Madonna and This is almost a nursing-photo and I believe that the lighting was purposely dimmed. In my first daguerreotype board there are two nursing-photos. They were not considered improper, nor immodest.
1/6 plate daguerreotype - stunning dag of two young ladies - amazing fashions
[daguerreotype portrait of a elderly woman holding spectacles with a young girl who appears to be cross-eyed] via the Historical Society of Pennsylvania, Cased Photographs Collection