Astro0Stuff ~ TelescopeMart.com
* Delivers a 3x magnification boost to any 1.25" eyepiece
* Great for lunar and planetary observing
* Perfect for extracting higher powers from short-focal-length telescopes
* Accepts standard filters
* One-year limited warranty
For those observing targets and applications where you need more power than your telescope eyepieces alone can provide, we offer the 1.25" 3x Orion Tri-Mag Barlow Lens. It gives a big 3x magnification boost to any 1.25" telescope eyepiece it's used with. This is desirable for lunar and planetary observing and for extracting higher powers from "fast" telescopes such as f/5 and f/4 refractors and reflectors. For long-exposure astrophotography, the power amplification provided by the Tri-Mag allows more precise guiding and use of a shorter guide telescope, such as a rich-field refractor (e.g., the Orion ShortTube 80). With the Tri-Mag barlow you can use longer-focal-length telescope eyepieces to achieve high powers, which offers the benefits of better edge sharpness and eye relief than you'd get using the equivalent high-power eyepiece without the barlow.
The Tri-Mag utilizes a multi-coated achromatic "negative" lens that effectively triples the focal length of the telescope's optics. The housing is precision machined from aluminum stock and black anodized to a hard finish. Both the housing and the chrome portion of the barrel are glare threaded and blackened inside to provide maximum contrast. The lens end of the barrel is threaded to accept standard filters.
Power-up your eyepiece collection and your telescope's performance with the new 1.25mm 3x Orion Tri-Mag multi-coated Barlow Lens.
Length, 5". Weighs 5.8 oz. One-year limited warranty.
Please note this product was not designed or intended by the manufacturer for use by a child 12 years of age or younger.
Download a PDF file of the Instruction Manual for this product. Requires Adobe Reader version 3.0 or higher.
Lenses are coated with an anti-reflective material to ensure that as little light as possible is reflected away, thus more gets to your eye. Good lenses are at least "fully coated," with a single layer of magnesium fluoride applied to each air-to-glass lens surface. Multiple layers of coatings are even more effective; the term "multi-coated" means one or more lens surfaces have multiple coatings. "Fully multi-coated" is superior because all lens surfaces are multiple-layer coated. Mirror star diagonals are coated with a reflective material similar to telescope mirrors in order to reflect the light into the eyepiece. Standard aluminum coatings reflect between 88%-92%, and enhanced aluminum reflects 97%. Dielectric coatings use a different process to deposit a coating that reflects 99% of the light. In addition to the higher reflectivity, Dielectric coatings are much more durable than aluminum coatings, so they last longer and can be cleaned with less risk of damage.
Instead of a single thumb screw locking the eyepiece in place, a brass ring compressed by a thumb screw secures the eyepiece. This spreads clamping force over a larger area of the eyepiece's barrel, which provides a better connection. The compression ring also prevents the tip of the thumb screw from producing unsightly scratches and divots on the eyepiece barrel.
Barrel size 1.25in.
Magnification factor 3
Number of elements 2
Filter threads Yes
Clear aperture 24mm
Compression ring No
Weight (oz.) 5.81
Height 5.0 in.
Warranty One year