Painter who produced 'The Crucifixion (7)
I believe the answer is:
stainer
'painter who produced 'the crucifixion' is the definition.
The definition suggests a singular noun which matches the answer.
This is all the clue.
Can you help me to learn more?
(Other definitions for stainer that I've seen before include "one making his mark" , "British composer" , "Church composer" , "who made his mark?" .)