Overview
While still shooting 4x5 inch transparency film for
reproduction, for other purposes we now shoot largely digitally,
with the particular aim of making images of our collection
accessible to our staff through the use of our Collection
Management System, (CMS), and to the public through our
website.
For those interested here are some details relating to our
photographic procedures.
Standards
Without wishing to compromise on the quality of our images, we
acknowledge that these images are for practical use in our database
by staff, such as conservators and curators, and for general
viewing by the public. As such they do not constitute replacements
for the original artworks.
With the above in mind, where existing slides were available and
adequate they were scanned for the database even though we may
choose to improve the image quality later.
4x5 inch tranparencies were scanned where available.
4x5 inch transparency film is usually shot with colour
correcting filters to suit the film emulsion batch in use.
Master digital images generally incorporate grey scales or grey
patches, to enable colour interpretation by later users.
Digital images are not retouched to disguise damage to
artworks.
Digital images are shot using the cameras' built in
white-balance features.
Master and derivative images are stored on the Auckland City
Council servers - protected by backup tapes and Business Continuity
Plans.
Documenting the collection is an ongoing process and image
quality and colour accuracy will be upgraded continuously over
time.
As a final goal we would like to be able to produce a saleable
10'x8' print off any of our stored digital files.
Works intended for reproduction in catalogues or to satisfy
reproduction requests from the public are still photographed on 4x5
inch transparency film. (We envisage that this will change as
Colour Management System technology develops universally and easily
applied standards).
Specifications
Slides and transparencies are scanned in house up to a maximum
size of 10"x8" at 300dpi. (Some existing slides have subject matter
in the centre only and produce slightly smaller file sizes with our
slide scanner).
Digital camera images are captured at the highest resolution the
cameras allow.
Master images are filed at full capture size as JPEG files with
good quality/low compression options.
Images of fugitive artworks (e.g. artworks which are changing
visibly in appearance) may be stored as uncompressed TIFF files to
minimise digital image quality loss.
Derivative images for the database are resized to 480 pixels
high or wide - this is an arbitrary size based on a compromise
between good legibility, less than commercial reproduction quality
and ability to be viewed on screen without scrolling.
Sculptures are photographed back and front where possible. Where
practical aproximately 20 VGA images are shot of small sculptures
on a turntable to allow creation of rotateable 3D objects on web
pages. These source images are stored for reuse if technology
changes require it.
Equipment
N.B. This is just a list of some of the equipment we
are using at the time of our digitisation project - it is not
intended to imply that other products, models or brands would be
inappropriate or inferior.
- 4x5 Camera - Sinar camera with a 90mm, 150mm
and 210mm Schneider lenses.
- 35 mm Film Cameras - Nikon F801 bodies with
lenses from 20mm to 200mm including 28mm perspective control lenses
and macro lenses.
- Digital Cameras - Nikon D1X and Nikon Coolpix
5000.
- Slide Scanner - Nikon Coolscan LS-2000 with
SF-200 bulk slide feeder.
- Flatbed Scanner - Microtek Scanmaker 4 for
reflection copy and all transparency formats.
- Studio Flash Lighting - Visatec Solo 1600B
flashes with stands and polarising filters.
- Portable Flash Lighting - a range of Metz and
Sunpak camera and handle mounted flashes.
- Tripods, light stands, easels, reflectors, flash meters, light
meters, colour temperature meter, colour correction filters,
rechargeable batteries.
Software
N.B. This is just a list of some of the software we are
using at the time of our digitising project - it is not intended to
imply that other products or brands would be inappropriate or
inferior.
- Collection Management System - Vernon Systems
Collection.
- Image Editing - Micrografx Picture Publisher
Professional v10, Adobe Photoshop v6.0.
- Departmental Image Management - Thumbsplus
v5.01.
- Immersive Panorama and Rotateable 3D Object
Production - Pixmaker v1.0 Business Edition.
Techniques
There would be little point in trying to replicate the vast
wealth of information available relating to copying and
photographing artworks. Kodak and Agfa amongst others have
publications relating to copying and digital image technology, and
the WWW and any library are of course good sources of
information.
There are however a few techniques we commonly use which are
worth mentioning:
- Standard Copy Setup - two lights and an easel
or copystand.
- Lighting for Surface Texture - raking
light.
- Photographing Through Glass - not shooting the
photographer.
- Minimising Surface Reflection - cross
polarising.
- Minimising Surface Reflection - superimposed
images.
- Sculpture Photography - bounced flash.