Danny Sanchez Photomicrographer

We wanted to start this post by congratulating Danny on opening his online store.

 The store will sell his prints in one size only, on a specific fine art giclee paper, at a fix low price, to enable anyone to afford his work.

 These prints, however will not be numbered or signed and so will not inherit any additional value but their visual beauty.

http://www.mineralienphotos.com

 

Below is a great article regarding the intricaties of shooting micro photography and gems.

 

Modified Rheinberg Illumination

Nathan Renfro and Danny J. Sanchez

Figure 1. In one method of applying Rheinberg-type illumination, glass slides are fitted to the end of two fiber-optic illuminators and painted with red and blue ink (left) to create a filter that is easily positioned by moving the colored portion of the glass slide into the light path (right). Photos by Danny J. Sanchez. 

Lighting control is one of the most important considerations for maximizing the use of the gemological microscope; with greater control over illumination sources, more information may be gathered from observing a specimen. An interesting technique that gives the microscopist another lighting tool is modified Rheinberg illumination, also known as differential color illumination (M. Pluta, Advanced Light Microscopy: Specialized Methods, Vol. 2, PWN-Polish Scientific Publishers, Warsaw, 1989, pp. 113). This method, as modified for gemological microscopy, employs the use of a contrasting color filter between each illumination source and the subject (figure 1) to achieve an “optical staining” effect (figure 2). When viewing crystallographically aligned subjects such as negative crystals or inclusions with well-defined, reflective crystal faces, each illumination source highlights areas that have the same crystallographic orientation (figure 3). This provides dramatic false-color contrast to an otherwise low-contrast subject. This enhanced contrast makes it easier to observe the relationship between areas in an inclusion scene with identical and also differing crystallographic orientations. 

Figure 2. This silvery metal sulfide inclusion in fluorite shows angular crystal faces, but the low contrast in the image on the left makes it difficult to resolve the orientation of the faces from different sections of the inclusion. Rheinberg illumination provides stark contrast between differently oriented regions by using two colored illumination sources that reflect their independent color off of crystallographically aligned crystal faces, as seen in the center and right images. This allows the microscopist to easily observe the different orientations of the crystal faces in the metal sulfide inclusion, as evidenced by the dramatic boundary of the two contrasting colors. Photomicrographs by Danny J. Sanchez; field of view 1.66 mm. 

Figure 3. With modified Rheinberg illumination to impart contrasting color on some of the crystal faces, the negative crystals in the rock crystal quartz (left) prove to be crystallographically aligned (right). Photomicrographs by Nathan Renfro; field of view 7.34 mm.

We wanted to congratulate Danny on opening his own online store, which will sell his prints in one size on a specific fine art giclee paper, at a fix low price to enable anyone to afford his work.

 These prints, however are not numbered or signed and so will not inherit any additional value but their visual beauty.