I have recently bought a used Canon A550 and tried using CHDK with it. I firstly wanted to use it as a time-lapse camera, so I installed the Ultra Intervalometer on the camera and enabled RAW file support.
All went well, however, the DNG files that come out of the camera have no preview. I can not use my Mac's Quicklook on the files to check the contents.
The files do have small thumbnails though.
I need to import the DNG files into Lightroom and update the DNG previews & metadata (this function is found in the
Metadata menu when in
Library mode) to get the previews right.
For several hundred DNG files this process takes a while. Is there a way to command CHDK to generate these previews when writing the DNG to the card?