Explore Scientific 2x Focal Extender – 2″
The Explore Scientific 2x Focal Extender will extend the focal length of any 2″ eyepiece to bring you fantastic magnifications for astro-imaging or visual observations. The optics of the 2x Focal Extender are fully multi-coated using Explore Scientific’s EMD enhanced coatings. All elements feature blackened edges to minimize reflections yet increase contrast for beautiful, clear views.
By using a standard Barlow or tele-negative lens to enhance your optical system’s magnification, the results you get will be reliant upon the placement of the Barlow in the optical chain. For example, if you place a 2x Barlow Lens in front of your diagonal instead of behind it (Barlow-Diagonal-Eyepiece as opposed to Diagonal-Barlow-Eyepiece), you won’t achieve 2x magnifications in both configurations. Magnification differs with placement. However, with this Explore Scientific 2x Focal Extender, magnification is consistent even when the distance is altered. It can be placed anywhere in the optical chain between an eyepiece or a camera. 2x magnification means you will get 2x magnification.
When it comes to imaging, this is a critical difference, because you may want to introduce an accessory like a flip mirror or filter wheel in between the Focal Extender and a CCD camera, which would increase the distance to the focused image. This difference in design allows users to rest easy, whether they are pumping up the magnification of a lower power eyepiece for visual observations or using their Explore Focal Extender in imaging applications.
Explore Scientific Focal Extender Highlights
More Magnification Choices without Sacrificing Eye Relief
A quality Focal Extender adds some genuine flexibility to your telescope accessory roster. First, it enables the magnification increase of any eyepiece you already own that has a barrel size identical to that of the focal extender. In other words, 3 eyepieces give you 6 magnification options with the addition of a focal extender. Second, lower magnification eyepieces usually have better eye relief than higher power models. By using a focal extender in lieu of a higher magnification eyepiece, you get to enjoy the comfortable eye relief of the lower power eyepiece. For observers who wear eyeglasses, or for those with fast telescopes who can really push high magnification eyepieces, this can be a significant perk.
Optimized Optical Design
Explore Focal Extenders are optimized through each design, fabrication, and testing process to produce high contrast, high-resolution images.
Durable Coatings & Finishing Touches
All four elements of Explore Scientific Focal Extenders are fully multi-coated using Explore EMD enhanced coatings for bright, sharp images. In addition, every element features blackened edges to minimize internal reflections and increase contrast.
Tapered Barrel For Extra Security
The insert barrel of each extender is double-tapered to allow smooth insertion to, and removal from, a telescope’s eyepiece holder, focuser or diagonal. However, the wide dimension of the taper helps prevent the focal extender from falling out of the telescope should the set-screw holding it in place become loose. The barrel is threaded to accept 2″ filters.