Kenko Astro LPR Type II filter is designed for photographing of astronomical celestial bodies, stars and constellations.
Kenko Astro LPR Type II cuts off light pollution from artificial lighting of city streets (mercury and sodium gas charging lamps), and transmits only the light spectrum of stellar objects.
The filter does not affect the color balance of the image.
Note: It is recommended for beginners to obtain some basic knowledge in astrophotography about the use of astronomical filters before practical use.
Often, when photographing the night sky with a long exposure the pictures happened to be overexposed or low-contrast. The reason is in camera that receives polluted light from artificial light sources of the cities. Astronomic filters effectively cut off this unnecessary light making image clear and of high-contrast.
Every astronomical filter has its own purpose of use and differs by specifications or light transmittance characteristics.
Beside is a light transmission chart of Kenko Astro LPR Type II filter. Colored vertical lines indicate the points of the spectrum coming from city lighting:
The chart shows that Kenko Astro LPR Type II filter cuts these spectrum of light coming directly from the street lamps.
Kenko Astro LPR Type II adopts precision coating based on Ion Assisted Deposition technology. In order to achieve the desirable coating specification each coating layer is sprayed on the surface of the filter with the help of ion particles creating coherent multilayer surface more durable, more harder comparing with the common coating.
Unlike Type I model Kenko Astro LPR Type II is not changing the color balance, so it is primarily designed for photography.
However, when shooting with wide and standard angle lenses color shift can occur in peripheral areas of the image. For this reason the we recommend using Kenko Astro LPR Type II filter with 100mm telephoto lenses or more (converting to 35mm film).
Below is a sample shot with wide angle lens (24 mm for 35mm full size cameras).
However, if you leave only the central area of the frame, you can see how the filter effectively suppress light pollution.
Kenko Astro LPR Type I features 6 sizes: 1.25" (american size) for eyepiece, 48mm, 52mm, 67mm, 72mm, 77mm to screw on the objective lens of telescopes, SLR cameras and spotting scopes.