diff --git a/exif.py b/exif.py
index 22993e5..356685d 100644
--- a/exif.py
+++ b/exif.py
@@ -1,85 +1,107 @@
 import json
+import logging
+from datetime import datetime
 
-import PIL.ExifTags
+import pytz
 from PIL import Image, IptcImagePlugin, TiffImagePlugin
 
+logger = logging.getLogger(__name__)
+
+
+""" Required exif values """
+TAGS_EXIF = {
+    0x9003: "DateTimeOriginal",
+    0x829D: "FNumber",
+    0x829A: "ExposureTime",
+    0x8827: "ISOSpeedRatings",
+    0x9204: "ExposureBiasValue",
+    0x8822: "ExposureProgram",
+    0x9207: "MeteringMode",
+    0x920A: "FocalLength",
+    0xA405: "FocalLengthIn35mmFilm",
+    0x0110: "Model",
+    0xA434: "LensModel",
+}
+
+""" Required iptc values """
+TAGS_IPTC = {
+    (2, 25): "Keywords",
+    (2, 55): "DateCreated",
+    (2, 60): "TimeCreated",
+}
+
 
 class Exif:
 
     def __init__(self, filename: str):
+
         self.filename = filename
-        self.exif = {}
+        self._exif = {}
+        self._iptc = {}
+        self.data = {}
+
+        """ Open image file """
         try:
-            self.img = Image.open(self.filename)
-            self.img.verify() 
-            self._readExif()
-            self._readIptc()
-        except:
-            print("Error Couldn't open image: %s" % filename)
+            with Image.open(self.filename) as self.img:
+                self.img.verify()
+        except Exception:
+            logger.exception('Could not open image: %s', self.filename)
 
-
-    def _readExif(self):
-        img = self.img._getexif()
-        for (key, value) in img.items():
-            if key in PIL.ExifTags.TAGS:
+        """ Read exif tags """
+        try:
+            self._exif = {
+                TAGS_EXIF[k]: v
+                for k, v in self.img._getexif().items()
+                if k in TAGS_EXIF
+            }
+            for (key, value) in self._exif.items():
                 if isinstance(value, TiffImagePlugin.IFDRational):
-                    value = float(value)
+                    self.data[key] = float(value)
                 elif isinstance(value, tuple):
-                    value = tuple(float(t) if isinstance(t, TiffImagePlugin.IFDRational) else t for t in value)
+                    self.data[key] = tuple(float(t) if isinstance(t, TiffImagePlugin.IFDRational) else t for t in value)
                 elif isinstance(value, bytes):
-                    value = value.decode(errors="replace")
-                self.exif[PIL.ExifTags.TAGS[key]] = value
-        return self.exif
+                    self.data[key] = value.decode('utf-8')
+                else:
+                    self.data[key] = value
+        except Exception:
+            logger.warning('Could not read exif metadata from: %s', self.filename)
 
-    def _readIptc(self):
-        iptcTAGS = {
-            (1, 90): 'CodedCharacterSet',
-            (2, 0): 'RecordVersion',
-            (2, 5): 'ObjectName',
-            (2, 25): 'Keywords',
-            (2, 55): 'DateCreated',
-            (2, 60): 'TimeCreated',
-            (2, 62): 'DigitizationDate',
-            (2, 63): 'DigitizationTime',
-            (2, 80): 'Byline',
-            (2, 120): 'Caption',
-            (2, 90): 'City',
-            (2, 92): 'Sub location',
-            (2, 95): 'Province State',
-            (2, 100): 'Country Code',
-            (2, 101): 'Country Name',   
-        }
-        img = IptcImagePlugin.getiptcinfo(self.img)
-        for (key, value) in img.items():
-            decoded = iptcTAGS.get(key, str(key))
-            if isinstance(value, list):
-                self.exif[decoded] = [x.decode('utf-8') for x in value]
-            else:
-                self.exif[decoded] = value.decode('utf-8')
-        return self.exif
+        """ Read iptc tags """
+        try:
+            self._iptc = {
+                TAGS_IPTC[k]: v
+                for k, v in IptcImagePlugin.getiptcinfo(self.img).items()
+                if k in TAGS_IPTC
+            }
+            for (key, value) in self._iptc.items():
+                if isinstance(value, list):
+                    self.data[key] = [x.decode('utf-8') for x in value]
+                else:
+                    self.data[key] = value.decode('utf-8')
+        except Exception:
+            logger.warning('Could not read iptc metadata from: %s', self.filename)
 
-    def getValue(self, value):
-        if value in self.exif.keys():
-            return self.exif[value]
+    def datetimeoriginal(self, timezone='UTC'):
+        """ Return DateTimeOriginal with timezone """
+        if 'DateTimeOriginal' in self.data:
+            try:
+                return datetime.strptime(self.data['DateTimeOriginal'], "%Y:%m:%d %H:%M:%S").astimezone(pytz.timezone(timezone))
+            except ValueError as e:
+                logger.warning('Could not parse date from: %s', self.filename)
         else:
-            return {}
+            return datetime.now(pytz.timezone(timezone))
 
-    def getJson(self):
-        return json.dumps(self.exif)
+    def json(self):
+        """ Return exif data in json format """
+        return json.dumps(self.data)
+
+    def keywords(self):
+        """ Return Keywords list """
+        if 'Keywords' not in self.data:
+            return []
+        if type(self.data['Keywords']) == list:
+            return self.data['Keywords']
+        return [self.data['Keywords']]
 
-    def getDic(self):
-        return self.exif
-    
     def __str__(self):
         return self.filename
-
-
-
-xxx = Exif('./photo.jpg')
-
-print(xxx.getJson())
-print(xxx.getValue('Keywords'))
-print(xxx.getValue('DateTimeOriginal'))
-print(xxx.getDic())
-print(xxx)
-