Converted tab indentation to spaces, for explicitness's sake.
Refactor ExIF field names and hex offsets into separate lists, and zip them together into dict.
Ripped out files list comprehension and rebuilt with map and filter. Loop through sys.argv directly, rather than looping through a range and indexing. Use os.path.join instead of string concatenation in some places.
Modified other loop to go through sys.argv directly, rather than indexing unnecessarily. Extension check now looks for upper and lowercase versions of .jpg and .jpeg.
Use dict .get() rather than indexing the dictionary, in case a key doesn't exist. Dict get() will return None if the key doesn't exist in the dict, rather than throwing a KeyError.
Added some error-checking. If no exif data exists in image, detect that 'data' is None and make it an empty dict. Make sure aperature, shutterSpeed, and focalLength have empty valuesn if the exif data doesn't exist. Unpack filename and data from exif list in loop, rather than indexing each exif list entry inside of loop. After each file, print newline to ensure we move to next row in CSV (I accidentally deleted this earlier).
Changed all double quotes to single. Because.
Wrapped results_file.write(value + ',') in a lambda, so we don't have to look at the plus-comma a million times. Also, I like lambdas.
Merge pull request #1 from euphwes/wes_changes

Merging wonderful changes