If the view is shaky or jumpy when the draw tube is racked in or out, or flexes when heavier eyepieces or accessories are introduced, your focuser can make observing almost impossible. A quality focuser should provide precise positioning of the eyepiece or camera to within .002 inches. Focusing should be smooth and easy, without any backlash, so the telescope doesn't vibrate or shake, even at higher magnifications. A decent focuser should be able to handle the weight of today's multi-element eyepieces, as well as a DSLR or standard CCD camera.
At High Point, you’ll find affordable rack and pinion focusers and more advanced Crayford focusers. We also carry highly precise electric and motorized focusers. These are excellent because they virtually eliminate vibration by removing the need to touch the telescope. Electric and motorized focusers may also come with a controller and/or different speed settings to bring convenience and variety to your viewing experience.
Starlight Instruments produces a range of micro focusers for a number of brands, including Meade and Celestron. For example, the Starlight Instruments FeatherTouch Fine Micro-Focuser Upgrade for 11" Celestron SCT Telescopes is easily installed and allows for both standard and 1/10th speed focusing for ultra-sharp views.
If you’re one of the many satisfied owners of a ZWO Off-Axis Guider, you might want to try the ZWO 1.25" Non-Rotating Helical Focuser. This inexpensive accessory attaches to the OAG and allows you to fine-tune your focus without rotating your camera, making it an essential tool for astrophotographers.