the magic of the Sherlock stories isn't that you can figure them out by the clues Doyle leaves (which are few)
it's that the story is presented from a third party who DOESN'T notice the details until Sherlock tells him what they are.

The majority of the stories begin with Sherlock being introduced to a character and then Sherlock telling us everything we could possibly know about this character without us being able to deduce any of it ourself.

This is played out perfectly in the film,
specifically in his first meetings with Mary and Sir Thomas.

Although we can see Mary and what she is wearing,
Ritchie does not give us a close up of her necklace, ring, etc.

Instead he lets Sherlock do the noticing and the audience the enjoying.

As an enormous Sherlock fan I must admit that the things that happen in his stories annoy me in every other mystery (if I can't figure it out it's bullshit!) but I love it when Sherlock does it.