Seymour Solar Telescope Filter (SF425) Fits many different types of equipment: Telescopes, Binoculars, Cameras, and small Refractors. Sun Photography, Solar Events, Sun Pictures, Sun Viewing, Great Teaching Tool. View the Sun with your own eyes through our quality filters. See Sun Spots, and Solar Eclipses. Take pictures of the Sun. Get your solar viewing ready for the Total Solar Eclipse August 21 2017 in the USA.

This is a safe, full aperture, glass solar filter that fits any telescope or binoculars with a tube end diameter between 3 7/8" and 4 1/8". It will specifically fit a Meade ETX 90, Celestron NexStar 80, 80GT, Celestron 90 EQ, Orion ShortTube 80, Observer 70, Astroview 90, Explorer 90; Questar 3.5; and Williams Optics ZS80 II ED. It complies with all safety standards and the light transmittance is reduced to .001%. The full aperture reflective coated glass allows the best possible daytime viewing. This premium solar filter is made with an aluminum cell that is secured to the tube end of the optical device with a nylon thumb screw. The glass aperture is hand selected and inspected. The sun is viewed in a natural yellowish-orange image. Sun spots, granulation, and solar events such as an eclipse, are easily viewed. This filter can be used for direct viewing through the telescope or for photography. The filter is covered in plastic and packaged in a foam lined filter box for protection and shock absorption during handling. It is durable enough to store the filter while not in use. Included are instructions for use and care. How do I determine the size of filter to order? The filter slips over the sky end of your optical tube. You must measure the outside diameter of your optical tube. To measure the diameter use a ruler, tape measurer, or caliper. You want to measure the widest distance across the end of your telescope. Measure from the outside of the casing on one side, across the center, to the outside of the casing on the other side. Order the solar filter size that is just larger than your measurement. You are comparing your measurement with the solar filter inside diameter (ID).