Extra Features For Canon Powershot Cameras User Quick ... - Wikia

Focus Bracketing is the taking of a series of photographs where the point of focus is moved incrementally
between each shot. This is usually applied to macro applications where depth of field is notoriously
shallow. But there's something much more fun we can do with a handful of focus bracketed shots!
"DoF Stacking" (Depth of Field Stacking) is where we combine a selection of focus bracketed photos in a
similar manner to the way that three or more images are combined to make single HDR photos.
Presumably, the term "stacking" most likely comes from the physical stacking of different negatives to
obtain a desired effect of a photo during film processing in a darkroom. (Anyone remember those?) The
resulting image from DoF stacking can have usually paradoxical qualities; the superb detail of a macro
shot with the depth of field of a landscape shot. CHDK makes it possible.
(Note: When using Custom Timer mode for bracketing, the shutter button requires just one press, not
held down as in Continuous mode)
"Bracketing" is the taking of a series of shots with an incremental, usually subtle change in a variable
between each one. Bracketing can be done with changes in shutter speed (Tv), ISO, aperture value (Av),
Focus, etc, and though a bit challenging, several variables can be bracketed in combination, as well.
Usually bracketing is done in order to cover a range of the variable values in an effort to capture the best
of several shots, ie: to capture a perfectly exposed shot. Cameras enabled to bracket out of the box are
usually either DSLRs or high end compacts, and they usually only bracket for exposure, (AEB) and
mostly 3 shots maximum, CHDK allows bracketing in all the values mentioned above and for as many
shots as you want, for HDR imaging for example. Bracketing can be done with specialized scripts as
well, ie: to create HDR timelapse series.
Bracketing can be done hand held, "on the fly" so to speak, and is most likely done in "Continuous
shooting" mode, also in Custom Timer mode if the camera can take multiple shots in that mode. A tripod
is recommended for most bracketed series though to avoid alignment issues when stacking in processing.
Usually, the photos are viewed after download side by side as thumbnails (or further scrutinized in a
browser), the "pick(s) of the bunch" is kept, and the rest are discarded.
Bracketing notes
! ! ----------------------------------------------------------------------------------------------
Kite aerial photography (KAP) is a hobby and a type of photography. A camera is lifted using a
kite and is triggered either remotely or automatically to take aerial photographs. The camera rigs can
range from the extremely simple, consisting of a trigger mechanism with a disposable camera, to
complex apparatuses using radio control and digital cameras. On some occasions it can be a good
alternative to other forms of aerial photography.
(From Wikipedia - http://en.wikipedia.org/wiki/Main_Page)
CHDK scripting has become popular among the Kappers, automating cameras, and reducing the need for
mechanical apparatus.
See: Example Pics on Page 62.
49
! ! ----------------------------------------------------------------------------------------------
See: http://chdk.wikia.com/wiki/DoF_Stacking
KAP
!
!
Zebra mode [Blink 1, Blink 2, Blink 3, Solid, Zebra 1, Zebra 2]
Determines how the over/under exposed areas will be indicated.
Draw Zebra Enable [•] / Disable [ ]
Enables the drawing of over/under exposure indicators.
Zebra is a feature that indicates over and under
exposed areas of the scene. When the shutter is halfpressed,
the areas of the scene that are under or over
exposed will turn red. The zebra effect can also be
applied to existing images by half-pressing the shutter
during playback mode.
! !
Zebra parameters < Main Menu
! ! ! ! ! ! EV Grid Enabled
! ! ! ! ! ! ! ! ! ! ! ! !
! ! ! !
Adds 4 or 5 vertical lines to the histogram dividing the histogram by full stops.
Show Histo Ev Grid Enable [•] / Disable [ ] < Histogram parameters < Main Menu
No Magnification!! ! ! With Magnification
! ! ! ! !
Auto magnify Enable [•] / Disable [ ]
N.NNx in on-screen display. Another tool for controlling the scaling of the histogram. This
option will magnify the Y-axis (vertical) if less than 20% of the histogram area is filled. The
purpose of this function is to make the histogram easier to read when there are very tall peaks.
This function lies somewhere between the Linear and Log options above. A red dot over a peak
indicates that it’s been clipped due to the magnification. The amount of magnification applied is
displayed over the histogram.
24