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by Ted Clarke, USA |
As remarked in the image gallery, Ted has designed and home built a universal student microscope based on a Biolam stand, and is shown in the image below. Notes compiled by the Editor from Ted's e-mails.Some features of the stand: The macro stand, with the LOMO Biolam on the stage, is made from a tool maker's lathe from the early 1900's. The macro stand has an elevating slide under the stage for attachment of a motor drive for a scanning light photomacrography illumination system described in my article "Image Field Size Limitation for Scanning Light Photomacrography" THE MICROSCOPE Vol 41, (1993), 21-30.
The lighting uses a fiber optic light guide and the field lens is an old SLR lens. The condenser with this illumination system is capable of darkfield with the 90X 1.25 NA oil immersion objective. The home-made spider mounted dark-field stops go in a slot at the end of the light guide where the aperture diaphragm is also located.
The light intensity of the fiber optic illumination is controlled by an iris of a pinhole camera system at the illuminator shown in the system image. Thus, color temperature is not affected. Maximum intensity is obtained by fully opening the iris and sliding the light guide in until it is flush with the output end of the illuminator.
The microscope design is discussed in the article: Clarke, T. M. "Building an Affordable Universal Student Microscope"; THE MICROSCOPE 2000, 48, 19-39.
The macro stand was first shown in the author's article "Method for Calculating Relative Apertures for Optimizing Diffraction-Limited Depth of Field in Photomacrography", THE MICROSCOPE, Vol 32:4 (1984) 219-258.
Comments to the author Ted Clarke are welcomed.
