Digital Camera User Manual

Curves Notes

Custom Curves

Enables the use of custom "curve" proﬁles to adjust the exposure of your RAW and JPEG images. Please

read this long thread - Custom processing for JPEG (Tone curve, CA ...) :-

http://chdk.setepontos.com/index.php/topic,932.0.html at the CHDK Forum, for its full functions and use.

As well as downloading a custom-curve editor (PC) to create your own proﬁles. (You may have to login

there to download any attachments in the posts.) For those of you new to curve adjustments to exposures

there's a nice little overview to what they do and how they might affect an image in this Curve

Anthology:

http://www.curvemeister.com/support/curvemeister2/help/Articles/CurveMoves.htm

Difference between CV and CVF curves: CV curves are the standard RGB curves. CVF curves are

special versions of the curves which intends to avoid color shift side effect of the RGB curves. They are

an approximation of the luminance curves. Except the SYSCURVES.CVF ﬁle, it is recommended to put

the curves ﬁles in the \curves directory.

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Scripting Notes

Well! where do we start, it is well known that Scripts and Scripting deserves a manual of it’s own, but

for this limited size User Guide we will have to be content with a very brief overview.

Deﬁnition of a Script: A simple program in a utility language, another term for macro or batch ﬁle.

In computer programming, a computer script is a list of commands, or instructions, that are

executed by a certain program or scripting engine. They are usually just text documents that contain

instructions written in a certain scripting language (ie: uBASIC, Lua). This means most scripts can

be opened and edited using a basic text editor. However, when opened by the appropriate scripting

engine, the commands within the script are executed.

In CHDK, scripts are used to automate a command or multiple commands to the camera in order to

have the camera perform certain actions, ie: to hold the shutter open for a particular length of time,

or to force a particular Av or ISO setting, (and many more actions). Nearly anything you can do by

pressing buttons on your camera with your own ﬁngers, you can also do automatically with these

script commands. Note also that many scripts are universal for all relevant cameras, while others

are camera model speciﬁc.

Inventive script programmers, the experienced, and the not so experienced, have been active from

the beginning of CHDK, with many short and simple, and also the more complex scripts being

made freely available to the CHDK community. Scripts such as: motion detect, time lapse, USB

remote.