Adjust the brightness level of the Moon, Venus, and other bright objects with the Optolong Variable Polarizer. A standard Moon Filter is similar to a pair of sunglasses. They work fine, but sometimes the scene is too dark or too bright, and there’s not a lot you can do about it. A variable polarizing filter is much more flexible than a Moon filter. It allows you to set the percentage of attenuation by turning the top section of the two-piece filter. Simply attach the 2" threaded filter to a like-sized eyepiece or Astro accessory barrel, and then slowly rotate the top half of the filter—it turns 360°—to achieve the results you desire.
The Optolong 1.25-inch Variable Polarizing Filter also works great to cut brightness when you are using your telescope for terrestrial observations or photography. If you have ever done photography through a SLR or DSLR camera, you may have already been introduced to the qualities of a polarizing filter, since it is a very popular accessory for polarizing the light and making the sky appear bluer. You will especially appreciate a polarizing filter when viewing over water or photographing a scene that includes a river or body of water. Simply turn the filter until you achieve the most glare-free results—you will really see the difference.
- Brand: OPTOLONG
- Type: Variable Polarizing
- Size: 1.25-Inch
- Substrate Thickness: 2mm
- Clear Aperture: 26mm
- Surface Quality: 60/40
- Surface parallelism: 1/4λ
- Parallelism: 30"
- Thread: M28.5*0.6
- Single Thread: Yes