###Installing and using CHDK###

* There is lots of information at the "CHDK for Dummies" site: http://chdk.wikia.com/wiki/CHDK_for_Dummies
* A CHDK FAQ is here: http://chdk.wikia.com/wiki/FAQ

Follow these steps to "reprogram" an SD memory card for each camera so that temporary firmware is loaded to your cameras when they are turned on.  This firmware provides several useful enhancements including the ability to trigger the cameras remotely via the USB port.

"CHDK" or Canon Hack Development Kit must be installed on the camera's SD card.  It loads each time the camera is turned on, and does not change the camera permanently.

###Choosing an SD card###

* 4GB cards are easier because larger cards require partitioning in order to run CHDK and use more than 4GB. 
* 4GB cards are $5-10 online or a little more at a local store.
* Cards must be "SDHC"
* For multiple long flights in one day, more than one SD card per camera might be needed.

###Installing CHDK on the SD cards###

* The firmware version on the Kickstarter A495 cameras should be "100F", so the matching CHDK  file **a495-100f-1.0.0-1820-full_BETA.zip** is available at http://mighty-hoernsche.de/bins/a495-100f-1.0.0-1820-full_BETA.zip (mirror)

###Installing using a PC###
* Follow the instructions here: http://chdk.wikia.com/wiki/CHDK_For_Newbies_-_How_To_Install
* This requires using the clever program called CardTricks: http://chdk.wikia.com/wiki/CardTricks

###Installing using a Mac###
I had to run this command in the terminal on the files in the SD card to make them executable (on a mac):

    cd /Volumes/CANON_DC
    xattr -d com.apple.quarantine DISKBOOT.BIN PS.FI2

as outlined here: http://chdk.wikia.com/wiki/FAQ/Mac#Still_Having_Trouble.3F

* (add videos?)

###Basic CHDK settings to start with###

*Enable Remote*
To allow remote shutter release via the USB port, you must enable remote operation. In the CHDK Main Menu select **Miscellaneous Stuff/Remote Parameters/Enable Remote**. 

*Synchronous Shutter Release*
To precisely synchronize the shutter releases of two cameras connected to a timer, you must enable synchronous remote in CHDK. In the CHDK menu, under **Miscellaneous Stuff/Remote Parameters**, turn on **Enable Remote**, **Enable Synchable Remote**, and **Enable Synch**.

With this setting, CHDK uses the first signal from the timer to get ready to take the photo (focus, exposure, any other auto stuff) and then takes the photo on the second signal. The timer must be set accordingly.

###Some options available when CHDK is installed###

*Shutter Priority* -- The Canon A495 does not have this option, but CHDK adds it.  It allows the camera to set the exposure automatically while keeping the shutter speed high (thus reducing blur).  On sunny days, setting the shutter speed at 1/800 second is suggested (the IR camera may require more light and a lower shutter speed).  To use shutter priority in the CHDK menu, select **Extra Photo Operations/Disable Overides** = OFF, then **Overide Shutter Speed** = 1/800 (or whatever), then **Value Factor**=1. Generally you should deselect or turn OFF everything else on that menu page.

###Configuration using the camera's normal menu settings###

Personal preferences vary, but these choices have worked well during mapping flights. In general, manual settings are preferred over automatic settings so each photo has similar qualities and will stitch together well.  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. Some additional information is needed to confirm how this "infinity" mode works.

*Daylight White Balance* -- When the camera is in "Manual" mode, select the sun icon for daylight white balance.

*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.

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

* Turn the brightness of the LCD display way down
* Turn the autofocus light off
* Turn off the LCD display before launch.