It appears like the Sony A-mount has finally died, which isn’t that shocking given how long it’s been there.
It has been six years since Sony last issued an A mount camera, and seven years since they last published an A mount lens, and it appears that the company’s one-of-a-kind DSLT (digital single-lens translucent) series has been retired for the foreseeable future. Given the lack of progress in the Amount lens series over the previous several years, it is reasonable to presume the line has come to an end. Sony Japan has categorized all A-mount lenses as “discontinued.”
Even in light of the lack of progress, the news is not particularly shocking. Sony was unlikely to continue to support two different mounts, and the technology that underpinned the DSLT design, while intriguing, was made effectively useless by the introduction of on-sensor phase-detection autofocus. Sony was unlikely to continue to support two different mounts. The pellicle mirror (which was really not transparent) in the DSLT design enabled incoming light to be divided into two routes, one of which was sent to a phase-detection autofocus sensor and the other of which was routed to a sensor that also served as an electronic viewfinder.
Other than additional complexity, the disadvantage of this method against a current on-sensor phase-detection system was a loss of approximately one-half stop of light reaching the sensor since part of it had to be utilized for focusing. Despite this, the Amount line was quite popular, and it got increasingly complex towards the conclusion of its run. While Sony has not yet released an official announcement on its demise, it is safe to presume that this is the end of the line for the company and its products. The Amount has been around for far longer than Sony’s involvement with it, having been launched by Minolta in 1985.