diff --git a/src/p_setup.c b/src/p_setup.c
index 5d7fd3179..cc5ee3cc8 100644
--- a/src/p_setup.c
+++ b/src/p_setup.c
@@ -1469,7 +1469,7 @@ static void P_LoadRawSideDefs2(void *data)
 			case 447: // Change colormap of tagged sectors! -- Monster Iestyn 14/06/18
 				// SoM: R_CreateColormap will only create a colormap in software mode...
 				// Perhaps we should just call it instead of doing the calculations here.
-				sec->extra_colormap = sec->spawn_extra_colormap = R_CreateColormap(msd->toptexture, msd->midtexture,
+				sd->colormap_data = R_CreateColormap(msd->toptexture, msd->midtexture,
 					msd->bottomtexture);
 				sd->toptexture = sd->midtexture = sd->bottomtexture = 0;
 				break;
diff --git a/src/p_spec.c b/src/p_spec.c
index fd02803cc..cc4dfb9e1 100644
--- a/src/p_spec.c
+++ b/src/p_spec.c
@@ -3260,8 +3260,9 @@ static void P_ProcessLineSpecial(line_t *line, mobj_t *mo, sector_t *callsec)
 				if (line->flags & ML_EFFECT3) // relative calc
 				{
 					extracolormap_t *exc = R_AddColormaps(
-						(line->flags & ML_TFERLINE) ? line->backsector->extra_colormap : sectors[secnum].extra_colormap, // use back colormap instead of target sector
-						line->frontsector->extra_colormap,
+						(line->flags & ML_TFERLINE) && line->sidenum[1] != 0xFFFF ?
+							sides[line->sidenum[1]].colormap_data : sectors[secnum].extra_colormap, // use back colormap instead of target sector
+						sides[line->sidenum[0]].colormap_data,
 						line->flags & ML_EFFECT1,  // subtract R
 						line->flags & ML_NOCLIMB,  // subtract G
 						line->flags & ML_EFFECT2,  // subtract B
@@ -3289,7 +3290,7 @@ static void P_ProcessLineSpecial(line_t *line, mobj_t *mo, sector_t *callsec)
 				}
 				else if (line->flags & ML_DONTPEGBOTTOM) // alternate alpha (by texture offsets)
 				{
-					extracolormap_t *exc = R_CopyColormap(line->frontsector->extra_colormap, false);
+					extracolormap_t *exc = R_CopyColormap(sides[line->sidenum[0]].colormap_data, false);
 					exc->rgba = R_GetRgbaRGB(exc->rgba) + R_PutRgbaA(max(min(sides[line->sidenum[0]].textureoffset >> FRACBITS, 25), 0));
 					exc->fadergba = R_GetRgbaRGB(exc->fadergba) + R_PutRgbaA(max(min(sides[line->sidenum[0]].rowoffset >> FRACBITS, 25), 0));
 
@@ -3303,7 +3304,7 @@ static void P_ProcessLineSpecial(line_t *line, mobj_t *mo, sector_t *callsec)
 						Z_Free(exc);
 				}
 				else
-					sectors[secnum].extra_colormap = line->frontsector->extra_colormap;
+					sectors[secnum].extra_colormap = sides[line->sidenum[0]].colormap_data;
 			}
 			break;
 
@@ -6817,7 +6818,7 @@ void P_SpawnSpecials(INT32 fromnetsave)
 
 			case 606: // HACK! Copy colormaps. Just plain colormaps.
 				for (s = -1; (s = P_FindSectorFromLineTag(lines + i, s)) >= 0 ;)
-					sectors[s].extra_colormap = sectors[s].spawn_extra_colormap = lines[i].frontsector->extra_colormap;
+					sectors[s].extra_colormap = sectors[s].spawn_extra_colormap = sides[lines[i].sidenum[0]].colormap_data;
 				break;
 
 #ifdef ESLOPE // Slope copy specials. Handled here for sanity.
diff --git a/src/r_defs.h b/src/r_defs.h
index 63ca29aa1..1f2afdb99 100644
--- a/src/r_defs.h
+++ b/src/r_defs.h
@@ -476,6 +476,8 @@ typedef struct
 	INT16 repeatcnt; // # of times to repeat midtexture
 
 	char *text; // a concatination of all top, bottom, and mid texture names, for linedef specials that require a string.
+
+	extracolormap_t *colormap_data; // storage for colormaps; not applied to sectors.
 } side_t;
 
 //