Preferences window

To open the Preference window use the menu command Settings\Preferences.

General tab:

Accelerator for dragging the image - makes navigation in the main window more efficient by moving the image faster than by a mouse.

Brightness management - choose between "curve" and "equalizer" mode of the brightness equalizer.

Ignoring the EXIF information option can be useful if you do not want to include EXIF in the output image.

Help Hints appearance select lets you define behavior of the tooltips. When you place a mouse cursor over a slider or a button, additional information about it will be displayed as a tooltip or in the status bar, in both places or nowhere at all.

Enable noise reduction by default option defines if the noise reduction tab is enabled or disabled when user resets all options.

Reset settings for new image option defines if the settings stay intact or are reset to default when the user loads  the next image.

Restore the last file settings option defines if the settings that were used for previous editing should be loaded.

Check for updates checkbox defines if the program should check availability of newer versions. This may cause problems under some network configurations.

Automatically rotate image when opening checkbox tells the program to use EXIF information about the image's orientation.

Open last edited image on program start checkbox controls if a recently edited image should be automatically opened.

Allow to use external plugins checkbox defines if the program should search for compatible Photoshop-compatible plugins and show them in the menu.

Use the following color profile when saving images checkbox tells the program which color space to use. Please note, that many programs do not correctly display images in color spaces other than sRGB. So it may be a good idea to convert to sRGB before sending image to other people. But converting from Adobe RGB to sRGB  may result in some color clipping.

Cache tab:

Enable cache for thumbnails  option defines if the program saves the thumbnails onto a disk for future use. Each thumbnail takes only some 10-15 Kb (less then 1% of the image size) but the cache significantly increases the speed of the navigation panel .

Enable cache for settings of processed images  option defines if the program should restore the settings that were used earlier to process this image. This can be very useful if you are not satisfied with the result and want to change only some parameters leaving the others as they were set during the first processing.
 

RAW tab:

The Raw format select contains all RAW formats supported by the program. You can set parameters for each RAW format individually. Please select the RAW format to see which parameters are available.

Parameters for RAW development without manufacturer's SDK:

The Demosaic method select lets you choose between linear, medium quality (VNG) and highest quality (AHD) methods of interpolation. AHD will sometimes result in fewer color artifacts around sharp image edges, but it can be applied only to some RAW formats.

To get more information about VNG and AHD methods, please read http://www.aim-dtp.net/aim/digicam/dcraw/vng-ahd-comparison.htm

The Adjust contrast  checkbox  tells the program to clip shadows and highlights to increase overall image contrast. Some minor details in shadows and highlights may be lost.

The Use camera white balance  checkbox lets the program use information about white balance which is available in the RAW file. Otherwise no color correction is performed.

The Use CIECAM02  checkbox controls a type of color algorithms used during digital camera raw processing.

CIECAM02 is a color appearance model that describes the transformations
between colorspaces where the overall characteristics of the scene are taken into
account.  If not checked a more precise method is used that offers less scene characteristic adjustment than CIECAM02 does, but frequently provides better image characteristics in dimly lit portions of a high dynamic range image.

The Set white balance as on the thumbnail checkbox makes the program use a thumbnail as a source of white balance and contrast information. 

Camera manufacturers often hide and encrypt white balance information. Thumbnail is generated by a camera and often it is more adequate than the converted raw file. Please note that this operation is performed on the final stage of RAW development so all previous options may be completely overridden.

Canon RAW parameters:

The Use camera defaults  checkbox defines if the Canon SDK’s default processing will be
used and other options  will be ignored.

The Contrast select controls the image contrast.

The Color depth select controls the image color depth.

The Enhancement select controls the performed enhancement of the image.

The Light source select controls the lighting source assumption made during image
processing.

Kodak RAW parameters:

The Light source select controls the lighting source assumption made during image
processing.

The Exposure bias select defines the exposure gain to use for the image being opened. You  may try to use negative values to save overexposed highlights.

The Color reproduction select controls a color accuracy during the development process.

The Final processing select defines a saturation of the image. Portrait mode produces less saturated look when capturing images of people.

Nikon RAW parameters:

The Use Nikon SDK checkbox defines if Nikon libraries should be used to open a RAW file.

 

 

Audio/Video tab:

Play sound for events  option lets you choose if you want to hear beep after long operations. 

Play voice comments automatically checkbox defines if the associated sound is played when image is opened.

Sound volume slider defines the volume for voice comments.

Audio device select lets you choose from available sound cards and other audio devices.

Audio source select lets you choose the input line of your sound card.

Quality select offers you a list of available codecs. Higher bit rates usually correspond to higher quality and file size.