40 C H A P T E R 4 Teach Your Camera New Tricks4.3.7 FlashMost Canon compact cameras have rather limited flash functionality. MySD1100, for example, supports the following modes: Automatic, Off, andOn (in manual mode). Red-eye correction and a red-eye lamp can beswitched on, and in manual mode there is a Slow Sync option. However,there is no way to control the flash power. This is unfortunate; it’s hard touse the flash as a fill light.Once again, the CHDK comes to the rescue with an override. There is anoption to enforce manual flash even when the camera is in automaticmode, and the flash power can be controlled in three steps: weak (0),medium (1), and strong (2). When using the flash as a fill light, the mediumand weak settings can be especially useful. I certainly would like a morefine-grained flash control with the option of controlling the flash power in1/3 f-stops; but, you can’t have everything. The three flash power settingsof the CHDK are better than nothing. The strong setting comes in handyFigure 4-24This detail of a night shot showsmassive graininess in the top image.This was caused by setting the sensorspeed to ISO 6400 (market) on a CanonDigital Elph 1100 IS (Ixus 80 IS).Exposure time was 1/20 sec, aperturef/2.8 at 6.2 mm (equiv. 38 mm). Theimage was shot hand-held as a DNGimage with Bad Pixel Removal. Theimage at the bottom, in contrast, wascomposed of the image shown at thetop and seven more similar images, allshot hand-held. Registration andaveraging was performed withPhotoAcute Studio. No other noisereduction techniques were applied,so there is still room for furtherimprovement.Figure 4-25The commands for controlling themanual flash are reached through themenu Extra Photo Operations. You’llfind them at the end of the menu.
