How To Take Artistic Screenshots

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Introduction

This article covers the creation of artistic screenshots which are higher in artistic quality than typical screenshots. The objective of this article is to approach screenshot creation more along the lines of photography.

Graphics quality

Modern graphics hardware is often capable of much higher quality rendering than what it commonly runs at, as gaming usually involves a compromise between image fidelity and rendering cost. Various tricks such as "anti-aliasing" can help hide jagged, step-like boundaries at the edges of polygons, but at the expense of lowering the framerate on less expensive hardware. However, taking screenshots is not about performance. Instead of rendering images perhaps thirty or forty times a second, our aim is to render a single image which is to be displayed for perhaps minutes at a time - so the aim is to jack your graphics card's settings up as far as they'll go.

NVIDIA

NVIDIA graphics cards command around half of the market, up against arch-rival ATI. On an NVIDIA GeForce 6600, for example, there are graphics settings which are not directly accessible through Half-Life 2's in-game configuration screens - there is an additional "8xS" anti-aliasing setting which is definitely worth pursuing for taking screenshots, due to the significantly improved image quality when rendering masked textures such as foliage, fences and gratings. Examples of some of the anti-aliasing levels available are shown below:

No anti-aliasing - click to enlarge
4x anti-aliasing - click to enlarge
8xS anti-aliasing - click to enlarge

First of all, start up Half-Life 2 with the mod of your choice and set everything except anti-aliasing to as high as it will possibly go; Model detail, Texture detail and Filtering mode will make the most visible differences. An example screenshot is shown below:

Advanced video settings - click to enlarge

Next, quit the game, right-click on the desktop and bring up your Display Properties settings window, then click on the Settings tab. Now click on the Advanced button near the bottom, then on the GeForce tab. We now want to select the highest anti-aliasing mode available, so click on Performance & Quality Settings to the left, uncheck Application-controlled then drag the slider as far right as it will possibly go. In the author's case, this is to "8xS". Another example screenshot is shown below:

NVIDIA display properties - click to enlarge

Click on various OK buttons, and restart the game. In the author's case, bringing up the console and typing "mat_antialias 8" appears to be necessary to enable the "8xS" anti-aliasing. Once this is done, there should be precipitous drop in framerates, so type in "sv_cheats 1" and load your map - the game is now ready for screenshots!

ATI

ATI's Adaptive Anti-Aliasing performs a similar function to NVIDIA's "8XS", smoothing transparent edges of textures. It can be enabled through the Catalyst Control Center in the usual manner. All ATI cards above the X800 Pro range support AAA; however, X800 Pro cards have the feature locked by default. Following this guide will help you enable the option. Note that the level of Adaptive AA is taken from the level of regular AA.

With the Catalyst 6.2 drivers, "High-Quality AF" is also an option, again accessible from the Control Center. This will improve texture filtering, making textures at long distances and high angles appear sharper.

Targa (TGA) screenshots

The standard screenshot function in Source compresses the output to lossy JPEG images, which while great for quickly uploading to the web do result in a loss of quality for any subsequent editing.

To save screenshots in an uncompressed Truevision TGA format which can easily be opened by most, decent image-editing software, it is recommended that you type something like following into the console: "bind f4 screenshot", which will save a TGA screenshot every time you press the F4 key.

Removing the crosshair and HUD

Sometimes when taking screenshots, the aim is to give a visual, near-photographic impression of the map without the presence of any game interface elements. In single-player Half-Life 2 (and most other games and mods), the primary elements are the HUD (head-up display), the crosshair and the weapon model. Fortunately, there are console commands to remove all of these - "cl_drawhud 0", "crosshair 0", "r_drawviewmodel 0" and "impulse 200".

Environmental shots

For this, enable the "god", "notarget", and "noclip" commands at the console - the player character will then effectively become an invisible, free-floating camera. Try to find interesting angles which give a flavor of some of the more interesting sections of your map. Treat it as if you are using a real camera and you are visiting a real place, with the aim of taking aesthetically pleasing photographs rather than merely documenting what is there - with the advantage of effectively infinite film, no need to focus or choose exposure settings and the ability to float the camera absolutely anywhere in the world in order to get the best shot.

Countless millions of pages have been written on real-world photographic techniques, so it is impossible to condense it all into a paragraph here - perhaps the best approach is to experiment, and most importantly, to expect to throw many of your shots away in the pursuit of getting that one, "perfect" image.

