the object level calibration target above book. The example uses the QPCard gray card with centimeter marks and a project information card.

Configure C1 Session Guides

The guides will assist with maintaining consistent book position within all images.

• Activate the C1 Guides.
• There should be 1 Vertical and 1 Horitzontal guide centered across the Live View window.
• Reset guides if they are not centered.
• Place ruler on book and measure cover.
• Calculate the center of book cover by dividing height of cover in half.
• Move book with QCC50 to align the center vertical guide with center of book on ruler.
• Create a new Vertical guide if necessary. It will be centered by default.
• Zoom camera with mouse wheel to align precisely.
• Zoom Live View window out to see full camera view after book is centered.
• Create 2 horizontal guides and position them at top of cover and along spine.
• Straighten book to a horizontal guide.
• Create 2 new vertical guides and position them along left & right edges of cover.
• Position guides so that they just touch book.
• Adjust QPCard gray card support to match the height of the cover.
• Moved the support stack to about 1.5 - 2 cm from edge of cover. Use the larger bottom support as handle to move stack gently.
• Position QPCard on the support stacks.

  Warning

  Handle all color reference targets by their by edges only. Do not touch the pigments.
  .
• Create a horizontal guide and position on bottom edge of the object level target card.
• Straighten card to match horizontal guide.
• Zoom in on center guide line and shift card to align with central mark on card.
• Create 2 vertical guides and position of right and left edge of card. This image has an additional info card with its own guideline.
• Create 2 vertical guides and position them on a single centimeter on the object level target.
• Zoom into precisely align the guides to the edges (Right or Left consistently) of the centimeter marks.
• These centimeter guide lines will allow you to adjust height of camera to precisely match the object level target with the page height.

Measure Exposure

• Use handheld light meter or camera light meter.
• Exposure should be something similar to 1/30 sec F11 ISO 100 depending on the light.
• Set exposure in C1 in the Camera tool
  

2. Color Calibration

Photograph Colorcheck SG Chart

• Place Colorbrite Colorchecker Digital SG onto cover.
• Straighten colorchecker top edge to one of the horizontal guides.
• Focus camera with C1 AF button.
• Set Next Capture Name to 0000.
• Take photo or chart.
• Name should be 0000.
• Remove colorchecker and place it in its storage sleeve.

Set White Balance

• In Capture One measure with White Balance tool from QPCard center gray patch or from gray square on ColorChecker.

Export ColorChecker for ICC Profile generation

• Set ICC Profile in Base Characterstics to No Color Correction.
• Set curve to Linear Response.
• Export TIF 16 bit Uncompressed.

Generate ICC Profile

• Import Colorchecker TIF image into Calibrite ColorChecker Camera Calibration application.
• Adjust square grids to match photo.
• Generate the profile.
• Name Profile according to Project requirements (example: 202405 AAL677 NikonD850)

Restart Capture One

• This is required to reload the computer’s ICC profile list.

Set ICC Profile

• Set ICC Profile in Base Characteristics for image 0000 to the newly generated profile.
• Set Curve to Film Standard.
• This setting will be passed down to all subsequent images.

4. Image Recto Sides

Image Cover

• Set next capture naming to 0001A for Recto Cover using the C1 naming token for 4 Digit Counter.
• Insure cover and gray card are aligned with guides.
• Focus camera on cover using C1 Camera Focus tool.
• Take photo of cover.
• Take note of the Start Height of camera on Column Meter.

Open Cover

• Gently secure cover open with Tyvek tool.

Move Camera Down To Page Height

• Measure millimeter thickness of cover board with micrometer.
• Round to nearest 0.5 mm.
• Move camera down the same distance as cover thickness.
• Adjust object level target to page heaight.
• Check gray card height alignment from side view.
• Verify and adjust height of camera by comparing centimeter guide lines with card.

  Information

  Object level target should be aligned with height of text on page. Make a judgment based on curvature of manuscript page.

Setup Guides for Pages

• Create 1 horizontal and 2 vertical guides for page edges.
• Align guides with the edges of the page. The horizontal guide goes along top edge of page.
• They should be contained within the previously created cover guides.
• All imaged pages will be kept inside and aligned with these page guides.
• You can create a guide for the page gutter. But, it will usually not be useful when the gutter is obscured.
• Do not move any guides after this point.

Measure Page Group

• Measure page thickness with Micrometer.

  Warning

  Be careful not to damage pages with tool.
  .
• Based on thickness of a page, calculate how many grouped pages equal 0.5 mm of thickness (ex. 5 page group)
• We will move the camera 0.5 mm after each group of pages is imaged.
• Select this number of plastic counter markers to match group number.

Hold book open with Tyvek/Mylar tool or Acrylic sticks as needed

• The goal is to gently hold the book open without damage.

Image First Recto page

• Focus camera.
• Take image of first page.
• Image name should be 0002A.
• Move one counter.
• Repeat step for recto pages.
• Include blank pages and inner covers during imaging.

Moving Camera Down

• After 1 group of pages, move camera down 0.5 mm.
• Focus Camera.
• Reset counter stack.
• Adjust object level target height to match current page height.
• Zoom in on Centimeter lines on gray card to check the accuracy of the camera height. Adjust camera height as needed to maintain accurate centimeter alignment. Perform this check as often as needed.

Repeat Previous Three Steps for All Recto Pages

5. Image Verso Sides

Reset System for Verso Sides

• Flip book keeping spine direction the same.
• Align book on cradle as before.
• Raise camera to Start Height as noted from before.
• Adjust object level target height to match cover.
• Precisely adjust camera height to get centimeter lines to accurately align with object levbel target lines when Live View zoomed in.

