I used to take photos in the largest file option before the RAW option and never had problems opening or previewing the pix. Now I'm shooting in RAW. My photos look great in my camera viewfinder. However, when I try to open them on my computer (using Picasa 3) each photo has something VERY VERY wrong - large distorted blocks, bright colored streaks, etc. It looks like a problem with opening the pix to preview. Why is this happening? What software should I be using to preview photos? I'm not tech savvy and am afraid to do anything and lose the priceless pix of my son's first prom. HELP!
Just so you know:
Most likely, your files are fine but the software is having trouble decoding the RAW files from your camera. This is a regular occurrence since RAW files are different between cameras. Most software get regular updates to support new RAW formats. Check if your Picasa is at the latest version if you want to use them. Upgrade if it is not and try again.
Otherwise, the most reliable bet is to use software provided with your camera. There is always one on CD. The interface is often poor but it is the most compatible. If your camera is particularly new, which it could be since very few RAW-capable cameras can show images in the viewfinder, this will be the only software capable of understanding your RAW files for a short while. When a new camera comes out, software can take anywhere from several weeks to several months to catch up.