diff --git a/metis_l1_prep.pro b/metis_l1_prep.pro
index 3742f4915f226710d3ad4e2b0b548778f94a27a3..24718b42f6f9935b50b442c9c6d448a8dc7ef319 100755
--- a/metis_l1_prep.pro
+++ b/metis_l1_prep.pro
@@ -182,6 +182,7 @@ pro metis_l1_prep
 	; rebin the image if binning was applied during the acquisition and check for the data quality
 	; NOTE - this is done only for image data products
 
+	comment = !null
 	if datatype le 6 then begin
 		bin_type = fxpar(primary_header, 'B0_BIN', missing = 0)
 
@@ -290,13 +291,13 @@ pro metis_l1_prep
 	fxaddpar, primary_header, 'OBS_TYPE', obs_type, 'Encoded version of OBS_MODE', before = 'DATAMIN'
 	fxaddpar, primary_header, 'FILTER', filter, 'Filter used to acquire this image', before = 'DATAMIN'
 	fxaddpar, primary_header, 'WAVELNTH', wavelnth, '[nm] Characteristic wavelength of observation', before = 'DATAMIN'
-	fxaddpar, primary_header, 'WAVEMIN', wavemin, '[nm] Min. wavelength where response > 0.05 of max.', before = 'DATAMIN'
-	fxaddpar, primary_header, 'WAVEMAX', wavemax, '[nm] Max. wavelength where response > 0.05 of max.', before = 'DATAMIN'
+	fxaddpar, primary_header, 'WAVEMIN', wavemin, '[nm] Min. bandpass wavelength', before = 'DATAMIN'
+	fxaddpar, primary_header, 'WAVEMAX', wavemax, '[nm] Max. bandpass wavelength', before = 'DATAMIN'
 	fxaddpar, primary_header, 'WAVEBAND', waveband, 'Bandpass description', before = 'DATAMIN'
 	fxaddpar, primary_header, 'XPOSURE', xposure, '[s] Total effective exposure time', before = 'DATAMIN'
 	fxaddpar, primary_header, 'NSUMEXP', nsumexp, 'Number of detector readouts summed together', before = 'DATAMIN'
-	fxaddpar, primary_header, 'TELAPSE', telapse, '[s] Elapsed time between beginning and end of observation', before = 'DATAMIN'
-	fxaddpar, primary_header, 'SOOPNAME', planning_data.soop_name, 'Name of the SOOP campaign that the data belong to', before = 'DATAMIN'
+	fxaddpar, primary_header, 'TELAPSE', telapse, '[s] Elapsed time during observation', before = 'DATAMIN'
+	fxaddpar, primary_header, 'SOOPNAME', planning_data.soop_name, 'Name of the SOOP that the data belong to', before = 'DATAMIN'
 	fxaddpar, primary_header, 'SOOPTYPE', soop_type, 'Campaign ID(s) that the data belong to', before = 'DATAMIN'
 	fxaddpar, primary_header, 'OBS_ID', planning_data.obs_id, 'Unique ID of the individual observation', before = 'DATAMIN'
 	fxaddpar, primary_header, 'TARGET', 'TBD', 'Type of target from planning', before = 'DATAMIN'
@@ -308,16 +309,16 @@ pro metis_l1_prep
 	fxaddpar, primary_header, 'DATAMIN', min(data, /nan)
 	fxaddpar, primary_header, 'DATAMAX', max(data, /nan)
 	fxaddpar, primary_header, 'IDB_VERS', input.idb_version, '', before = 'HDR_VERS'
-	fxaddpar, primary_header, 'INFO_URL', 'http://metis.oato.inaf.it', 'Link to more information on the instrument data', before = 'HISTORY'
+	fxaddpar, primary_header, 'INFO_URL', 'http://metis.oato.inaf.it', 'Link to more information on the instrument', before = 'HISTORY'
 
