Wow this is a challenge. I have an image with black cashmere, both under strobe and bright overcast natural light. Film is Portra 400 in 120. Color balance is good but the texture has me perplexed. Granted, focus is on the subject's face/eyes, and aperture was f/8 (medium format 180mm lens). I am not expecting the wardrobe to be critically sharp throughout, but I am not sure what to strive for regarding texture. Framing is both head/shoulders and full length.

Is there an approach, philosophy or technique to rendering black fabrics? Thanks!

Separate question, but similar idea - how to manage white (men's) dress shirts? What are the best resources for this?