GSO 1.25" 2.5x Apochromatic Barlow Lens # BL251
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Please note: Despite the product being specificed as a 2.5x barlow, a number of users have reported that this operates closer to 2.1 or 2.2x natively, although you can get close to 2.5x by sliding your eyepiece out of the holder a bit or adding a short extension.
Quick Overview
- GSO's 1.25" 2.5x fully apochromatic Barlow increases the magnification of each eyepiece and effectively doubles the number of eyepieces at your disposal
- Low profile maintains a comfortable viewing position
- Air-spaced, three-element, fully-multicoated ED lenses with excellent color correction, sharpness, and image brightness
- Precision-machined aluminum barrel with high-quality black-anodized finish and knurled ring to aid in handling
Product Details
If you need more power than your eyepieces alone can provide, we offer a new apochromatic 2.5x Barlow lens from GSO (Guan Sheng Optical) to give a big magnification boost to any 1.25" eyepiece it's used with.
Nothing has been compromised in GSO's latest and finest offering. This Barlow features an air-spaced, three-element, apo design with fully multicoated optics. The housing is precision machined from aluminum stock and black anodized to a hard finish. The lens edges and inner barrel are blackened to provide maximum contrast. The Barlow body includes a brass compression ring so that your eyepiece barrels are not marred by the captive set screw. The 2.5x model has a clear aperture of 23mm. For those who need a very high quality Barlow for all-round use, the 2.5x barlow is a very nice step up from the typical 2x achromatic barlows commonly found on the market.
Specifications:
- Barrel size = 1.25" (31.7mm)
- Magnification factor = 2.5x
- Weight = 3.5oz (99gm)
- Total height = 2.95" (75mm)
- End caps = 2
- 1.25" filter threads on bottom of barlow: No
- Made in Taiwan
Other Information
- Country of Manufacture: Taiwan
| Size Format | 1.25 inch |
|---|---|
| Magnification Factor | 2.5x |
| Number of Lens Elements | |
| Lens Coatings | Fully multicoated |
| Total Length | 2.95 inches / 75 mm |
| Length of Nosepiece | 1.18 inches / 30 mm |
| Outside Length of Upper Body | 1.8 inches / 45.7 mm |
| Insertion Depth | 1.57 inches / 40 mm |
| Max Diameter Excluding Thumbscrew | 1.92 inches / 48.8 mm |
| Clear Aperture | 0.88 inches / 22.4 mm |
| Weight | 3.5 oz / 99 g |
| Barlow Lens Cell Removable | No |
| Filter Threads at Bottom of Barlow Cell | No |
| Filter Threads Between Barlow Cell and Tube | N/A |
| Barrel Type | Smooth-sided |
| Compatible Agena Bolt Case (with Screw Removed) | 42x80 |
| Compatible Bolt Case (with Screw Attached) | 52x80 |
| Number of Thumbscews | 1 |
| Thumbscrew Thread Specification | M4x0.7 |
| End Caps (Subject to change without notice) | 2 |
| Compression Band/Ring in Eyepiece Holder | Yes |
| Country of Manufacture | Taiwan |
