Like any other camera or eyepiece the Revolution Imager must be focused in your telescope to use it. Here's some tip so achieving a good focus.
If you have trouble achieve focus when using the nose piece and focal reducer in your telescope here's some things you can try removing the extension part of your noise-piece you have a two-part nose-piece or you can try removing the 0.5x focal reducer.
high-gain is the game
We recommend using a high-gain setting when focusing. These high-gain settings will help you find a star or stars to help you focus even if you are far out of focus.. The image here shows that the camera is very far out of focus with the "star donut" being very large. A High-gain mode will help you see these donuts better and will show them to you faster giving you the fast feedback you need when focusing.
These are the high-gain settings we recommend. If you need help finding these items in the menu please see our menus help page. Don't forget: when changing settings, use the save/exit function to lock them in.
try using a bahtinov mask
A bahtinov mask is a small device that you place on the front of your telescope that helps you achieve perfect focus.
When using a bahtinov mask it will add "spikes" to bright stars. Changing focus changes the pattern of the spikes and when the star spikes look like this image that means you have good focus.
Because Polaris is an easy-to-find year-round double star for those of us in the northern-hemisphere it makes a great star to use as a focus aid. In this image you can see Polaris' companion star and is a good indication that you have a good focus.