Contect will matter. 1 - "It's so Tom." could be said if there is something a bit unique or ideosyncratic about the picture of Tom, like him doing something or dressed in some way that would be very characteristic of Tom or Tom's personality. 2 - "It's Tom himself." sounds a bit awkward to me. If you're just saying the person in the picture is really Tom and not someone else then "It is Tom." is all that is needed. 3 - That works, but small typo -- winner not winer. I think words that end in a single consonant will typically repeat the consonant before adding the "er" ending. (see https://www.yourdictionary.com/articles/suffix-spelling-rules if interested)