The MEADE #1220 Field De-Rotater

A revolutionary accessory! MEADE has been inspired by the professional observatory working in altazimuth mode, to conceive the working of this device. It is thanks to it that the CCD imaging in now possible in altazimuth mode.

THIS ACCESSORY CAN BE ONLY USED ON THE MEADE LX200 OF LAST GENERATION WITH V3.34 AND V8.37 SOFTWARE .

POLAR AND ALTAZIMUTH MODE

In the majority of cases, all night, with a CCD camera or classic films, for deep sky pictures, starts with the polar alignment. The Bigourdan method  is used by the amateurs; for the other, the polar viewfinders permit a good and fast alignment. All these telescopes have a German mount or a fork on equatorial wedge. But in most cases, the polar alignment is long. The LX200 possesses in its software, a polar alignment with computer help that is drifted of the Bigourdan method. To have tested it, i can tell you, you pass a lot of time (about 1h00 to 1h30).

For the CCD, the polar alignment must be very fine to avoid the loss of the star used for the guiding, especially if you use a CCD AUTOGUIDER.

With the altazimuth mode, the setting up of the telescope is simple and fast. When you buy a LX200, it is delivered in altazimuth mode. But, if the altazimuth mode is perfect for visual observations this is not the case for CCD imaging. You will have a field rotation effect. On the pictures, stars will be characterized by a circle, due to the field rotation.

For resolve this problem with the LX200 it was necessary to buy the super equatorial wedge. Now you can replace the super wedge by the MEADE Field De-Rotater.

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