The picture in question was taken in 1868, one of a series of photos he had done at Matthew Brady's studio when he visited New York for the Democratic Convention. That particular photo has been altered many times, different uniforms put on and the hair whitened much more than it was then. I believe it was used more for various newspapers, articles, reunions and other publicity items. This is a photo done by Matthew Brady in 1868 - very different.
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