Based on what I can find on this HDR photo process this image ("Machinery") was done using  Photomatrix Pro by photographer Heiwa4126...his photostream can be viewed on Flickr…here  (this particular image can be found on page 22). Acccording to this web site the artist used three exposures:  -2EV, 0EV,+2EV. Photomatrix Pro is a stand-alone software package but it distributes a free software trial and a Photoshop plugin trial for CS2, CS3, CS4 which can be gotten at the bottom  here.