We report a pyrometer that operates at a mid-infrared wavelength range (7-8 mu m), where sapphire substrates are opaque and the reactant gases are transparent. The pyrometer also employs a novel "self-reflectance" method of emissivity correction, whereby thermal emission from the sample serves as a radiation source to measure its emissivity. The instrument was installed on a multiwafer Veeco D-125 MOCVD system and used to measure the emissivity-corrected temperature at a variety of GaN and InGaN deposition conditions. For a series of InGaN multiquantum well growth, the pyrometer was used to control the surface temperature at the critical InGaN deposition step, resulting in improved control of the photoluminescence wavelength. (C) 2008 Elsevier B.V. All rights reserved.