In Thief Gold, the gamma doesn't seem to have any effect.

I've tried the solution here http://www.gog.com/forum/thief_series/gamma_adjustment_problem_in_thief_gold/post2, but I couldn't locate the line.

Here is my cam_ext,cfg file:

; $Header: r:/prj/cam/src/RCS/cam.cfg 1.14 1998/09/23 20:00:41 mahk Exp $

; hey, which game is this
game dark

; general configs
include_user_cfg user.cfg
editor_include_dromed_cfg dromed.cfg

; game specific paths/configs
dark_include_install_cfg install.cfg

shock_resname_base r:\prj\shock\art\finals

; set trait cache to include concretes
trait_cache_flags 2
;skip_intro
sfx_device 1
game_screen_depth 32
game_hardware 1
game_screen_size 800 600
sfx_channels 8
game_screen_flags 45
game_full_screen 1
master_volume -1
always_play_intro
skip_starting_checks
vmCenterY 0.5014409423
vmCenterX 0.5007849336
always_play_intro
skip_starting_checks
sfx_vol_3d 0
enhanced_sky 1
d3d_driver_index 0
reverse_stereo 0
sfx_vol_music 0
sfx_vol_2d 0
render_weather 1
gamma 0.5
fogging 1
ambient_volume 300


Can anyone let me know how to increase the brightness?

Thanks.