Digital Imaging

About

These links and documents contain information about best practices for digital imaging of spirit stored specimens.

Introduction

2D specimen imaging is a valuable addition to augment specimen records. Spirit specimens face some unique imaging challenges because of their wet storage. Use and further development of these best practices is intended to improve quality and efficiency of spirit collection digital imaging.

Value of digital imaging in spirit collections

Quality digital images have a number of values 1 including (but not limited to):

1. improved discovery of specimens
2. improved access to collection material
3. potential research material
4. dissemination to the public

Workflows and guides

Explicit workflows are helpful, particularly for new imaging technicians who might not understand best practices working with spirit stored collections and/or little experience with imaging. Workflows are intended to help all technicians work with quality, efficiency, and with best practices for specimen handling. [[iDigBio DROID3 working group (Developing_Robust Object to Image to Data)2] has developed detailed workflows that can be used to help start or improve an existing wet specimen digital imaging project. Initial task list modules have been developed by this group3] and are currently being revised. Additional guides to image capture and editing of fish specimens are available 4,5,6" Bulletin of the Biological Society of Washington 17.1 (2009): 52-59.</ref>. It should be noted that equipment suggestions change rapidly.

Equipment

There is an wide range of photographic equipment available. Gear, particularly camera bodies, change rapidly. iDigBio has assembled a guide with equipment reccomendations7.

Immersion tanks

Wet specimens are best photographed when immersed in fluid. This serves a dual purpose preventing specimen drying as well as reducing glare on the specimen’s surface that might obscure surface detail. Both horizontal and vertical immersion tanks are used to hold wet specimens for imaging8. =Vertical tank= Vertical tanks resemble typical aquarium tanks but are generally narrow and tall. A plate of glass within the tank is used to gently press and sandwich the specimen against the front glass pane of the aquarium. Vertical tanks require camera mount in front of the tank, such as a tripod. Benefits of vertical tanks are cleaner backgrounds, setup mobility, and lighting flexibility. They are well suited for both in-collection and field use. =Horizontal tank= Horizontal tanks can be useful for specimens that need extensive and delicate manipulations and posing, like uncurling or pinning. Sheet glass is sometimes place on curled fish specimens to hold them posed. Horizontal tanks are usually used in combination with a copy stand. An example can be found on the MCZ Ichthyology website[9].

Contributors

Andrew D. Williston

Links

1. Sullivan, J. P. 2016. The Value of Imaging Specimens in Ichthyology. iDigBio Vertebrate Digitization Workshop, Berkeley, CA, April 4 - 6, 2016
2. https://www.idigbio.org/wiki/index.php/Developing_Robust_Object_to_Image_to_Data_(DROID3)
3. www.idigbio.org/content/workflow-modules-and-task-lists
4. http://silurus.ansp.org/ACSI/corresp/digital_imaging_tips.html
5. https://vimeo.com/61663146
6. Sabaj Pérez, Mark H. "Photographic atlas of fishes of the Guiana Shield." Bulletin of the Biological Society of Washington 17.1 (2009): 52-59.
7.iDigBio 2014. iDigBio Imaging Equipment Recommendations https://www.idigbio.org/wiki/images
/8/86/IDigBioImagingGeneralEquipmentRecommendations1_0.pdf
8. Randall, Z. 2016. Imaging Systems: Light Box vs. Copy Stand vs. Squeeze Tank https://www.idigbio.org/wiki/images/0/00/IDigBio-Berkeley_USE.pdf
9. http://mcz.harvard.edu/Departments/Ichthyology/fish_imaging.html