diff --git a/src/gl/renderer/gl_postprocess.cpp b/src/gl/renderer/gl_postprocess.cpp
index 30c0000d3..c504088f4 100644
--- a/src/gl/renderer/gl_postprocess.cpp
+++ b/src/gl/renderer/gl_postprocess.cpp
@@ -133,6 +133,17 @@ CUSTOM_CVAR(Float, gl_ssao_exponent, 1.8f, 0)
 	if (self < 0.1f) self = 0.1f;
 }
 
+CUSTOM_CVAR(Float, gl_paltonemap_powtable, 2.0f, CVAR_ARCHIVE | CVAR_NOINITCALL)
+{
+	GLRenderer->ClearTonemapPalette();
+}
+
+CUSTOM_CVAR(Bool, gl_paltonemap_reverselookup, true, CVAR_ARCHIVE | CVAR_NOINITCALL)
+{
+	GLRenderer->ClearTonemapPalette();
+}
+
+
 EXTERN_CVAR(Float, vid_brightness)
 EXTERN_CVAR(Float, vid_contrast)
 
@@ -533,8 +544,11 @@ void FGLRenderer::CreateTonemapPalette()
 
 void FGLRenderer::ClearTonemapPalette()
 {
-	delete mTonemapPalette;
-	mTonemapPalette = nullptr;
+	if (mTonemapPalette)
+	{
+		delete mTonemapPalette;
+		mTonemapPalette = nullptr;
+	}
 }
 
 //-----------------------------------------------------------------------------
@@ -821,14 +835,16 @@ int FGLRenderer::PTM_BestColor (const uint32 *pal_in, int r, int g, int b, int f
 	const PalEntry *pal = (const PalEntry *)pal_in;
 	static double powtable[256];
 	static bool firstTime = true;
+	static float trackpowtable = 0.;
 
 	double fbestdist, fdist;
 	int bestcolor;
 
-	if (firstTime)
+	if (firstTime || trackpowtable != gl_paltonemap_powtable)
 	{
+		trackpowtable = gl_paltonemap_powtable;
 		firstTime = false;
-		for (int x = 0; x < 256; x++) powtable[x] = pow((double)x/255,1.2);
+		for (int x = 0; x < 256; x++) powtable[x] = pow((double)x/255, (double)gl_paltonemap_powtable);
 	}
 
 	for (int color = first; color < num; color++)
@@ -837,9 +853,9 @@ int FGLRenderer::PTM_BestColor (const uint32 *pal_in, int r, int g, int b, int f
 		double y = powtable[abs(g-pal[color].g)];
 		double z = powtable[abs(b-pal[color].b)];
 		fdist = x + y + z;
-		if (color == first || fdist < fbestdist)
+		if (color == first || ((gl_paltonemap_reverselookup)?(fdist <= fbestdist):(fdist < fbestdist)))
 		{
-			if (fdist == 0)
+			if (fdist == 0 && !gl_paltonemap_reverselookup)
 				return color;
 
 			fbestdist = fdist;
diff --git a/wadsrc/static/language.enu b/wadsrc/static/language.enu
index ae500c152..3ed8ffa77 100644
--- a/wadsrc/static/language.enu
+++ b/wadsrc/static/language.enu
@@ -2662,6 +2662,8 @@ GLPREFMNU_LENS					= "Lens distortion effect";
 GLPREFMNU_SSAO					= "Ambient occlusion quality";
 GLPREFMNU_SSAO_PORTALS			= "Portals with AO";
 GLPREFMNU_FXAA					= "FXAA Quality";
+GLPREFMNU_PALTONEMAPORDER		= "Tonemap Palette Order";
+GLPREFMNU_PALTONEMAPPOWER		= "Tonemap Palette Exponent";
 
 // Option Values
 OPTVAL_SMART 				= "Smart";
@@ -2745,6 +2747,8 @@ OPTVAL_LOW					= "Low";
 OPTVAL_MEDIUM				= "Medium";
 OPTVAL_HIGH					= "High";
 OPTVAL_EXTREME				= "Extreme";
+OPTVAL_OBVERSEFIRST			= "Obverse";
+OPTVAL_REVERSEFIRST			= "Reverse";
 
 // QZDoom exclusive:
 
diff --git a/wadsrc/static/menudef.zz b/wadsrc/static/menudef.zz
index 599c28a2d..f683f2e0d 100644
--- a/wadsrc/static/menudef.zz
+++ b/wadsrc/static/menudef.zz
@@ -1,3 +1,9 @@
+OptionValue "LookupOrder"
+{
+	0, "$OPTVAL_OBVERSEFIRST"
+	1, "$OPTVAL_REVERSEFIRST"
+}
+
 OptionValue "SpriteclipModes"
 {
 	0, "$OPTVAL_NEVER"
@@ -249,4 +255,7 @@ OptionMenu "GLPrefOptions"
 	Option "$GLPREFMNU_SSAO",		 			gl_ssao,						"SSAOModes"
 	Slider "$GLPREFMNU_SSAO_PORTALS",			gl_ssao_portals,				0.0, 4.0, 1.0, 0
 	Option "$GLPREFMNU_FXAA",		 			gl_fxaa,						"FXAAQuality"
+	StaticText " "
+	Slider "$GLPREFMNU_PALTONEMAPPOWER",		gl_paltonemap_powtable,			0.2, 3.0, 0.1, 0
+	Option "$GLPREFMNU_PALTONEMAPORDER",		gl_paltonemap_reverselookup,	"LookupOrder"
 }