AstroSystems Focusers

Phase 4 Focuser

AstroSystems has worked for over thirteen years researching and developing the most advanced focuser on the market!  The Phase 4 has the best stability and weight handling capacity of any visual focuser in it's price range.  The Phase 4 incorporates the smooth action of four 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 1.55" profile you've come to expect.  Recommended for eyepieces, astrophotography and CCD cameras up to 5 pounds. 

The Phase 4 features are:

• Effective "cog drive" timing belt which eliminates backlash and gives positive lifting capability in any weather. 
• The drawtube rides on precision stainless steel ball bearings. 
• Ultra-low height allows 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 the 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" - 1.25" adapter threaded for 48mm filters.  Substitute the ultra-low adapter at no charge and lower the effective profile with 1.25" eyepieces to 1.05"! 
• Lifetime unconditional warranty and a 30-day money back guarantee. 

• Height............Minimum 1.50" (38 mm), maximum 2.7" (68 mm)
• Travel............1.2" (30 mm)
• Weight...........17 ounces (480g.) 13 ounces without adapter (360g.)
• Base...............3.0 x 4.4" (76 mm x 112mm)
• Capacity.........5 lbs.  (2.3 kg.)
• Accuracy........0.0002"/in.  travel or less side play with 2 lb.  load

  $149.00

Shipweight...3 lbs.  Secure Order Now!

To see another picture of the P4 click here. 

Standard Eyepiece Adapter 2" to 1.25" (shown on right)

This precision-made adapter is made of anodized aluminum and threaded for 48mm (2") filters.  Our adapters now feature a compression ring.  This offers accurate and consistent retention of collimation tools and is non-marring on eyepiece barrels.

$29.00, Shipweight 1 lb.

Ultra low Eyepiece Adapter - 2" to 1.25"  (shown on left)

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 compression ring.  Supplied with hex key to tighten compression ring.

$29.00, ShipWeight 1 lb.

Secure Order Now!