diff --git a/src/cam.c b/src/cam.c
index 5ce6a93..ea946d2 100644
--- a/src/cam.c
+++ b/src/cam.c
@@ -335,19 +335,19 @@ static int mk_cam(uint8_t *cam_oer, uint32_t *cam_len) {
                 ph->list.array[0] = calloc(1,sizeof(PathPoint_t));
 
                 if (lightship->path_history[0]->alt != AltitudeValue_unavailable && pn.alt != AltitudeValue_unavailable) {
-                    ph->list.array[0]->pathPosition.deltaAltitude = pn.alt - lightship->path_history[0]->alt;
+                    ph->list.array[0]->pathPosition.deltaAltitude = lightship->path_history[0]->alt - pn.alt;
                 } else {
                     ph->list.array[0]->pathPosition.deltaAltitude = DeltaAltitude_unavailable;
                 }
 
                 if (lightship->path_history[0]->lat != Latitude_unavailable && pn.lat != Latitude_unavailable) {
-                    ph->list.array[0]->pathPosition.deltaLatitude = pn.lat - lightship->path_history[0]->lat;
+                    ph->list.array[0]->pathPosition.deltaLatitude = lightship->path_history[0]->lat - pn.lat;
                 } else {
                     ph->list.array[0]->pathPosition.deltaLatitude = DeltaLatitude_unavailable;
                 }
 
                 if (lightship->path_history[0]->lon != Longitude_unavailable && pn.lon != Longitude_unavailable) {
-                    ph->list.array[0]->pathPosition.deltaLongitude = pn.lon - lightship->path_history[0]->lon;
+                    ph->list.array[0]->pathPosition.deltaLongitude = lightship->path_history[0]->lon - pn.lon;
                 } else {
                     ph->list.array[0]->pathPosition.deltaLongitude = DeltaLongitude_unavailable;
                 }
diff --git a/src/requests.c b/src/requests.c
index dcebdd2..0be350d 100644
--- a/src/requests.c
+++ b/src/requests.c
@@ -175,19 +175,19 @@ int facilities_request_single_message(void* responder, FacilitiesMessageRequest_
 
                     itss_space_lock();
                     if (path_history[0]->alt != AltitudeValue_unavailable && epv.space.altitude != AltitudeValue_unavailable) {
-                        ph->list.array[0]->pathPosition.deltaAltitude = epv.space.altitude - path_history[0]->alt;
+                        ph->list.array[0]->pathPosition.deltaAltitude = path_history[0]->alt - epv.space.altitude;
                     } else {
                         ph->list.array[0]->pathPosition.deltaAltitude = DeltaAltitude_unavailable;
                     }
 
                     if (path_history[0]->lat != Latitude_unavailable && epv.space.latitude != Latitude_unavailable) {
-                        ph->list.array[0]->pathPosition.deltaLatitude = epv.space.latitude - path_history[0]->lat;
+                        ph->list.array[0]->pathPosition.deltaLatitude = path_history[0]->lat - epv.space.latitude;
                     } else {
                         ph->list.array[0]->pathPosition.deltaLatitude = DeltaLatitude_unavailable;
                     }
 
                     if (path_history[0]->lon != Longitude_unavailable && epv.space.longitude != Longitude_unavailable) {
-                        ph->list.array[0]->pathPosition.deltaLongitude = epv.space.longitude - path_history[0]->lon;
+                        ph->list.array[0]->pathPosition.deltaLongitude =path_history[0]->lon - epv.space.longitude;
                     } else {
                         ph->list.array[0]->pathPosition.deltaLongitude = DeltaLongitude_unavailable;
                     }