The 10 mm Blocking Filter - BF10 by Coronado:
The Solarmax series filters come in two parts, the front narrowband element (sold separately) and a secondary interference filter which mounts at the eyepiece end of the telescope. You cannot use the individual units separately. If you do not have a SM40, 60, or 90 or a T-Max tuner, it will be more economical to purchase them as a package. Otherwise, choose the secondary blocking filter based on the focal length of your telescope.
As shown in the above collection of Coronado Solar Blocking Filters, the diagonal mounted BF 10 provides full disc images on telescopes with less than 1000 mm of focal length. If you have any questions, please contact OPT, and we will help you put together the correct system for your telescope.
Please Note: Safety is the most important consideration when doing solar observing of any type!
Here are some important considerations if you are putting together a system made from older parts or those of unknown origin:
The president of Coronado Instruments would like to caution people that you cannot swap Coronado blocking filters and narrowband front elements ad hoc without the risk of compromising safety. NEVER pair a blocking filter from an Isle of Man production run (AS1 series filter) with a US-produced SolarMax series filter. The blocking elements have been reconfigured in the newer models and the older blocking filters are NOT compatible from a blocking perspective with the newer front narrowband elements. Coronado can retrofit additional blocking to older blocking filters to make them compatible with newer narrowband elements. They strongly advise anyone considering pairing a front narrowband element with any blocking filter (other than the one it was originally supplied from the factory) to contact customer service at email@example.com to determine if additional blocking is required. Coronado Instruments and OPT will not be held responsible for problems caused by improper matching of filter elements.
OPT Product Number: CI-BF10