STALKER: Clear Sky Tweak Guide

[Page 4] Patches & Mods

Official Patch

STALKER: Clear Sky has already received several patches, bringing the English version of the game up to Version 1.5.10 - the version number of your game is shown on the bottom left of the main menu screen. Note that there are three different versions of the International update for the non-Russian version: a retail version for boxed copies, a version for downloaded copies, and for those who purchased Clear Sky using Steam, you should update directly within Steam. Make sure to use the correct update method, or if in doubt, check for updates directly from within the game (see further below). The latest patch contains some bug fixes and multiplayer-related anti-cheat improvements.

Importantly you can use saved games made under any previous version from 1.5.04 upwards after applying this patch, you don't need to restart the game from the beginning. However the patch will reset all your settings, and also lose any custom changes you have applied to the user.ltx file. You will need to readjust your settings and reapply all the advanced tweaks from scratch (don't just copy your old user.ltx over the new one).

To check for an update to your copy of Clear Sky at any time, you can do one of the following: either start the game, click the Options button, and under the Game tab click the 'Game Updates' button to automatically check for any new updates; or go to the main Options menu which opens when the DVD is inserted into your drive (or run the AutoStarter.exe file on the DVD) and click the 'Updates' button.

I will always post details of and links to the latest patch here when it is released, so check back here regularly if you want notification of an update and to find out about the impacts it has on the game.

Click to enlarge

Copy Protection

The International (European, North American and Australian) versions of STALKER: Clear Sky use the TAGES copy protection system, while the Russian version of the game uses the Star-Force copy protection system. The game requires that the DVD be kept in the drive while playing, and TAGES also installs two system driver files called atksgt.sys and lirsgt.sys. Note that there are know startup problems due to TAGES, such as the system not recognizing the game DVD at times or opening the game in windowed mode - see the Troubleshooting Tips section for more details of workarounds.


As modders have already demonstrated with Shadow of Chernobyl, STALKER's X-Ray Engine is capable of being heavily modified, and since Clear Sky is based on the upgraded X-Ray Engine 1.5, it is also similarly highly moddable. The basic instructions on mod creation and mod use in Clear Sky are much the same as in the original STALKER.

If you want to try your hand at modding, to modify game files, you will first need to extract the game's various assets from .db archive files held under the \Program Files\Deep Silver\S.T.A.L.K.E.R. - Clear Sky directory - you can use this Clear Sky Database Unpacker to extract/unpack the .db file contents. Once the files have been extracted to their relevant subdirectories under the main Clear Sky directory, they can be edited or modified as desired.

To allow modified files to work with Clear Sky, you will first need to edit your fsgame.ltx file found under the \Program Files\Deep Silver\S.T.A.L.K.E.R. - Clear Sky directory. Open this file with a text editor like Notepad, and find the following line:

$game_data$ = false| true| $fs_root$| gamedata\

Change the false to true, i.e.:

$game_data$ = true| true| $fs_root$| gamedata\

This will tell Clear Sky to first load up any game asset files which exist in the appropriate subdirectory under \Program Files\Deep Silver\S.T.A.L.K.E.R. - Clear Sky, before attemping to load them up from the archived .db files. In other words this allows you to use modified files, and have Clear Sky recognize and load these instead of the original versions stored in the db files. If you've downloaded a mod, follow the directions which come with each mod as to where the modified files should be placed. Typically all you need to do is just extract the mod contents to the main directory above and it will create the appropriate subdirectory.

Some of the more useful mods which you may like to try in Clear Sky include:

Float32 Shader Mod - Float32 makes the graphics more realistic by adding better lighting and sharper surface effects for example, and can also improve performance. Note that some elements of previous versions of Float32 have already been incorporated into the game engine by GSC.

Update: The original site of the Float 32 mod has gone down permanently. While the mirror above should be safe to use, Float 32 may not function properly on the latest version of Clear Sky.

Speed Up Time Mod

No Loading Disk Mod

Weight Mod

Carry Mod

Real Weapon Names Mod

Obviously many more mods will come out as existing STALKER modders get to work on Clear Sky. Keep an eye on places like:

Filefront STALKER Mods

The Official STALKER: Clear Sky Mods Forum

Oblivion Lost Mods Forum

The next section of the guide looks at the In-Game Settings for STALKER: Clear Sky.