RM... you're gonna love this if you don't already know about it!
Only available for Canon point and shoots at the moment.
I can do incredible things with my a590is that I could not do before.
If you need help or suggestions with the "Canon Hack Development Kit", I've played around with it a lot.
http://chdk.wikia.com/wiki/FAQThis is the site where I found out about CHDK...
http://hackaday.com/2008/05/27/how-to-expand-your-camera-with-chdk/Also, go here...
http://chdk.wikia.com/wiki/CHDK_for_DummiesI'm sure all the DSLR lovers will argue this point, but it added to my $200 dollar camera what is very similar to DSLR functionality.
Since my point and shoot can also have add-on external lenses, the camera/chdk/and lens kit is about the best bang for the buck.
quoted from the chdk wiki...
I've made red the items that will be of most help to you in this "shoot the moon" experiment."Q. What does the CHDK program do?
A. CHDK enhances the capabilities of your camera in a non-destructive, non-permanent way.
After loading of CHDK program you will get the following functionality:
*
Shutter-priority (Tv) exposure - via shutter value override feature * Aperture-priority (Av) exposure - via aperture value override feature
*
Shooting in RAW, with RAW Average, RAW Sum, and RAW Develop features * Live histogram (RGB, blended, luminance and for each RGB channel)
* Zebra mode (a live view of over and under-exposed areas of your picture)
* Depth-of-field (DOF)-calculator, Hyperfocal-calculator with instant Hyperfocal and Infinity focus-set, and more
* Battery indicator
* RAW and Video space-remaining gauges with custom low-limit alerts
* USB cable remote shutter release
* Motion-detection trigger - automatically fires camera on motion detection. (Fast enough to capture lightning strikes.)
* Customizable high-speed continuous (burst) Shutter-based (Tv), aperture-based (Av) and ISO-based exposure bracketing (unlimited shots)
* Focus bracketing (unlimited shots)
* 99 constant bit-rate and 10 constant-quality video compression levels
* Elimination of 1 Gig video-size limit
* Zoom during video function (for cameras without this feature)
*
Shutter, Aperture, and ISO Overrides *
Ultra-long shutter speeds - up to 64 seconds, and much longer on some cameras. * Ultra-fast shutter speeds - up to 1/10,000" and higher
* High-speed Flash Sync at all speeds up to 1/64,000 second (even faster in some cameras)
* Custom user-editable visible Grids for framing, cropping, and alignment
* File browser
* Text reader
* Calendar
* Some fun tools and games
* Fully customizable CHDK display, info placement, user-colors, fonts in menus, etc.
* Custom CHDK user menu (for instant recall of up to 10 favorite functions)
*
Scripts execution - including exposure bracketing, focus bracketing, intervalometer and more) * And other features too numerous to mention here. See the CHDK Firmware and Allbest Firmware usage pages for a more complete overview.
These features work on all camera models supported by CHDK. The camera does not need to have "related" or "inherent" features already present - CHDK will add the required functionality. New features are accessed through CHDK-specific menus, rather than the default camera menus.
As CHDK is continually evolving, new features are often added. Thus, some of the listed features depend on you using a version of CHDK that has those features. Check out the Downloads page for information on finding the right build for your needs."
And, to build on what others have said, bracketing will get you the pictures I think you're after. What bracketing does is take several (as many as you set the camera to take) shots all at once but a different exposure for each shot, then in photoshop go to file>automate>merge to hdr. This involves setting your color balances, etc. What this will do for you is give you many exposures to work with and you can pull the best parts from each one to make a fantastic looking photo that you could never get from a single exposure... this is the new digital photography