Right - The Turkish Army's Field brown uniform adopted by the 1st Engineers' Battalion before 1908 (extracted from Askeri Müze ve Kültür Sitesti Komutanligi. (1986) Osmanli askeri teskilat ve kiyafetleri: 1876-1908 [Ottoman military organization and uniforms] Yayinlari). Note the distinctive:
There was also a 'dark brown version' of the blue dress uniform designed and issued for a short period, prior to 1908 (discussed below), as a for-runner to the lighter brown field uniform trailed by the 1st Engineers, which became the basis of the 1909 field brown uniforms of the WW1 period; and this uniform re-appeared in 1914 as en emergency issue.
The British General Staff. (1995) 1916 Handbook of the Turkish Army. Battery Press (Nashville), states (p.63): "On mobilisation, 1914, all sorts of uniforms made their appearance, ... dark brown with red piping".
Right - The Macedonian Army battalions were dressed in the Turkish Army's Field brown uniform adopted by the 1st Engineers' Battalion before 1908 (discussed above). According to this NYT article, these soldier also wore 'white leggings' and 'sandals'; these are likely the traditional slip-on wool felt boot-socks, with leather shoes. The wearer winds black tap or leather strap around the boot-socks in order to secure these more.
Right - Enver Pasha, in 1908 when he was a Bimbashi (Major) in the Ottoman Imperial General Staff. He is modelling the newly designed field brown tunic, which had been tested by the 1st Engineering Battalion, in 1908. There are several pictures of Enver Pasha wearing this uniform, taken from a number of angles. In this particular picture, he is wearing his General Staff collar badges. The early brown field uniform from 1st Engineering Battalion, and retained items such as:
Right - The picture of Enver (above) features prominently this buckle type which appears very similar to a type assumed to be a WW1 Emergency Issue type, first seen in 1916; however, as it is seen in the 1908 photograph it was likely a test version befor the 1909 German buckles were later introduced, as it has the same prong fittings on the back (as found on a German buckle). Prior to 1908, French field equipment was used in the Ottoman imperial army.
Above - The picture of Enver (above) features a white over red armband. In Mesut Uyar, and Edward J. Erickson. (2009) A Military History of the Ottomans. Greenwood: 197, a photograph of “Officers of a Macedonian garrison with some civilians, proudly showing the armlets of the 1908 Constitution Revolution.” This shows the armbands also displayed a ribbon rosette (Below).
Above - Army Flag of the 'Young Turks' Movement' (from a recent Herman Historica sale).
Left - Hung on a pain red ribbon the 1908 Revolution 'donation' copper medal. Struck by civic athorities for public sale supporting the revolution.
The only modern account of the fate of the IG is actually contained in a New York newspaper account, from 1908. This is the - Foreign Correspondence’s "SOLDIERS OF TURKEY FAVOR NEW REGIME", THE NEW YORK TIMES (December 27, 1908).