Photo and Drawing - Done at the Same Time?

I came across the above amazing photograph a while back. It captures a moment in the Civil War, that in my humble opinion, we see too little, but obviously was not uncommon. An African American family, or possibly extended family, or perhaps it's even two families, is shown with a wagon drawn by two horses or mules while Union cavalrymen or officers stand nearby.  The photograph shows at least 15 people in the traveling group. Those 15 people were likely someone's property shortly before this photograph was taken. Some of the individuals have Union army caps and coats that they probably picked along their way. They apparently stopped in Union lines long enough to have a photographer record this moment.

A multitude of questions come to my mind when I see images like this. What are their names? Where did they come from? Where did they want to go? Did their owners abandon them to avoid the Union army (thus their having horses/mules and wagon), or did they runaway and take their conveyance? Are they happy or apprehensive about the future?  Maybe both. Have they had enough to eat? Are they keeping warm? How were they treated in slavery? Did they leave any family members behind? Did they have to avoid slave patrols? So many questions.....

After finding the above drawing another question came to mind. Was the drawing done at the same time the photograph was taken? There are some subtle differences between the two, but there is too much in common in both images to not be depicting the same scene.

The drawing was made by famous Civil War correspondent artist Alfred Waud. Waud's numerous works are easily recognizable to Civil War students for their detail and realism. But, here, Waud wasn't standing next to the photographer when he sketched this one.

Information provided by the Library of Congress explains that Waud made his sketch on January 1, 1863, the day the Emancipation Proclamation went into effect, from the photograph. Waud titled the sketch "An arrival in Camp--under the Proclamation of Emancipation," and it was published in Harper's Weekly magazine on January 31, 1863.

Images courtesy of the Library of Congress