As is my teaching style (explain-er that I am) I feel it's my job to give you information in a practical and "hands on" way. How does this effect you, and what is really important! So, if your craving an exploded head tech report on the newest items... you have to wait your turn, this isn't that post!
Now lets dive in so we can learn WHY you want to care about this technical stuff!
What is a CCD or CMOS chip:
Both the CCD and CMOS chips are simply an image sensor or the capture device of your camera. It the camera's "film" so to speak. It is where the information is captured before it is digitally stored onto your memory card. It is the brain of the camera, if the eyes are the lens, and the mouth is the memory card. Basically the image sensor job is to take the light gathered from the pixels and convert it to a digital image which is then stored onto your memory card as a file.
What is a MegaPixel ( MP )?
Megapixels are (basically) what your sensors are made up of, it is what "reads" the information and creates the image. Each sensor is made up of millions and millions of pixels (think of this like the grain pieces in old school film if your familiar) They capture, and decipher all the information.
Almost. There is another factor. SIZE of the chip. Yep, I am going to say it. Size does matter. A lot.
This is a really good chart, but you have to put into your mind just how small were really talking... point and shoot camera sensors are smaller then your smallest fingernail. By a LOT.
If you take just the standard point and shoot camera sensor (Red) and put 12mp on to it, they are all going to be really really tiny right? Now, if you put the same 12 mp on say the Pro DSLR "full Frame" (purple) those pixels by default are larger and capture more information in each one. (like almost 20 times larger) so before you even get into differences in lenses, skill or anything else your Pro image sensor is creating a better quality image even though it has the SAME mp rating.
To be fair, most DSLRs are not the purple sensor size... but that does account for the "pro" price on the ones that are! Your typical DSLR entry level or "pro-sumer" that mid range camera would be somewhere between yellow and the largest blue. Which makes a HUGE difference.
You should learn what size your sensor is - so that as we talk about differences in lens, and how your sensor size effects cropping and such you can know how it effects YOU! If you don't already know, open your manual to the "specs" page and it should be listed out there! (consider this your homework, because you need this information for part 2)
Now, some people wont like this... but I am going to point this out anyway... Do you see the grey square, the smallest one on that chart? That's your Iphone sensor, half of that smallest point and shoot camera quality. So, when you ask why I am such a firm believer in not using them for product images... there ya go. Right now, no matter how good it is, its just not comparable based off the sensor alone. It's like watching the first color release of the Disney Cinderella before any remastering or editing... compared to say... Tangled or Brave. Functional, but not very detailed or pretty.
Now... Like a good host, I am going to let you digest your dinner before we get to desert! I find that making technical posts too long is a little overwhelming! So tomorrow I am going to continue this train of thought and share with you how your sensor size is related to printing images, cropping, and even that silly digital zoom you hear so much about.