The next step up from this is simple approach is to guide the camera so that the stars appear as points of light rather than trails. Any telescope with a reasonable Right Ascension drive can be used for this, although it will need to be equatorially mounted (apologies to Dobsonian readers !!). In this mode we are still using the camera alone to do the imaging, that is we have not tried imaging through the telescope we will come to that later. Fix the camera securely to the telescope; use the manufacturers bracket if possible, but if not improvise !! It sometimes helps to keep the camera near the centre of gravity of the scope to avoid any unbalancing. It may also be necessary to adjust the position of any counterweight to allow for the weight of the camera.
Once the camera is fixed, the procedure is the same as for the unguided camera, but switch on the telescope drive to keep the camera pointing at the same area of sky and thus tracking the stars. Try exposures of 3 to 5 minutes. These will yield stars much fainter than those visible by eye, indeed it is quite easy to photograph stars down to magnitude 10 and fainter by this method.
Next - CCD Cameras
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