Off-Axis Guider - User’s manual
Thank you for purchasing the Atik Off-Axis Guider (OAG). With it, you will be able to autoguide using a secondary camera, and, since
the autoguider was designed to be attached to our EFW2, it will act as a single, rigid unit. This is of enormous importance in eliminating differential flexure, something that is the nightmare of any astrophotographer.

Getting to know your OAG
The OAG was designed to be attached directly to the EFW2, but with the correct adapters it may be possible to attach it to T-threadedaccessories. The OAG system is as follows:

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1 - Focusing ring; 2 - T-thread extensions; 3 - Lockingscrew; 4 - Pickup prism

5 - 2” to M54 adapter; 6 - Main body; 7 - 4mm, 7mm and15mm T-thread extensions

Attaching your OAG to the EFW2
Attaching the OAG to the EFW2 is a very simple task. Just follow these instructions:

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1- Unscrew the 3 grub screws that cover the holes on
the EFW2 front cover.

2- Align the OAG with the 3 holes and attach it to theEFW2, using the 3 supplied screws.

343- Verify that the 3 screws are in place. The OAG should
now be securely attached to the EFW2.

4- If you need to take it off, just undo the screws. Notethat to change filters there’s no need to take the OAG off.

Using your OAG
The OAG is very easy to use and adjust. Looking at all components individually:

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The main body (6) is where all the action happens. The pickup prism bends the light path through 90º, to the guide camera. You canattach the OAG to the telescope using the 2” adapter (5). Also, a kit of extension rings (7) is supplied, so that different guide cameras
can be used with different main cameras, in several different combinations. The choice of extension to use is governed by the maincamera, guide camera, pickup prism position and even the telescope. You will need to do some experimentation to find the rightcombination of rings. Both the OAG and the rings have T-threads, so they will fit any camera with T-threads.

To adjust the pickup prism, you need to slightly undo the locking screw (the access hole is just below the locking screw), making surethat you undo it only “slightly”. There’s a captive recess that will prevent the prism support to falling, but this will not work if the screwin undone too much, causing the support to fall out of place.
Use your finger to move the prism support to the desired position, and then tighten the locking screw. Again, the correct position will
depend on the main camera and telescope used. As an example, an Atik 11000 will probably need the prism all the way in, to avoid
shadows, and if an SCT is used you’ll probably want to lower the prism as much as possible, to get better star shapes.

Focusing your OAG
One of the great features of the Atik OAG is the extremely smooth focus mechanism:

Simply adjust the focusing ring counter-clockwise, and the camera support will smoothly and precisely go up: turn clockwise, and it
will go down. It’s as easy as that! When focused, just tighten the locking ring slightly (don’t over tighten!), so that the assembly keeps
rock solid! There’s a total travel of about 5mm which, in addition to the supplied rings, will be enough to make it easy to focus yourguide camera.