Is it permissible for a married man to record a video of intercourse with his wife to stimulate him in subsequent instances if he was not stimulated during the act of intercourse?

The reason for the lack of activity should be sought out and addressed. Recording a video depicting conjugal relations is not advisable due to the possibility of others viewing it. A Muslim should avoid Western customs that contradict the natural disposition (fitra), and should know that Islam emphasizes concealment and protection of private matters between spouses.