Thanks for that, definite food for thought. There still appears to be a slight elevation in the background but not nearly as much as in the original photo, while the dead appear to be on a steep slope. According to Frassanito the camera was moved around 135 degrees to take some of the other photos, does your leveling method work on them too?
Edited to add quoted material from "Gettysburg, A Journey in Time", William A. Frassanito, Scribners, 1975, pp. 222 & 224:
" For the majority of the almost sixty Gettysburg titles listed in that publication, Gardner did make an honest effort to describe the views' locations to the best of his knowledge (understandably limited). Typical of his identifications were 'View in Slaughter Pen, foot of Round Tom' (V-17), 'Scene in a wheatfield on the Confederate right'... Gardner, for the most part, was not attempting to fool anyone.
" But of all the titles listed in the 1863 catalogue, one--and only one--stands out as odd. Identified as a 'View in the field on the right wing where General Reynolds fell,' this photograph (13b), an eight-by-ten-inch plate showing several dead soldiers, was the only view in Gardner's entire Gettysburg series to be captioned in the 1863 catalogue as a scene taken on the first day's field.
" Two stereo versions of the identical view also appear in the catalogue. But significantly enough, their identifications made no mention of General Reynolds. The stereo captions read simply 'View in field on right wing' (13a) and 'Federal soldiers as they fell.'
" Additionally, a pair of companion photographs, though not identified as such, were recorded of these same bodies from a completely different camera position and at an angle of roughly 135 degrees clockwise from the other three views. [That the bodies were identical is demonstrated--for the first time--by the diagram on page 223.] The first of the two companion scenes was an eight-by-ten-inch plate entitled 'A Harvest of Death' (14). The second, identical to the first except in stereo form, was listed as 'Evidence of how severe the contest had been on the right.' Again, no mention was made of General Reynolds."