Image Back Cover

• Set Next Capture Naming to 0001B for Verso pages.
  
• Align cover to match guidelines.
• Focus camera.
• Image back cover.

Image First Verso Page

• Open cover and hold with Tyvek tool.
• Move Camera Down the thickness of the back cover board.
• Adjust object level target support height to match page height.
• Align page within page guides.
• Focus camera.
• Image first Verso page (0002B)
• Move one counter.
• Moved camera heigth down for each page group and reset counters.
• Repeat for all verso pages.

Image and Special Details

• If warranted, image Spine and Edges of bound book.
• Image any special details now.
• Image water marks with light sheets.

6. Combine Recto and Verso

Search for all images with A in name

• Used C1 Advanced Search dialog to set Search Criteria.
• Select all A images in C1 browser with Ctrl-A.
• Rotate all selected A images to Left 90º.
• It would be helpful to ceate a search presets for all images with Display Name containing A.
  

Search for all images with B in name

• Select all B images in C1 browser with Ctrl-A keystroke.
• Rotate all selected B images to Right 90º.
• It would be helpful to ceate a search presets for all images with Display Name containing B.

Correct Order of B Images

• Select all B images.
• Reverse Sort order of B pages and Rename Starting with 0001B.
• Undo Reverse Sort of B.
• All pages should now be in order and matched with their facing page.

7. Quality Check

Setup C1 Viewer

• Turn off Guides. They are not applicable to rotated images any longer.
• Reverse Sort All Pages with 0001A at bottom of C1 Browser (for Arabic page order)
• Moving from bottom of C1 Browser list, select first two non-cover pages in Browser (0001B & 0002A). The selected images will be displayed paired in the viewer.

Check all Pages

• Navigate through the selected set (pair) of images using Alt-Left Arrow and Alt-Right Arrow.
• Check for the presence of all pages by comparing paired images to book.
• Look for image quality problems (focus, exposure histogram, page position, object level target position, etc.)
• Re-image or replace any missing or sub-standard images.

8. Crop Images

Crop A Pages

• Set the Crop tool ratio to Unconstrained.
  
• Crop 0001A Cover.
• Select all A with 0001A as Primary.
• Copy & Apply crop from 0001A as Primary to All A images.
• Check all A images for sane crop. Visualize the crop by selecting the C1 Pan tool.

  Information

  Preview the cropped pair by selecting C1 Pan tool. Re-select the crop tool to make adjustments.

Crop B Pages

• Copy 0001A Crop to 0001B.
• Select 0001A & 0001B in C1 Browser.
• Adjust 0001B crop to match realtive page positionwith 0001A in C1 Viewer
• Select All B with 0001B as Primary in Browser.
• Copy & Apply Crop from 0001B Primary to All B.
• Check all B images for sane crop.

9. Metadata

Format Metadata

• Gather all metadata.
• Format metadata in DublinCore format using the Metadatatool from Qirab Github
• Create a Text version. Paste it into a temporary text file.
• Create and XML version. Paste it into a temporary text file.

Add Metadata to Images

• Paste DublinCore Text version into the C1 Description Field of image 0000A.
• Copy & Apply metadata from 0000A as Primary to all images.

Create DC XML File

• Create a new text file named dublincore.xml.
• Paste the XML formatted DublinCore metadata into the new xml text file.
• Save and close the file.

10. Image Export

Configure Export Recipes

• Create Export Recipes according to your project requirements.

Recommeded Export Recipes:

1. TIF (or JEPG200) Archival Master: Uncompressed, 400 ppi, ProPhoto or AdobeRBG ICC profile, 8 bit or 16 bit, and No Sharpening
2. JPG High Quality: Quality Level 75%, 400 ppi, ECIRGBv2 ICC Profile, 8 bit, and Sharpen for Print
3. JPG Reader: Quality Level 55%, 300 ppi, ECIRGBv2 ICC Profile, 8 bit, and Sharpen for Screen

Set Resolution

• Set Next Capture Naming in the Export Settings according to project requirements
• Determine ppi export resolution for each export recipe with centimeter measurement. Adjust export size % to achieve ppi requirement. Target 400 ppi minimum for archival master files⁵.
• Export with Export Recipes

10. Archive Creation

Process JPG Reader images into PDF

• Import the JPG files into a PDF creeator application such as Adobe Acrobat
• Add metadata to PDF settings
• Save PDF from Adobe Acrobat as Reduced Size Optimized

Organize Preservation Digital Object (PDO) folder

• The Preservation Digial Object should contain: tif folder, jpg folder, reader folder, pdf, and dublincore.xml file.
• Rename PDO Folder according to project requirements. example: AAL677_PDO_Folder

Process PDO with BagIT Python script

• Open computers terminal application.
• Add appropriate metadata to BagIt command and process the folder as in this example: python3 /usr/local/bin/bagit.py --source-organization "مجمع اللغة العربية بالقاهرة" --organization-address "https://viaf.org/viaf/150139923" --internal-sender-identifier AAL677 ./AAL677_PDO_Folder
• After BagIt has completed, you should have a folder with your content folders and checksum manifests.
• Run BagIT validation process after: python3 /usr/local/bin/bagit.py --validate ./AAL677_PDO_Folder

Place PDO Folder in Archival Storage

• The archive should be protected in accordance with the NDSA Levels of Digital Preservation guidelines when feasible.
• Set the PDO folder and its contents to Read-Only for long-term safety.
• Move C1 Session with the original raw image files into temp storage for scheduled deletion.

License

The Qirab™ Manuscript Digisation Workflow is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.