Orion 8956, 8958 instruction manual 2a 2b 2c 2d, Figures 2a-d Unpacking the Optical Tube

2a

2b

2c

2d

Figures 2a-d:Unpacking the Optical Tube.

Grip-ring

Focuser body

Figure 3: Removing the focuser.

to thread directly onto the optical tube. It may be useful to experiment with different combinations during the day before heading out into the field. Choose a target over ½ mile away to ensure you are simulating distant focus.

If the focuser drawtube is fully extended and you are still unable to achieve focus you will need to install one or more of these extension rings. They are to be installed in-between the focuser and optical tube. In order to install the necessary extension ring(s) you will need to first remove the focuser from the optical tube. Be careful not to cross-thread these pieces when re-attaching adapters.

1.Remove the focuser by holding the focuser body with one hand while gently turning the knurled silver grip-ring with the other (Figure 3). Turn counter-clockwise to loosen.

2.Attach the extension ring of choice to the back end of the tube. The optical tube has external (male) threads. Subsequently you will use the end of the ring with internal (female) threads to attach.

3.The exposed threads on the back of the extension rings match that on the OTA to install additional extension rings or to reattach the focuser.

4.Once you have added the desired number of extension rings re-attach the focuser by aligning the silver grip-ring over the exposed extension ring threads and tighten by carefully turning clockwise (Figure 4a-d).

The wide variety of astronomical equipment available will require that you add or remove some or all of the extension rings. Individual setups will require different combinations of extension rings be used. In general, visual applications will require further extension than imaging. The examples listed and pictured below are of common scenarios. Some set- ups may require combinations different from those shown in Figure 4.

To set up any Orion StarShoot Deep Space imagers use all three (1 x 2" and 2 x 1") of the supplied extension rings to reach focus. For DSLR and most visual applications use 3" of

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