Important Notice: Our web hosting provider recently started charging us for additional visits, which was unexpected. In response, we're seeking donations. Depending on the situation, we may explore different monetization options for our Community and Expert Contributors. It's crucial to provide more returns for their expertise and offer more Expert Validated Answers or AI Validated Answers. Learn more about our hosting issue here.

What does it mean that a solar filter is coated to density four, or density five?

April 26, 2017Coated density filter mean solar

0

Posted

What does it mean that a solar filter is coated to density four, or density five?

1 Answer

0

Posted

Pre-telescopic filters are described by their density, their transmission, and their extinction in astronomical magnitudes. Transmission is simply the proportion of transmitted to incoming light and is usually expressed as a percentage.