Some configuration ideas for using the A495 for aerial photos

The Canon Powershot A495 is the camera model of the PLOTS visible/IR camera tool

Personal preferences vary, but these choices have worked well during mapping flights. In some situations, setting the camera on full automatic mode can produce good results. But in general, manual settings are preferred over automatic settings so each photo has similar qualities and will stitch together more seamlessly into a map. The exception is exposure, which is a challenge to set correctly before launch, and may need to change during a flight.

Manual Focus -- the A495 can be set on "infinity" focus mode. The camera has to be in "Manual" mode for this option to appear (have to confirm this). For most mapping flights, everything will be in focus if the camera is focused on infinity. Additional information is needed to confirm how this "infinity" mode works. In some cameras, the focus does not stay locked on infinity.

Daylight White Balance -- When the camera is in "Manual" mode, select the "sun" icon for daylight white balance. This will make color balance consistent, whereas automatic white balance (AWB) allows color balance to vary among photos.

Image Stabilization -- The A495 does not have image stabilization. That's okay because it probably does not help on balloon or kite flights.

Exposure Compensation -- On sunny days, the view from above is bright, and the automatic exposure system can be fooled. The A495 can compensate for such scenes by reducing the exposure in increments of 1/3 f-stop. Setting the Exposure Compensation to -1/3 or -2/3 can eliminate overexposed highlights.

ISO -- On sunny days, ISO 80 (the "slowest" sensitivity to light) should produce the crispest images. On darker days, setting the ISO higher (100-200) will allow faster shutter speeds (less motion blur), but the images will be noisier (grainier). ISO settings higher than 200 are not recommended because the images will be rather noisy, but in dim light this may be the only option. In auto ISO mode, ISO can vary among photos making some more noisy than others.

Manual Exposure -- The A495 has only a full automatic exposure mode. In some situations, this can allow the shutter speed to be set too slow for aerial shots. Enhancing the camera firmware with CHDK adds a shutter priority exposure mode.

Battery Saving Features -- (must confirm with the A495)

• Turn the brightness of the LCD display down.
• Turn the LCD display OFF before launch.
• Turn the autofocus light off.