The officer at left in the 1894 issue field cap is Oberleutnant Otto Eggers, though probably just a lieutenant when this picture was taken. He was very young when he came to Southwest Africa in 1894, though it is hard to credit that he was as young as sixteen, if we go by the vital statistics presented for him by Klaus Dierks. He was formerly in the Lower Saxony Field Artillery Regiment No. 46, and served as Besirkschef at Okahandja. Eggers wrote a journal that was posthumously published, for he was among the officers and men of Maj. von Glasenapp's East Section killed at Owikokorero on March 13th, 1904.
The man at the center is Dr. Friedrich von Lindquist, who arrived in the colony at the end of 1893. As one of Governor Leutwein's deputies he was responsible for administering the central Windhoek district and was also a judge. Lindquist was appointed a German consular officer at Cape Town during the Boer War in 1900 and promoted to consular General in 1902. He succeeded Lt. Gen. Lothar von Trotha as Governor of Southwest Africa in 1905 during the Nama uprising and remained in the colony until 1908. He actively promoted the introduction of karakul sheep farming and established a vast wildlife reserve in Northwestern Namibia in 1907 that included what is now Etosha National Park.
The officer at right in the 1891 issue kepi is identified as Major Schwabe. Kurd Schwabe arrived in the colony as a Leutenant in 1893, and held Haupmann's rank as late as 1903. He participated in military operations against the Witbooi Nama and the ovambanderu and served as Besirkschef in Okahandja and Otjimbingue before leaving Southwest Africa in 1897. He subsequently served in the Seebataillon during the Boxer Rebellion and returned to Africa during the Herero War (I believe as an adjutant and staff officer). Schwabe wrote extensively on colonial warfare and his various campaigns and taking a large number of photographs during his travels. Oberstleutnant Schwabe died in 1920 of hepatitis contracted during WWI in Palestine.