Small image, minute one doctor developed (8)
I believe the answer is:
microdot
'small image' is the definition.
'microdot' can be an answer for 'image' (microdot is a kind of image). I am not sure about the 'small' bit.
'minute one doctor developed' is the wordplay.
'minute' becomes 'm' (abbreviation).
'one' becomes 'i' (Roman numeral).
'developed' indicates anagramming the letters.
'doctor' with letters rearranged gives 'crodot'.
'm'+'i'+'crodot'='MICRODOT'
Can you help me to learn more?
(Other definitions for microdot that I've seen before include "Small amount of drug" , "Subminiature photo" , "Tiny photo" , "Minute photo" , "very tiny shot" .)