Vermeer painted sharp details in his areas of light. And much less detail is found in his shadows. Also, your reference photos clearly show this.
This manipulation of detail is especially effective when the contrast between light and shadow is as dramatic as in this painting.
I think that if you soften the details in the shadow side of her face and hair, you will be taking a giant step toward "realism" - and I am sure that if Vermeer were still alive he would be proud of your first effort John.
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