Action shots

For screenshots which illustrate gameplay and other dynamic aspects of a map, it can be advantageous to record a "demo" of normal gameplay (essentially a film of everything which happens) and then to take screenshots during its playback - it is much easier to capture fleeting details such as gun muzzle-flashes, explosions and other events this way.

More information is available on the Demo Recording Tools page, which documents Source's highly versatile demo playback facilities.

Another technique is to actually slow down game time by typing "host_timescale x" into the console, x being the desired time scale (i.e. 0.5 scales time speed by half). With this technique, it is possible to orchestrate brilliant battle scenes.

Going beyond the monitor's resolution

Error creating thumbnail: Invalid thumbnail parameters
4096x4096 Screenshot of Dear Esther - click to enlarge

Using this method, you can ignore your monitors resolution and instead hit the limits of your graphics card's maximum resolution, which is 4096x4096 in most cases.

Using the Nvidia Control Panel to create custom resolutions, you can force these a new desktop resolution and then start the Source Engine in window mode with the resolution settings in the command line. If there is a similar method for ATI/AMD graphics cards is yet to be discovered.

Open up the NVIDIA Control Panel and navigate to Display -> Change Resolution -> Customise... -> Create Custom Resolution

Here, you can set your resolution of choice, but keep in mind that not every resolution will work (such as 1920x1). Also, lowering the refresh rate will enable you to achieve even higher resolutions. With a recent graphics model, for example, 4096x4096 is possible at 30Hz.

Only few resolutions will be supported, so it will fail with the error message "Custom resolution xxxx x yyyy at 60Hz (32-bit) is not supported by your display." Nevertheless, the custom resolution will remain until you click OK. At this point, you will most likely end up with black screen, unable to see your desktop. Using remote control tools such as TeamViewer or similar VNC tools, you can stream the video to another display or computer.

Once you can see your high resolution desktop again, boot up your Source game with the new resolution in the command line: hl2.exe -width xxxx -height -yyyy -windowed

After starting the game, it is often possible to revert to your old resolution with the game still running at a higher resolution.

Post-processing

Uploading an otherwise unmodified JPEG version of a screenshot will result in a dark, impenetrable mess. There are, however, some simple tasks you can perform in post-processing which will make the screenshot appear more as it did in-game.

Gamma

The images a typical computer game saves in a screenshot and what it actually displays on screen are usually subtly different, thanks to something called gamma. A way of describing a display's brightness response for a given input value, a game's output gamma is generally different from a typical computer desktop's gamma. A game such as Half-Life 2 will typically brighten low- to midrange-values much more than a normal computer graphics application - in Source, this is controlled using the in-game Brightness dialog box.

To make your screenshots look as they did while you were playing the game, it is thus best to use an external graphics editing program such as Photoshop or, in the case of this article, examples from the free, open source GIMP will be used.

Original screenshot

As can be seen above, the original screenshot is far too dark. So, bring up the Levels dialog box (Layer: Colors: Levels...) and increase the applied gamma from 1.00 - around 1.30 seems to be a good number for typical screenshots:

Levels dialog in GIMP

For particularly dark images, it can be useful to apply "overbrightening" by decreasing the input level's maximum from the standard 255 to something lower - a gamma of 1.3 combined with a maximum input level of 200 can work wonders on screenshots portraying night-time or underground scenes.

Your image should now look something like the following:

Screenshot after gamma correction

Sharpening

If you wish to reduce your screenshot's size, it can be useful to then apply a relatively small amount of sharpening. First, scale it down to the appropriate size (Image: Scale Image...) then bring up the Sharpen dialog (Filters: Enhance: Sharpen...). A value of 10-30 is usually about right - if set too high, black and white fringes may start to appear around edges and other details.

Sharpening dialog in GIMP

Finally, your screenshot should look something like this 400x300 image:

Final screenshot

Saving as JPEG

To save your masterpiece, go to File: Save as..., select the destination and type in the final filename (to save as JPEG, simply end the filename with a ".JPG") and press OK. To see what the lossy JPEG compression will do to your image, click on Show Preview in image window - increase the quality if necessary to remove compression artifacts. Advanced options include 'progressive' (image blurs in when loading, and file is often slightly smaller too) and different subsampling methods (for more accurate colors at the expense of file size).

Conclusions

When combined, the above techniques can be used to greatly improve the images with which you show off your latest work. While they won't cover the cracks in a poor-quality original, they can definitely help differentiate your efforts from the crowd. So have fun, and happy screenshotting!

See also