What is the main advantage of the Starlight Instruments TRUE 3.0" focuser?
It accepts 3" accessories: the drawtube opening on the visual side is greater than 3.0". It also carries Starlight's highest current site rating among its 2.5" to TRUE 3.0" focusers, 15-17 pounds.
What else do I need to mount the Feather Touch TRUE 3.0" focuser on my telescope?
This product is the focuser body only. To attach it to your telescope and use accessories, you will need to purchase two additional items sold separately:
- A telescope-specific tube adapter ring to connect the focuser to your optical tube.
- An end cap (such as a 2" compression ring for eyepieces or a threaded adapter for your camera) to connect your accessories to the drawtube.
Can the TRUE 3.0" focuser handle my heavy astrophotography camera and filter wheel?
If the total is within its 15-17 pound lifting capacity, yes. Add up the camera, filter wheel and other accessories, use the brake to hold position, and choose a threaded end cap for a secure connection.
How do I choose between the 1.5" and 3.5" travel options for the Feather Touch TRUE 3.0" focuser?
The choice depends on your telescope and imaging train's focus requirements.
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1.5″ (38.10mm) Travel: racked in 3.672" (93.27 mm) and racked out 5.368" (136.35 mm) from the mounting face; 3.69 pounds with the standard adapter and 2" compression ring end cap.
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3.5″ (88.90mm) Travel: racked out 7.368" (187.15 mm) from the mounting face; 3.99 pounds with the standard adapter and 2" compression ring end cap. It suits setups that switch between accessories with very different focus positions.
Can I use the TRUE 3.0" focuser for visual observing?
Yes. Starlight designed it to accept 3" viewing accessories, and a 2" compression ring end cap is available for 2" eyepieces. The 10:1 fine focus control helps at high magnification on planets like Jupiter or Saturn. Fit to your telescope depends on the tube adapter Starlight offers for it.
What does the M86X1 draw tube thread mean for imaging?
The draw tube thread is M86X1. Accessories attach through an end cap (sold separately), and a threaded end cap gives a more secure connection for reducers and cameras than a compression ring.
How does the 360-degree rotation on the TRUE 3.0" focuser work?
The focuser body sits inside a telescope-specific adapter ring (sold separately). By loosening the three gold thumbscrews on the adapter, you can rotate the entire focuser assembly smoothly to any orientation. Tighten the thumbscrews again once framed.
Can I motorize the Feather Touch TRUE 3.0" focuser later?
Starlight's motor systems are the HSM and the PDMS, run by a Starlight controller (sold separately). The focus knobs come off with a 1/16 hex key for a motor drive. The HSM30 suits the TRUE 3.0", and the PDMS-FTFF suits true 3" focusers.
What maintenance does the rack and pinion drive require?
Very little. The focuser ships with a thin film of grease applied to the rack and pinion system, and no further lubrication is necessary under normal use. The reduction assembly is lubricated during assembly and needs no further lubrication.
How do I install the Feather Touch TRUE 3.0" focuser on my telescope?
Installation involves first attaching the separate tube adapter to your telescope's optical tube, usually by screwing it on (on some telescopes, such as carbon fiber tubes, it is secured with screws). Then, you insert the focuser body into the adapter, rotate it to your preferred orientation, and tighten the three gold thumbscrews to lock it in place. The focuser manual provides detailed step-by-step instructions.
