Achromatic lenses are developed to reduce color aberration created whenever white light is refracted, but with even the best designs, color aberration cannot be totally eliminated. Color aberration also consists of a secondary effect called the secondary spectrum. The longer the focal ratio, the fainter the secondary spectrum becomes. Color aberration limits most refractors to a focal ratio of f/15. Reflectors, which is less affected by color aberration, has focal ration of f/5 for commercial design and f/2.5 for professional designs. Within known telescope design, the different conditions necessary for image perfection is integrated, thus forcing engineers to compromise to obtain a close balance that will render the best possible image.

What if magnification, focus, and brightness could be separated? The new formula for aEUR~Miniature Size Telescopes' isolates each of these factors and allow each to be independently tuned for maximum efficiency.

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