Customer comments/photos.
Updated 3/26/24


Imaging Newtonians

Apertura Type Dobsonians

ATM Altitude and Azimuth
Bearing Parts

Laminate rings and strips.
Teflon pads.
Azimuth bolt assembly kits

Sharper Image Masks

Primary:Fix Turned Down Edge.    
Aperture: Eliminate spider spikes.

Primary: Remove mirror clip flare.
Spider: Remove diffraction spikes.

Premium Mirror Cells
for 6" to 13.1" mirrors.

Each cell design calculated to optimize your mirror's performance. Eliminates mirror-clip aberrations for true circular aperture.

Clamshell & Rotating Rings

For Dobsonian mounts
For Equatorial mounts

Altitude Bearings 

Friction control capture with Incised bearing channel.

Undersized bearings balance/motion problems.

Altitude bearings on a telescope are equivalent to balance poles for tightrope walkers. Poles spread the walker's balance out over a greater width. Too short a width (a short or no pole) results in instability. Imagine being pushed at the shoulders with your feet next to each other, you are very unstable. Larger altitude bearings spread the footing and weight, widening and lowering your telescope tube's balance point. Larger altitude bearings also provide finer incremental movement, each degree being futher apart where supported.


12" Big Bearings.

Under-balanced factory bearings.

5" Bearings Upgrade
An easy move to 12" bearings.

Many mass manufactured Dobsonian telescopes use 5" to 5-1/2" altitude bearings with inherent balance problems. This 5" Bearings Upgrade will improve balance, motion, and also add a friction/lock.

Designed to easily attach directly onto your tube's small bearings, we customize the bolt holes to match your existing size and pattern. Big The 5" bearings upgrade can fit flat onto your existing bearings.

Standard 12" Bearing Internally Mounted.

Carry handles are built in.

Standard 12" Bearing (unsanded).

Standard 18" bearing

Standard Bearings
12" and 18".

Standard 12" and 18" altitude bearings have incised channels for fine tuning guides. Bearing designs cutouts allow easy lifting and carrying of your telescope. Custom cut Inside braces precisely fit and clamp to the outside diameter of your telescope tube outside diameter. Choose among these options:

  • 3/8" center bolt hole for attaching to tube.
  • Holes to mount to your existing tube ring set.
  • No mounting holes (drill your own).
  • Attach inside mount side-walls.
  • Attach outside mount side-walls.
  • Curved interiour braces with tube matched mounting holes.
  • Can attach to existing small bearings.
  • Fine tuning friction guides and incised bearing channels.
  • Other custom sizes upon request.

What you get (depending on which item you order): all parts included. Bearings, supports, support screws, teflon, laminate strips, fine tuning assembly.

What you need: Glue for laminate (contact cement), Philips screwdrivers (#12 and #4) and longer attachment bolts if necessary.


5" Bearing Upgrades
5BUK 5" Bearings Upgrade Kit  $60
5BUF 5" Bearings Upgrade Finished $110
Standard 12" Bearings
S12K Standard 12" Bearings Kit  $58
S12SK Standard 12" Bearings with Supports Kit $87
S12F Standard 12" Bearings Finished  $87
S12SF Standard 12" Bearings with Supports Finished  $107
Standard 18" Bearings
S18K Standard 18" Bearings Kit   $67
S18SK Standard 18" Bearings with Supports Kit $121
S18F Standard 18" Bearings Finished $103
S18SF Standard 18" Bearings with Supports Finished $152


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