The most common and most likely answer to this crossword clue is the 10 letter word SCREENPLAY
I've seen this crossword clue in The Times
S
C
R
E
E
N
P
L
A
Y
Buddy explains!
The straight part
We know that "specifications for picture" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case specifications for picture = screenplay.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does SCREENPLAY mean?
SCREENPLAY noun- (authorship) A script for a movie or a television show.