Fungi are employed to produce industrially important glucoamylases. Most glucoamylases are glycosylated. Glycosylation enhances the enzyme stability. Glucoamylases contain both starch binding and catalytic binding domains, the former being responsible for activity on raw (insoluble) starch. Proteases may act on this domain causing the enzyme to lose its activity on insoluble starch. Optimal activity is observed at pH 4.5 to 6.5 and 50 to 70 degrees C. Glucoamylases contain up to 7 sub-sites with highly varying affinity. They can be produced by different methods including submerged, solid state and semi-solid state fermentation processes.

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The pinhole camera may often be overlooked because of its apparent simplicity. However, it is a useful and practical device which offers freedom from distortion and virtually infinite depth of field. Its astigmatism can be corrected by proper choice of aperture, and its angular field can be made to exceed 90 degrees . With modern light sources, films, and detectors, even the pinhole's low aperture need not be an important limitation.