It is a real and correct Afrikaans word, but it can sound a bit more formal or literary depending on context.
In everyday speech, Afrikaans speakers might often choose a different word depending on what they mean:
So aansig is fine, but it is not always the most colloquial choice.
Because duidelik comes after the verb is and is being used as a predicate adjective.
In Afrikaans:
So:
Yes. Duidelik can mean:
For example:
So in your sentence, duidelik could refer to literal visual clarity or more general distinctness, depending on the context.