: The image plane is where the image is first formed. : It is also called the Focal Plane. It almost always : found inside the focuser and you can consider the : opening of the focuser towards the scope as the largest : image plane that you can get. The actual image plane : is to be found in your EP where the aperture stop is. : That is that odd ring that you just quite can't figure : out what it is for. Looking through the EP into a bright : field (in the daylight for example) will show a sharp edge : to the field of brightness when the eye is close enough : to the EP. Putting something up to the same place as that : ring will bring the object into focus! : Alternatly, you can use 1" as the dimension for a 1.25" : focuser or 1.75" for a 2" focuser for the image plane : dimension.

• vegeta - kathy_roberts/">kathy roberts - December 10, 1998 - 17:55 UTC