[ambrotype] Man in striped vest with the scarf

How do you get such razor sharpness in your subjects' faces, when the exposures are routinely over 5 or 6 seconds?

Do you use a brace of some type? Or some type of studio lighting as opposed to available light? I'm curious, because your images are consistent that way.

This is a wonderful plate, your soup on this is perfect Alex

I'm in awe of these plates!! Wow.

Thank you for comments and kind words!
Colin, for this portrait I use continues artificial light and I use head rest for sure.