diff --git a/metis_l2_prep_uv.pro b/metis_l2_prep_uv.pro
index 1a55c861e219403b57a3ab784babc648a37bdfb6..b9ff6f366bf93e65b7e0c3dbbced60faef6c1303 100644
--- a/metis_l2_prep_uv.pro
+++ b/metis_l2_prep_uv.pro
@@ -155,7 +155,7 @@ pro metis_l2_prep_uv
 	; fix planning info keywords
 
 	if header.soopname.startswith('unknown') then soopname = 'none' else soopname = header.soopname
-	if header.obs_mode.startswith('unknown') then obs_mode = 'none' else obs_mode = header.obs_mode
+	if header.obs_mode.startswith('unknown') then obs_mode = 'METIS_GENERIC_OBS' else obs_mode = header.obs_mode
 	if soopname eq 'none' then sooptype = 'none' else sooptype = header.sooptype
 	if obs_mode eq 'none' then obs_type = 'none' else obs_type = header.obs_type
 	if soopname eq 'none' and obs_mode eq 'none' then obs_id = 'none' else obs_id = header.obs_id
diff --git a/metis_l2_prep_vl_generic.pro b/metis_l2_prep_vl_generic.pro
index 810e0058df8f176e80de0bfa981d1c4ab3868500..27ccaaa17ff09716bf8a0bc6ff2d63223facc1c8 100644
--- a/metis_l2_prep_vl_generic.pro
+++ b/metis_l2_prep_vl_generic.pro
@@ -174,7 +174,7 @@ pro metis_l2_prep_vl_generic
 	; fix planning info keywords
 
 	if header.soopname.startswith('unknown') then soopname = 'none' else soopname = header.soopname
-	if header.obs_mode.startswith('unknown') then obs_mode = 'none' else obs_mode = header.obs_mode
+	if header.obs_mode.startswith('unknown') then obs_mode = 'METIS_GENERIC_OBS' else obs_mode = header.obs_mode
 	if soopname eq 'none' then sooptype = 'none' else sooptype = header.sooptype
 	if obs_mode eq 'none' then obs_type = 'none' else obs_type = header.obs_type
 	if soopname eq 'none' and obs_mode eq 'none' then obs_id = 'none' else obs_id = header.obs_id
diff --git a/metis_l2_prep_vl_polariz.pro b/metis_l2_prep_vl_polariz.pro
index c6d39d39f0909366576d5f71afed21a0642baab6..4c7108c00d593878f5b1bda407cf4fdb6d041f1f 100755
--- a/metis_l2_prep_vl_polariz.pro
+++ b/metis_l2_prep_vl_polariz.pro
@@ -353,7 +353,7 @@ pro metis_l2_prep_vl_polariz
 	; fix planning info keywords
 
 	if header.soopname.startswith('unknown') then soopname = 'none' else soopname = header.soopname
-	if header.obs_mode.startswith('unknown') then obs_mode = 'none' else obs_mode = header.obs_mode
+	if header.obs_mode.startswith('unknown') then obs_mode = 'METIS_GENERIC_OBS' else obs_mode = header.obs_mode
 	if soopname eq 'none' then sooptype = 'none' else sooptype = header.sooptype
 	if obs_mode eq 'none' then obs_type = 'none' else obs_type = header.obs_type
 	if soopname eq 'none' and obs_mode eq 'none' then obs_id = 'none' else obs_id = header.obs_id