diff --git a/CHANGELOG.md b/CHANGELOG.md
index ef1fb97f..03470110 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -98,11 +98,23 @@
 
 ## 1.1.2 (Unreleased)
 
+### Improvements
+
+* Added deletion of `*.pyc` files to `python setup.py clean` command, should help tremendously when switching branches (backported
+  from [9e014eb](https://github.com/foosel/OctoPrint/commit/9e014eba1feffde11ed0601d9c911b8cac9f3fb0))
+
 ### Bug Fixes
 
 * [#634](https://github.com/foosel/OctoPrint/pull/634) - Fixed missing `branch` fields in version dicts generated
   by versioneer
 * [IRC] Don't hiccup on slic3r filament_diameter comments generated for multi extruder setups
+* Small fixes for timelapse creation:
+  - [#344](https://github.com/foosel/OctoPrint/issues/344) - Made timelapses capable of coping with missing captures in between by decrementing the image counter again if there
+    was an error fetching the latest image from the snapshot URL (backport of [1a7a468](https://github.com/foosel/OctoPrint/commit/1a7a468eb65fdf2a13b4c7a7723280e822c9c34b)
+    and [bf9d5ef](https://github.com/foosel/OctoPrint/commit/bf9d5efe43a1e57aacd8512125082ddca06b4efc))
+  - [#693](https://github.com/foosel/OctoPrint/issues/693) -  Try not to capture an image if image counter is still unset
+  - [unreported] Synchronize image counter decrementing as well as incrementing to prevent rare race conditions when generating the
+    image file names
 
 ## 1.1.1 (2014-10-27)
 
diff --git a/setup.py b/setup.py
index 26876883..22db85f6 100644
--- a/setup.py
+++ b/setup.py
@@ -96,6 +96,26 @@ class CleanCommand(Command):
 			file_handler=delete_file
 		)
 
+		# pyc files
+		def delete_folder_if_empty(path, applied_handler):
+			if not applied_handler:
+				return
+			if len(os.listdir(path)) == 0:
+				shutil.rmtree(path)
+				print "Deleted %s since it was empty" % path
+
+		def delete_file(path):
+			os.remove(path)
+			print "Deleted %s" % path
+
+		import fnmatch
+		_recursively_handle_files(
+			os.path.abspath("src"),
+			lambda name: fnmatch.fnmatch(name.lower(), "*.pyc"),
+			folder_handler=delete_folder_if_empty,
+			file_handler=delete_file
+		)
+
 
 class NewTranslation(Command):
 	description = "create a new translation"
diff --git a/src/octoprint/timelapse.py b/src/octoprint/timelapse.py
index d737ed84..24d1dfce 100644
--- a/src/octoprint/timelapse.py
+++ b/src/octoprint/timelapse.py
@@ -227,8 +227,12 @@ class Timelapse(object):
 			self._logger.warn("Cannot capture image, capture directory is unset")
 			return
 
+		if self._imageNumber is None:
+			self._logger.warn("Cannot capture image, image number is unset")
+			return
+
 		with self._captureMutex:
-			filename = os.path.join(self._captureDir, "tmp_%05d.jpg" % (self._imageNumber))
+			filename = os.path.join(self._captureDir, "tmp_%05d.jpg" % self._imageNumber)
 			self._imageNumber += 1
 		self._logger.debug("Capturing image to %s" % filename)
 		captureThread = threading.Thread(target=self._captureWorker, kwargs={"filename": filename})
@@ -243,8 +247,9 @@ class Timelapse(object):
 			self._logger.debug("Image %s captured from %s" % (filename, self._snapshotUrl))
 		except:
 			self._logger.exception("Could not capture image %s from %s, decreasing image counter again" % (filename, self._snapshotUrl))
-			if self._imageNumber is not None and self._imageNumber > 0:
-				self._imageNumber -= 1
+			with self._captureMutex:
+				if self._imageNumber is not None and self._imageNumber > 0:
+					self._imageNumber -= 1
 		eventManager().fire(Events.CAPTURE_DONE, {"file": filename})
 
 	def _createMovie(self, success=True):