Help, Advice and C&C for Portrait Novice

While I have of course taken portraits, people shots, in the three years I have been pursuing this hobby, I am uncomfortable and awkward when doing them, much the same as having my photo taken in fact.    Always find myself rushing, not thinking enough.  I understand that a good portrait should capture something of the person as well as being a good exposure.

My first grandchild is due early next year and I hope to get over this problem before then.

I am more comfortable with natural light than flash but because of constantly rushing never use it to its best effect, reflectors etc.

Anyhow, today was my Dad's 88th birthday and I took a few shots.  This one here is the one I felt captured "My Dad" to me.   I actually shot this Mono and I love how my Dad's silver hair looks.   C&C please and any advice on how to improve.



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Jayboo