--- a/www/getispindellog.php	Sat Aug 19 15:11:35 2023 +0200
+++ b/www/getispindellog.php	Wed Aug 23 10:30:09 2023 +0200
@@ -13,15 +13,25 @@
 }
 mysqli_set_charset($connect, "utf8" );
 
+function HydroCorrection($mg, $tr, $tc)
+{
+    $trf = $tr * 1.8 + 32;
+    $tcf = $tc * 1.8 + 32;
+
+    return $mg * ((1.00130346 - 1.34722124E-4 * $trf + 2.04052596E-6 * $trf * $trf - 2.32820948E-9 * $trf * $trf * $trf) /
+                  (1.00130346 - 1.34722124E-4 * $tcf + 2.04052596E-6 * $tcf * $tcf - 2.32820948E-9 * $tcf * $tcf * $tcf));
+}
+
 $query = "SELECT * FROM log_ispindel WHERE code='".$code."' ORDER BY datetime;";
 $result = mysqli_query($connect, $query) or die("SQL Error 1: " . mysqli_error($connect));
 while ($row = mysqli_fetch_array($result, MYSQLI_ASSOC)) {
 
+    $SG = HydroCorrection($row['sg'], $row['temperature'], 20.0);
     $logs[] = array(
 	'date' => substr($row['datetime'],0,16),
 	'temperature' => $row['temperature'],
 	'plato' => $row['plato'],
-	'sg' => $row['sg'],
+	'sg' => $SG,
 	'battery' => $row['battery']
     );
 }