The best way to set up any CCD is by using a parafocal ring on the CCD and on an eyepiece of similar size.  The DSI I Color has been compared by others to a 9mm and a 6mm eyepiece.  I believe 6mm is closer.  I don't have a 6mm, so I'm using a 9mm.  The biggest draw back is that you now have an eyepiece that can only be used with the ring on it.

Parafocal rings allow  you to focus the telescope with the eyepiece, tightening the ring upon best focus.  Then, without adjusting the telescope, place the CCD into the telescope and adjust the parafocal ring for best focus.  I don't use a parafocal ring on the CCD, but instead inserted the CCD all the way into the telescope.  My 9mm has the ring at about 1/2 of the tube length.  I think the focus is really good, but because the pixel size of the DSI is so large, it probably doesn't make that big a difference if the focus was slightly off.

Use the eyepiece in the telescope.  Use the hand controller or connected computer to move the telescope to the object of interest.  The telescope should track the object.  If alignment was perfect, the object should be centered in the view.  If not, move the telescope using the hand control or software until it is centered.  You may want to note the amount out of alignment you are.  If you setup the Telescope correctly, the object should in view with a 9mm. 

Replace the eyepiece with the CCD.  Verify the object is in view.  Adjust as necessary.  Inserting the CCD could ruin the alignment some or the CCD may have the imager offset from center.  Once you know this "offset", you can more easily perform that alignment for future observations.

When changing to a new object, you normally would go back to the eyepiece.  But if your alignment is good, you may be able to use the controller and make final adjustments for centering via the on screen live display.  My goal is to find out what it takes to allow me to do the latter.  The whole process is so much faster without changing between the CCD and eyepiece.

[ Home ] [ Up ]

PS - If you find anything on this page that is copyrighted material and we did not give an appropriate copyright notice for the owner, first realize that it is an oversight, as we are not trying to claim credit but for only a few of the pictures on this site.  Then we ask you to please let us know about the item in question. And finally, also realize that this is a private and non-commercial and hopefully educational site.  So buzz off.

Copyright © 2007, Gary Gorsline.  All Rights Reserved