Sets a repeatable, precise focus position for any 1.25" accessory Ideal for parfocalizing a set of eyepieces Reduces time spent refocusing when switching between accessories Securely clamps onto 1.25" barrels with a locking screw Description FAQ Specifications In the Box Downloads Warranty Baader 1.25" Stop-Ring The Baader 1.25" Stop-Ring is a fundamental accessory for any observer who uses multiple eyepieces, filters, or cameras, solving the problem of achieving consistent focus. This simple collar allows you to set a hard stop for any 1.25" accessory, ensuring it returns to the exact same focal point every time you insert it into your focuser or diagonal. Baader 1.25" Stop-Ring: Set Repeatable Focus Positions By clamping the ring onto the barrel of an eyepiece, you create a physical shoulder that rests on the top of your focuser drawtube or diagonal. This makes any set of eyepieces effectively parfocal; after focusing the first eyepiece, you can install rings on the others and adjust their positions so they all snap into focus without further adjustment. This saves significant time at the telescope, especially during planetary observation or public outreach. The utility extends beyond eyepieces. You can use a stop ring on the nosepiece of a planetary camera to return it to perfect focus after swapping in an eyepiece, or on a barlow lens to maintain a consistent magnification and focus position. It's a simple, effective tool for improving the efficiency and precision of your observing sessions. What is the primary purpose of the Baader 1.25" Stop-Ring? The Baader 1.25" Stop-Ring, also known as a focusing collar, is designed to create a fixed, repeatable focus position for any 1.25" accessory. By locking it onto an eyepiece or camera barrel, you ensure that the accessory stops at the same point in the focuser every time, eliminating the need to refocus when swapping equipment. How do I use the Baader 1.25" Stop-Ring to make my eyepieces parfocal? First, insert your highest-power eyepiece (or the one that requires the most "in-focus") and bring it to a sharp focus. Lock your telescope's focuser. Carefully remove the eyepiece without moving the focuser, slide a Baader Stop-Ring onto its barrel until it rests against the focuser top, and tighten the ring's screw. Repeat for your other eyepieces, bringing them to focus and then setting the ring's position. Now, you can swap between them with minimal to no refocusing required. When viewing Jupiter, how does the Baader 1.25" Stop-Ring help when switching eyepieces? When observing Jupiter, you might use a low-power eyepiece to locate the planet and its moons, then switch to a high-power one to see cloud bands and the Great Red Spot. By pre-setting the focus position on both eyepieces with a Baader Stop-Ring, you can make this switch nearly instant, keeping the planet in the field of view and perfectly focused without fumbling with the focus knob in the dark. Will the Baader 1.25" Stop-Ring fit any 1.25" eyepiece or accessory? Yes, the ring is designed to work with the standard 1.25" (31.75mm) barrel diameter used for the vast majority of astronomical eyepieces, barlows, and small cameras. It slides over the barrel and can be locked in any position. Could the Baader 1.25" Stop-Ring scratch my eyepiece barrels? The ring uses a locking screw to hold its position. While effective, over-tightening the screw on a delicate chrome or anodized barrel could potentially cause a small mark. It is best practice to tighten the screw just enough to prevent the ring from slipping, rather than applying excessive force. Can I use the Baader 1.25" Stop-Ring with a planetary camera? Absolutely. It's an excellent tool for astro-imaging. You can achieve perfect focus with an eyepiece, then swap to your camera which has a stop ring pre-set to the same focal plane. This ensures your camera is already in focus the moment you insert it, saving valuable time capturing data on targets like planets and the Moon. Accessory Size 1.25" Part Type Focusing Stop Ring / Collar Net weight (kg) 0.02 Screw Type 2x M4 clamping screws Compatible Brands UNC, Baader Planetarium, Celestron Clamping System Screw clamps Inner Diameter / Clear Aperture (mm) 31.75 (1¼") Outer Diameter 42.5 Type of Adapter Variable Focusing Optical length (mm) 4.8 mm T-2 Part # 30 Inner Connection (eyepiece/-camera-sided) ø 1¼" (31.75 mm) Inner Connection (lens sided) ø 1¼" (31.75 mm) Baader 1.25" Stop-Ring × 1 Baader Planetarium Astro T-2 System Connections Overview Baader Planetarium Astro T-2 System Parts List Baader Planetarium Warranty Policy
