A nine-concentric circle pattern that spans 10 degrees and will reach to the edge of f/ 5.7 optics. Recommended for scopes around this focal ratio or slower. The Laser light is spread over a smaller area, it is brighter than the square grid pattern, this makes it particularly useful with Cassegrain scopes, where the pattern impact is sometimes scrutinized on the mirror surface. The projected pattern is seen only by light that is scattered from dust, dirt, or optical roughness, so a brighter pattern is better, especially if the mirrors are very clean.
Removable diffractive optical element for use in Glatter Holographic Collimators.
Our expert comment:
This is the new version ("NV") with coarse thread. The attachment fits all Howie Glatter/Starlight Instruments laser collimators, which also have a new thread ("NV" in the item number). If you own an older version of the laser (before 2020), please contact us prior to your order!
(Jan Ströher)
