Out of it you may get short of light (5)
I believe the answer is:
optic
'short of light' is the definition.
Although both the answer and definition are adjectives, I can't see how one could define the other.
'out of it you' is the wordplay.
I cannot really understand how this works, but
'of' could be 'o' and 'o' is found in the answer.
'it' could be 't' (abbreviation. e.g. in 'tis) and 't' is located in the answer.
The remaining letters 'pic' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
'may get' is the link.
Can you help me to learn more?
(Other definitions for optic that I've seen before include "Device for measuring dispensed alcohol" , "Device for measuring out spirits" , "Spirit measuring device" , "Of sight or the eye" , "Alcoholic drink dispenser" .)