Daystar ERF 150mm with 220mm Cap - E-220N150 Accessories_Adapters Positions: Minimum two

Positions: Minimum two

but pass light in the desired visual spectrum

but it will be reduced to where other techniques such as flatfielding or compositing can make the image acceptable

The filter is optimized for systems with focal ratios between f/0

IPod Touch or IPhone

Daystar ERF 150mm with 220mm Cap - E-220N150 Accessories_Adapters Positions: Minimum two150mm ERF Glass, Cell & 220mm ID Cap For Refractors DayStar Energy Rejection Filters reduce the heat load on your filter assembly by absorbing or reflecting UV and or I light and transmitting light in the desired visual spectrum. These filters are sometimes Red or Yellow glass, or dielectric IR and UV, but pass light in the desired visual spectrum. The ERF can also serve as an aperture mask to accomplish a straight angle of incidence for light