Was Wittgenstein's picture theory of meaning/language, as posited in the Tractatus, and which was closely aligned with his analytic realism/logical atomism, simply an elucidation and elaboration of the traditional correspondence theory? How so? If not, what was interestingly novel about it. How are the two theories best distinguished from one another?
According to the correspondence principle, a statement is true if it accurately describes reality. What Wittgenstein wants to know is how exactly (and whether) our minds can accomplish that feat. His question is "How can we accurately describe the reality?". And he offers his picture theory as a possible answer.
Of course, in order to explain how we describe reality, we need to know what reality is in the first place? -- so Wittgenstein offers his answer to that question as well.
And it's close -- but no cigar. The correspondence is, yes, visual in nature, but it is not between 2-D pictures and reality. The real world has three space dimensions plus time -- that's why it takes a full-blown 3-D simulation to adequately represent a particular aspect of reality -- go ahead and call it a "mental model". Both assembling and, later, running it inside one's head is, basically, a form of daydreaming.
It takes a bit a Googling (plus some healthy imagination and just enough courage to keep an open mind) to connect the dots and piece together individual models till you have the rest of it covered -- a comprehensive 3-D simulation of reality. Which, sadly, no modern language has a word for. But that's what Sanskrit's "ātman", or Greek's "lógos" (as in "the lógos became flesh" or in Heraclitus' fragments) used to mean1 -- a deep understanding of ourselves, our lives, and the world around.
And yes, you can do it too -- everyone can!
1 ... and, technically, so "used to" the English word "soul" through it's PIE(?) equivalent <== i don't know that word, but, on the way there we might encounter Russian word "сила", "sila", the force... May it be with you!