Scanners

Which type of scanner is suitable for a particular project depends on the nature of the original document (type, condition, format etc.) and the scope of the project.

For sensitive documents, the choice of equipment and components should be coordinated with an expert.

The most important scanner types at a glance:

Description, ProsCons
  • Scanning of individual, unbound pages
  • Extremely rapid processing with a high efficiency level (up to approx.. 50 pages/minute), automatic feeder
  • Software enables further processing steps (e.g. conversion into PDF)
  • Simple to operate
  • Cutting-up of the documents
  • Limited scan quality
  • Not suitable for documents that are challenging from a conservational perspective
  • Errors possible in the form of a double page feed
  • Adverse effect on the reader unit through dust particles (can deteriorate over time)
Description, ProsCons
  • Scanning of bound documents
  • Style sheets up to A0 (depending on type of scanner)
  • Book cradle to help position the book optimally
  • Special attachments enable gentle scanning at an opening angle of up to (min.) 90 degrees
  • Simple to operate
  • Simultaneous creation of different derivatives (e.g. JPEG) besides the master file (TIFF)
  • Limited throughput due to manual operation
  • When working without an attachment, the document needs to be open 180 degrees
  • The attachment slows down the scanning process
Description, ProsCons
  • Very high throughput
  • Gentle processing (small opening angle)
  • Only suitable for certain books. Limiting criteria include format or nature of the paper
  • Book covers and fold-outs cannot be scanned with a scanning robot; these need to be processed separately on a reflected light scanner


Treventus ScanRobot

Treventus ScanRobot

Description, ProsCons
Special constructions such as the Grazer Book Table (external link) or the Wolfenbuettel Book Reflector (external link) enable a gentle, non-contact digitization of fragile documents (e.g. manuscripts, early printed books, codices)Complicated individual settings and manual handling result in a low throughput
Description, ProsCons
  • For image documents: photographs, postcards, slides, negatives
  • Suitable for high quality demands
  • Suitable for mass digitization
  • Technical or photographic knowledge necessary
  • camera-specific accessories required

 

Description, ProsCons
  • For negatives in a 35mm or medium format and slides
  • Suitable for mass digitization, batch-based processing
  • Simple to operate
  • sensitive to dust
  • Basic skills in image processing is required
Description, ProsCons
3D camera system (360° object representation): consecutive images of an object in a 360° view (uni- or biaxial). And subsequent assemblage of the images by a 3D viewer
  • Time-consuming, depending on the type of object
  • Quality of the result also depends on the viewer’s technical prerequisites 
Laser technology: creation of a so-called point cloud with central survey points. This point cloud is the starter model for the virtual reconstruction of the object
  • Very complex system, not suitable for mass production
  • Requires specific technical knowhow

Practical example – 3D camera system e-pics.ch

Selecting the right device

A list of the main criteria for selecting a scanner is presented below. Tests with your own material and standardised test images are recommended to verify the quality. These are usually provided by the device manufacturers. Test phases in your own house can also be agreed with good providers.  

Criteria for the assessment of scanners:

  • Image quality: sharpness, colour, resolution, use of ICC profiles
  • Protection of the documents: scanning without glass, harmless light, opening angle
  • Scanning speed in practical use
  • Handling, flexibility (different application possibilities for an optimum workload)
  • Software, output format, possibility for network and storage connection
  • Transportability, ergonomics
  • Spatial conditions: areas, ceiling height
  • Noise emissions
  • References, support, maintenance
  • Costs