T-Adapter Universal - 1.25 inch With these Celestron T-adapters, 35mm SLR cameras can be connected to the primary focus of a telescope or spotting scope. The adapter is inserted and fixed into the 1.25" eyepiece holder instead of the eyepiece. This allows you to take terrestrial photographs, but also lunar and planetary images. For deep sky photography, you will need an additional guide scope and a T-ring for the respective camera in addition to the T-adapters.