Why aren't my gravity readings correct?

I recently purchased a refractometer and have been anxious to test it out. I brewed up a batch of beer recently and used both my hydrometer and refractometer to take a reading. I have gone through calibration of the refractometer with distilled water but my gravity readings are significantly different.

For instance, using my hydrometer my final gravity is 1.012 and using my refractometer it's 1.023. I'm not sure which is correct. Any advice to a newbie with a shiny new toy?

The ethanol is screwing up the FG reading. There is a correction calculation that needs to be applied. Try doing a google search for it.