AstroSystems Focusers

Phase 4 Focuser

AstroSystems has worked for over seven years researching and developing the most advanced focuser on the market! Phase 4 has the best stability and weight handling capacity of any visual focuser. Phase 4 incorporates the smooth action of 4 precision ball-bearings and high draw tube loading to eliminate image shift and increase stability. High draw tube loading increases weight capacity for handling any eyepiece combinations, cameras or CCDs. AstroSystems has maintained the low 1.50" profile you've come to expect. Recommended for eyepieces, astrophotography and CCD cameras up to 5 pounds.

Among the Phase 4 features are:

• Effective "cog drive" timing belt eliminates backlash and gives positive lifting capability in any weather.
• The drawtube rides on precision stainless steel ball bearings.
• Ultra-low height to allow you to optimize your secondary mirror size for maximum field illumination and contrast.
• Smooth, positive focusing geared 3 to 1 to give you precise focusing at any magnification.
• Leveling screws allow focuser to fit any tube diameter and make collimation easy and accurate.
• Made in the USA of corrosion-proof materials. Strong and trouble-free.
• Tools, installation instructions and stainless steel mounting hardware are included.
• 2" to 1.25" reducer adapter, threaded to accept 48mm filters. Substitute the ultra-low adapter at no charge and lower the effective profile with 1.25" eyepieces to 1.0"! The adapter can be purchased separately (see below).
• Five year unconditional warranty and a 30-day money back guarantee.

Field tested and proven! Phase 3 is a 1.50" (minimum) profile, visual focuser utilizing a smooth friction drive. The same innovative design features and AstroSystems quality as the Phase 4 except the Phase 3 drawtube rides on Teflon. Phase 3 is ideal for visual use with eyepieces under two pounds.

Specifications:

	Height:	Min. 1.50" (38 mm) Max. 2.7" (68 mm)
	Travel:	1.2" (30 mm)
	Weight:	16 ounces (0.45 kg.)
	Base:	3.0 x 4.4" (76 mm x 112mm)
	Capacity:	2.5 lbs. (1.1 kg.)
	Accuracy:	0.0002"../../in. travel or less side play with 2lb. load
	Ship Weight:	3 lbs.

Phase 3 Focuser / Slide Tube

For additional focus travel, an integrated 2.0" ID slide tube within an enlarged draw tube, gives over 3.0" of focus travel while keeping the profile to 1.6". You can easily remove the slide tube to change eyepieces or filters and then pre-focus in seconds. The slide tube option has the same base dimensions and capacity as the Phase 4. Weight 4 lbs.

Standard Eyepiece Adapter 2" to 1.25"

This precision-made quality adapter allows one to employ 1.25" diamter ocualrs and accessories into a 2" diametr focuser. Anodized aluminum, threaded for 48mm filters with a polished stainless steel set screw. Weight 1 lb.

Ultra low Eyepiece Adapter - 2" to 1.25"

You can lower the profile of your 1.25" eyepiece another 0.5" below the drawtube. The ultra low eyepiece adapter works with any 2.0" focuser. The 1.25" eyepiece position is inset down into the adapter, dropping the eyepiece height 0.5". This allows another 0.5" of focus travel and optimization of the secondary mirror size. Anodized aluminum, threaded for 48mm filters with a nylon set screw.

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