diff --git a/src/astro/illuminance.cpp b/src/astro/illuminance.cpp
index 3d39452..ce2d44a 100644
--- a/src/astro/illuminance.cpp
+++ b/src/astro/illuminance.cpp
@@ -30,7 +30,7 @@ double vmag_to_lux(double mv)
 
 double lux_to_vmag(double ev)
 {
-	return -14.18 - 2.5 * std::log(ev);
+	return -14.18 - 2.5 * std::log10(ev);
 }
 
 } // namespace astro
diff --git a/src/renderer/passes/sky-pass.cpp b/src/renderer/passes/sky-pass.cpp
index 2e0038c..42820a7 100644
--- a/src/renderer/passes/sky-pass.cpp
+++ b/src/renderer/passes/sky-pass.cpp
@@ -126,6 +126,8 @@ sky_pass::sky_pass(gl::rasterizer* rasterizer, const gl::framebuffer* framebuffe
 		// Convert apparent magnitude to lux
 		double vmag_lux = astro::vmag_to_lux(vmag);
 		
+		std::cout << "mag: " << vmag << "; lux: " << vmag_lux << "remag: " << (astro::lux_to_vmag(vmag_lux)) << std::endl;
+		
 		// Normalized color luminance and scale by apparent magnitude
 		double3 scaled_color = color_acescg * ((1.0 / color_luminance) * vmag_lux);