| Image capture process | ||||||||||
| Digitising the
collection - photography Auckland Art Gallery Toi o Tāmaki has a long established photographic department and studio equipped with 35mm, medium format, 4x5 and digital photographic equipment as well as studio and portable flash lighting. 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 the Web Browser module of our CMS. 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.
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.
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 copying techniques To view and print the Standard Copying Techniques, which are in Portable Document format (PDF), you will need Adobe Acrobat. This is available for free downloading from the Adobe website. |
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