~/.config/redshift.conf

redshift.conf

; Global settings
[redshift]
temp-day=6500K
temp-night=4800
transition=1
gamma=0.8:0.7:0.8
;gamma=1.000:1.000:1.000
brightness=1.0:0.5

adjustment-method=randr
;adjustment-method=vidmode

;location-provider=geoclue
location-provider=manual

; The location provider and adjustment method settings
; are in their own sections.
; This is an example lat long for Portland, OR
[manual]
lat=47.1615
lon=7.68632

; Configuration of the adjustment-method
; type 'redshift -m METHOD:help' to see the settings
; ex: 'redshift -m randr:help'
; In this example, randr is configured to adjust screen 1. 
; Note that the numbering starts from 0, so this is actually the second screen.
[randr]
;screen=1

; In this example screen 1 is adjusted by vidmode. Note
; that the numbering starts from 0, so this is actually
; the second screen.
;[vidmode]
;screen=1