Struggle with force during erection of bloody camera attachment!
I believe the answer is:
viewfinder
'camera attachment' is the definition.
'struggle with force during erection of bloody' is the wordplay.
'struggle' becomes 'vie' (I've seen this before).
'with force' becomes 'wf' (this might be a standard abbreviation which I don't know about).
'during' becomes 'in' (I've seen this in other clues).
'erection of' says the letters should be written in reverse (in a down clue going up is a reversal).
'bloody' becomes 'red'.
'red' backwards is 'der'.
'vie'+'wf'+'in'+'der'='VIEWFINDER'
(Other definitions for viewfinder that I've seen before include "camera attachment?" , "part of camera" , "Press to take picture after looking into it" .)