Over the years, other daguerreotypes and pictures have been brought forward and purported to be Emily Dickinson. One of the most famous is that purchased by Herman Abromson from a Greenwich Village bookseller. Richard Sewall featured this image as a frontispiece for Volume 2 of The Life of Emily Dickinson (1974) and in 1993, Joe Nickell published this article in the EDIS Bulletin showing why he thinks the image is not Emily Dickinson.

Article by Nickell.
Joe Nickell, "A Likeness of Emily?" EDIS Bulletin 5.2 (Nov/Dec 1993): 1-3, 15

Also, in 2009, George Gleason published an article in the Emily Dickinson Journal 18.2 (2009) showing why he thinks that University of North Carolina Professor Philip Gura's discovery of a daguerreotype that he released in 2000 is not Emily Dickinson. Gura's story on the daguerreotype can be found at http://www.unc.edu/~gura/dickinson/index.html.