 	if datatype le 6 then begin
 		fxaddpar, primary_header, 'NBIN1', bin_fact, 'Binning factor in the dimension 1', before = 'COMPRESS'
 		fxaddpar, primary_header, 'NBIN2', bin_fact, 'Binning factor in the dimension 2', before = 'COMPRESS'
 		fxaddpar, primary_header, 'NBIN', bin_fact * bin_fact, 'Product of all NBIN values above', before = 'COMPRESS'
-		fxaddpar, primary_header, 'PXBEG1', 1, 'First pixel that has been read out in dimension 1', before = 'COMPRESS'
-		fxaddpar, primary_header, 'PXBEG2', 1, 'First pixel that has been read out in dimension 2', before = 'COMPRESS'
-		fxaddpar, primary_header, 'PXEND1', naxis1, 'Last pixel that has been read out in dimension 1', before = 'COMPRESS'
-		fxaddpar, primary_header, 'PXEND2', naxis2, 'Last pixel that has been read out in dimension 2', before = 'COMPRESS'
+		fxaddpar, primary_header, 'PXBEG1', 1, 'First pixel read out in dimension 1', before = 'COMPRESS'
+		fxaddpar, primary_header, 'PXBEG2', 1, 'First pixel read out in dimension 2', before = 'COMPRESS'
+		fxaddpar, primary_header, 'PXEND1', naxis1, 'Last pixel read out in dimension 1', before = 'COMPRESS'
+		fxaddpar, primary_header, 'PXEND2', naxis2, 'Last pixel read out in dimension 2', before = 'COMPRESS'
 	endif
 
 	; read the house-keeping telemetry
diff --git a/metis_wcs.pro b/metis_wcs.pro
index 85c0ec179d41010bc977e36fb10715b8729261ef..1a4b6564d8b7196242fcca1c699200d90b820f6e 100644
--- a/metis_wcs.pro
+++ b/metis_wcs.pro
@@ -204,19 +204,19 @@ function metis_wcs, header, cal_pack, ref_detector = ref_detector
 	wcs.add, { $
 		name: 'FS_XCEN', $
 		value: crpix[0], $
-		comment: '[pixel] Metis field-stop center location along axis 1'}
+		comment: '[pixel] Metis FS center location along axis 1'}
 	wcs.add, { $
 		name: 'FS_YCEN', $
 		value: crpix[1], $
-		comment: '[pixel] Metis field-stop center location along axis 2'}
+		comment: '[pixel] Metis FS center location along axis 2'}
 	wcs.add, { $
 		name: 'FSPIX1', $
 		value: crpix[0], $
-		comment: '[pixel] Metis field-stop center location along axis 1'}
+		comment: '[pixel] Metis FS center location along axis 1'}
 	wcs.add, { $
 		name: 'FSPIX2', $
 		value: crpix[1], $
-		comment: '[pixel] Metis field-stop center location along axis 2'}
+		comment: '[pixel] Metis FS center location along axis 2'}
 	wcs.add, { $
 		name: 'SC_XCEN', $
 		value: pntpix[0], $
diff --git a/solo_get_ephemeris.pro b/solo_get_ephemeris.pro
index 58a18f6e598ca65430e3e77ab1d6e2f17ab1a86b..061cce0f7976ba798909095b81eec476f4f05d77 100644
--- a/solo_get_ephemeris.pro
+++ b/solo_get_ephemeris.pro
@@ -227,11 +227,11 @@ function solo_get_ephemeris, header, cal_pack
 	ephemerides.add, { $
 		name: 'DATE_EAR', $
 		value: date_ear, $
-		comment: '[UTC] Start time of observation, corrected to Earth'}
+		comment: '[UTC] Obs. start time corrected to Earth'}
 	ephemerides.add, { $
 		name: 'DATE_SUN', $
 		value: date_sun, $
-		comment: '[UTC] Start time of observation, corrected to Sun'}
+		comment: '[UTC] Obs. start time corrected to Sun'}
 
 	return, ephemerides
 end