Hello & welcome taski24 !
The card size doesn't matter, it limits only the amount of images you can store on it, CHDK itself use only < 3MB on the card...
You can use CHDK on your camera without a risk, all informations you'll need are here:
CHDK wikia.
Your A530 will be supported if it has the firmware
1.00a, see
FAQ: How can I get the original firmware version number of my camera ?If you know your REAL firmware version (something like 1.01b, not 1.0.0.1), you can download the latest CHDK version for your camera from here:
CHDK Autobuild Download (use the -full file, e.g. 'a530-100a-0.5.1-514-full.zip').
You should also download
Cardtricks (use the latest version 1.38) to easily install & manage CHDK on the SD card with a card reader.
To install CHDK you should backup all files from your SD card, then format your SD card (either in the camera or with the Cardtricks tool) and expand ALL files & folders from the .zip file to the root of the SD card (e.g. F:\ when F: is your card reader's drive letter under MS Windows)...
Here's also a guid for you:
Let's put the CHDK in the card...
In the .zip file from your CDHK download you'll find a text file
readme.txt with additional informations for your camera modell, read this file.
You should also read the following:
->
CHDK in Brief ->
CHDK_for_Dummies...then do the next step: have fun with CHDK
