Customer comments/photos.
Updated 6/1/24

ATM Altitude and Azimuth
Bearing Parts

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

Sharper Image Masks

Primary:Fix Turned Down Edge.    

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

Manual altitude and azimuth setting circles
Setting circles make finding your way around the sky easy. Here is how they work. 
We ask for these six example dimensions to design a custom azimuth circle fitting your telescope.
Prefer electronic setting circles? Contact us.

New: Rocker Box bottom board and ground board assembly with intergrated EZ-Azimuth Setting Circle.

Customized setting circles to fit your mount bearings.

Our manual setting circles

Laser inscribed 3mm birch plywood.
Simply glue to your bearings.
Altitude and azimuth pointers included.

Azimuth bearing setting circle:

One piece azimuth circles up to 23.5" O.D. Inquire with circle diameter and zip code for shipping cost.

Quarters or halved azimuth circles to 24" O.D.
and fit tightly around rocker box corners. Price includes shipping.

AZ-QC Azimuth quarters/half circles.
AZ-QC+Alt Above plus altitude circle.

AZ-FC Azimuth full circle.
AF-FC+Alt Above plus altitude circle.

Setting Circle Choice:
Azimuth Circle
OD/ID (up to 1" width, i.e. 18"/16"):
Altitude Circle
Focuser side telescope pointed North:
OD/ID (up to 1" width, i.e. 12"/10"):
An e-mail requesting a few simple dimensions will be sent after we receive your order.

Image above: setting circles inscribed on our altitude and azimuth bearings, azimuth pointer in inset.

Right image: two piece (split) azimuth circle notched for rocker box corners, altitude circle and pointers.

Azimuth circle for top of rocker box board.

Azimuth circle for round ground board.

Using Manual Setting Circles

 Using manual setting circles will allow you to place a target in your wide-field eyepiece or finder. This is the easy process for effective use:

Place a compass or phone with app against the front board on your mount. Align the ground board setting circle pointer with the 0 degree mark. Adjust the mount so the compass and ground board pointer N/0. The above example is using a phone app with the phone turned west (270 degree) putting N at 0.
It is useful to use a bubble level or app as it is important for assuring the altitude setting circle accuracy. Shim/adjust the mount feet as necessary.

Use a planetarium program or app like Star Safari that shows the Azm (azimuth) and Alt (altitude) for the objects you will observe. The arrow in the above example shows Messier 35 located at Azm 148 and Alt 75. Below shows the setting circles at the correct azimuth and altitude settings:


 This shows the azimuth circle turn so 148 is at the pointer.
This shows an altitude bearing with 75 at the pointer.
Look for your target in a wide field eyepiece. If it is not there use the star patterns on your chart/app and match them in your finder scope, you will already be very close to the target. Setting circles are a great tool, especially when observing in skies where few stars are visible to the naked eye.