19 October 2013

Halite casts from Tonoloway Formation under the GIGAmacro lens

Posted by Callan Bentley

The work of team M.A.G.I.C. continues. This is a lovely sample quartet of salt cast samples from Silurian-aged Tonoloway Formation limestone. I collected these samples on Corridor H’s newly-opened section west of Moorefield, West Virginia, last spring. The big one at the bottom was collected by my friend Leigh Henry, who graciously loaned it to M.A.G.I.C. for imaging purposes.


This GigaPan turned out well in some regards, and poorly in others. The lighting, I think, is just about perfect. The size and resolution are awesome (almost 4 billion pixels). However, the most obvious flaw is that the samples are not imaged in totality – the top and left sides of the GigaPan got clipped off. We don’t understand why, and it frustrates us. Making an image like this one is pretty much a four-day-long affair. When something as basic as the edges of the imaged area ends up askew, it’s maddening. Furthermore, the scale bar that we always put in these images somehow didn’t get photographed… I can compensate for that by typing “Width of field of view is 27 centimeters,” but the text isn’t as intuitive as simply having a scale bar there. Argh. Furthermore, what’s not apparent as we set up the shot becomes apparent when you explore the GigaPan image: little chunks of foreign sediment or hairs, dust particles, etc. on the surface of the specimens. It seems that no matter how much attention we pay to preparing and cleaning the specimens (we blast them with compressed air before a shoot), we always miss some of this offending “litter”.

The samples were collected at this roadcut: