your new camera has wizbang 10 million point 3D auto-exposure, so I can just put it in “Auto Program Exposure” mode and I will always get well exposed pics, right? WRONG!
not only is using brainless auto-exposure like saying you piloted a Boeing 737 and all you did was press the autopilot button, but it often doesn't give you the best exposure settings you need.
for a start, the camera is not going to know just how you want a subject rendered, you may want skin tones under-exposed for mood, or a little over-exposed for a high-key effect, furthermore, as the camera uses a “reflection” type of light meter it can be fooled such as:
personally, I almost NEVER use “Auto Program Exposure” mode as for a start, the exposure may not be what I want, but even worse, I don't have control over deciding on depth of field, subject motion and image noise, all of which are critical elements in the final outcome.
sure you can “bracket” your exposures by taking 3 photos all with different exposures but this will take up space on your memory card, potentially use up more time taking/saving the images that you might miss the best shot, and worse, end up with the best expression on the wrong exposure.
sure you can check the histogram on your digital, but this applies to your whole image, and if your subject is a small component then you may not be getting the information you need as it is flooded by the remainder of the image.
do yourself a favour and start to think about what you are trying to achieve and consider buying yourself an incident light meter to better understand light (preferably one that can measure flash light as well).
if your camera has a spot-meter then try using this.
try to shoot in
digital camera RAW files mode to give yourself the best options of adjusting exposure after the image is taken.