Mike Mitchell's previously unpublished early Beatles photos have impressed appraisers so much they anticipate the 413 negatives will fetch a top bid of close to $350,000 during a March 24 auction being conducted by Omega Auctions. The valuation is based on the rarity of high quality, candid photos of the Beatles during their first US visits. Only 46 have been shown before. The collection includes pics of the four at pre-concert press sessions and on stage at their Washington, DC and Baltimore shows. One factor that makes them more unique is that the then 18 year old photographer took all of his shots without a flash.