William Optics RedCat 71 WIFD APO f/4.9 This latest version of the Redcat 71 features the same tried-and-tested optics as previous versions, so it provides high-resolution images when used for astrophotography or wildlife photography. Its fast f/4.9 focal ratio and compact size ...William Optics RedCat 71 WIFD APO f/4.9 This latest version of the Redcat 71 features the same tried-and-tested optics as previous versions, so it provides high-resolution images when used for astrophotography or wildlife photography. Its fast f/4.9 focal ratio and compact size make it ideal for convenient wide-field astrophotography, and the WIFD (William Optics Internal Focuser Design) is integrated inside the main tube assembly, so no focuser drawtube movement is visible from the outside.
One of the most significant benefits of the WIFD is that you can add several heavy accessories to your imaging train, such as a large filter wheel or rotator, without worrying about sag from the telescope focuser drawtube and the resultant tilt of the sensor with reference to the optical axis. Designed primarily for astrophotography, the RedCat 71 provides a flat image plane (without needing an additional flattener), an image circle over 45mm, excellent colour correction and pinpoint stars.