The present application relates generally to systems and methods for using machine vision to provide information on one or more aspects of an additive fabrication device, such as calibration parameters and/or an object formed by the device or in the process of being formed by the device. According to some aspects, a method is provided for calibrating an additive fabrication device. According to some aspects, a method is provided for assessing at least a portion of an object formed using an additive fabrication device. According to some aspects, a method is provided for fabricating a second object in contact with a first object using an additive fabrication device. According to some aspects, an additive fabrication device configured to perform one or more of the above methods may be provided.