The Celestron Deluxe Tele-Extender is an SCT imaging accessory that allows you to take pictures through an eyepiece, for high magnification shots of the Moon, the planets, and the Sun (with the proper filtration).

To use the Deluxe Tele-Extender, remove the diagonal or any other accessories attached to the visual back of your telescope.  Insert the 1.25” eyepiece you want to use into the visual back and lock it firmly into place with one of the setscrews.  The eyepiece must have a diameter smaller than 45 mm, which is the inside diameter of the Tele-Extender.  Many eyepieces are too large, so double-check the fit before you begin your astrophotography session.  For the most secure connection, remove the second thumbscrew from the visual back body and then slide the Tele-Extender over the inserted eyepiece as well as the visual back.  When engaged, the two thumbscrews on the Tele-Extender clamp onto the visual back to hold everything firmly in place, assisted by a safety shield that keeps the thumbscrews from loosening during use.

The camera side of the Deluxe Tele-Extender accepts a standard T-ring (sold separately).  Remove the lens from your digital SLR and attach the appropriate T-ring.  Screw it onto the t-threads of the Extender, make sure everything is tight and locked down correctly, and you are ready to take a picture.

Remember, the image is not the only thing that will be magnified when doing eyepiece projection photography!  Any problems with seeing conditions will become much more apparent, as will unintended movements of the telescope.  Extra precautions taken to keep your telescope stable will help you achieve better results, including the use of a cable release to depress the shutter button for you.  With a little experimentation, you will be taking high magnification images of solar system and terrestrial objects in no time!