See first pair depart from peak on big screen? (4)
I believe the answer is:
imax
'big screen?' is the definition.
(I've seen this in another clue)
'see first pair depart from peak' is the wordplay.
I cannot really understand how this works, but
'first' could be 'i' (I in Roman numerals eg Elizabeth I) and 'i' is present in the answer.
'peak' could be 'max' (I've seen this in another clue) and 'max' is located in the answer.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
'on' is the link.
Can you help me to learn more?
(Another definition for imax that I've seen is " large-screen cinema".)