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Gulf Coast Repository

PICAT Thin Section Viewer

Overview

Thumbnail image of PICAT Thin Section Viewer The PICAT (Petrographic Image Capture and Archival Tool) provides an easy and versatile imaging process that captures a publication-quality image (the equivalent of 300 DPI on an 8-1/2 x 11 inch page) of an entire thin section slide in plain, polarized and cross polarized light.

Instrument Make and Model

Custom-built system.

Estimated Measurement Time

  • Image Collection: 2–3 mins/image

Principles & Analytical Capabilities

The PICAT is composed of a Kaiser camera stand and photo table with a System-V RGB light source with OSRAM HLX 12V 100W Bulb at the base. A stationary stage has two slide holder options and is bracketed by a set of two rotating 95 mm diameter polarizing glass filter elements. The user can move the two filters in and out of the light path independently. The filters can be rotated as needed to optimize the polarizing light for an image.

The camera for this system is a Canon 5D Mark II with video capability. The sensor is a CMOS full-frame sensor with a resolution of 21 megapixels. The camera produces "Live View" images that can be displayed on a tethered computer system. The system is also capable of 1920 x 1080 video. The camera is powered by an AC adaptor. The camera colorspace is SRGB.

The standard set-up of the camera uses a Cannon EP 100 mm IS Macro Lens to take an image of an entire thin section. A Canon MP-E 65 mm 1x–5x Macro Lens can be used to take advantage of the zoom capability.

Data Generated

Image Files

  • JPG: image of thin section in polarized or cross polarized light that has been compressed from the raw file, approximately 6MB filesize
  • RAW (raw): raw image of thin section in polarized or cross polarized light, approximately 30MB filesize

Data Example

Thin section images in polarized (left) and cross polarized (right) light from Hole U1654F.
Thin section images in polarized (left) and cross polarized (right) light from Hole U1654F of IODP Expedition 395 in the North Atlantic Ocean on the eastern flank of Reykjanes Ridge.1

Procedures & Manuals

References

1  Parnell-Turner, R. E., Briais, A., LeVay, L. J., Cui, Y., Di Chiara, A., Dodd, J. P., Dunkley Jones, T., Dwyer, D., Eason, D. E., Friedman, S. A., Hemming, S. R., Hochmuth, K., Ibrahim, H., Jasper, C., Karatsolis, B. T., Lee, S., LeBlanc, D. E., Lindsay, M. R., McNamara, D. D., … Tian, C. Y. (2025). IODP Expedition 395 Thin section images [Data set]. International Ocean Discovery Program. https://doi.org/10.5281/zenodo.15054684