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Bessell UBVRI Filters in 50mm Diameter

  • 27500

This item is out of stock but you can place an order now and we’ll ship when it becomes available.


Commonly referred to as the Bessell UBVRI filter set, these filters are primarily intended for photometric measurements of stellar objects using a standard color system. They are 5mm thick,  50mm in diameter and have hard AR broad band coatings on both sides. These filters are also available in 1-inch diameter and mounted for insertion into the popular CFW filter wheel from SBIG. A clear filter to maintain parfocality is also available in both sizes. Gerald Persha, founder of Optec, has written a white paper discussing the subject of filter standards for CCD photometry. In 1990, Dr. M. S. Bessell published a detail description of these filters as used in CCD photometry. Click here to retrieve the original paper.

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