Focal Length: Formula & Uses in Optics | Vaia - focal length formula
Neutral densityfilter chart
Neutral densityfilter Ophthalmology
ND filters are also available as grads or graduated ND filters. These filters provide the ND effect on a selected part of the scene. The most common use of a grad filter is to reduce the luminance of a bright sky to match the terrain below.
Neutral density filters explainedfor photography
Dust-Off compressed gas dusters provide potent dust-removing power for you to complete practically any task. Use in your office space to clean keyboards, CPU, laptop or desk area. It is great for removing dust around the home like window blinds, collectibles, sewing machines, holiday ornaments, craft projects and silk flower arrangements. Duster comes with an extension straw to get into hard to reach places. Duster contains a bitterant to help discourage inhalant abuse.
Because the ND effect comes from the coating itself, we’ve gone to great lengths to protect it. On our rectangular filters the coating is sandwiched between two pieces of bonded glass. This protects the coating completely and allows us to lap and polish the filters to the highest tolerance in the industry, meaning your filters will have the lowest possible distortion. On our circular filters, the coating is featured on the outside of the filter because the ring protects the filter. This allows us to add anti reflective and hydrophobic coatings to the outside of our circular filters.