diff --git a/src/shearwater_predator_parser.c b/src/shearwater_predator_parser.c
index 6c2ac18..57a6487 100644
--- a/src/shearwater_predator_parser.c
+++ b/src/shearwater_predator_parser.c
@@ -694,7 +694,7 @@ shearwater_predator_parser_get_field (dc_parser_t *abstract, dc_field_type_t typ
 			break;
 		case DC_FIELD_ATMOSPHERIC:
 			idx = parser->pnf ? parser->block_offset[LOG_RECORD_OPENING_1] + 16 : 47;
-			*((double *) value) = array_uint16_be (data + 47) / 1000.0;
+			*((double *) value) = array_uint16_be (data + idx) / 1000.0;
 			break;
 		case DC_FIELD_DIVEMODE:
 			*((dc_divemode_t *) value) = parser->mode;