Originally Posted by Brad
My D2X and 5D shoot 13 meg RAW images and compressed jpgs. I used to shoot only raw but switched to jpg as I can hold so many more images on a 2Gig card (I only have 7 cards so space goes quick on a full day of shooting). Has anyone really noticed a difference in image quality when just shooting jpgs? I want the very best but am afraid running out of space or switching cards too often may be foolish if the final image is the same. Looking for input....
Here are some thoughts on the whole subject of RAW vs JPG:
Actually every one on this list shoots in the RAW mode if they shoot digital!
What you say, how can that be? Some are shooting JPG aren't they?
When you press the shutter release on your Canon 20D, the sensor is exposed to the scene that you've framed in your viewfinder. It records the information in that scene. After the exposure is over, the data from that shot is sitting in a memory buffer in the camera. And that data, at that point is essentially the RAW data of the shot. It has not yet been converted into JPG or the ultimate RAW format that will be saved.
So what happens at that point?
The camera checks your settings and the computer in the camera does a number of things. Suppose you're set for JPG only. Then the camera uses its built in RAW converter to convert the RAW data in the buffer into a JPG file and it writes it out to the CF card. If you have chosen RAW, then it simply compresses (lossless) the data and writes it out to the CF card. It also calls on its RAW converter and makes a small JPG which it embeds in the RAW data file written to the CF card. This is the image that you'll see on your LCD. If you choose RAW + JPG, then it does all of the above and saves a JPG in the size you specified.
So, like it or not, you are shooting in RAW and you are making use of a RAW converter!
The question might then arise, which RAW converter is best? Is a RAW converter built into a very small computer inside of your camera with very limited memory able to do as good a job in converting the RAW data to JPG as a huge program on a large super fast modern computer system?
When you depend on the camera to do your RAW conversions, as you do when you shoot in JPG only, you are giving up many of the choices that could be made in the process. Essentially all you control is what you've set for the WB and what you've set for the parameters. And you're pretty much locked in to what you set for the basic exposure information.
If we compare this to the film world, then shooting digital and using JPG only is like shooting slide film in the pre-digital days. You need to be right on for your WB and for your exposure. In fact you usually have less than 1/2 stop leeway. If you shoot RAW, it is more like shooting negative film in the pre-digital days. You may have up to 2-3 stops of leeway. Naturally in the film days you chose film types for your WB or used filters to get the proper WB.
If you shoot every shot with the correct WB and the "right on" correct exposure and you frame the photo in the view finder exactly so that no cropping will later be needed, you will get great JPG photos. But if any of these three decisions is off by very much, you will have great difficulty in correcting it later without comprising he ultimate image. With RAW you do have the extra leeway. With RAW you also have the opportunity which you never have with JPG to extend the dynamic range by multiple processing of the image in the RAW converter. Now you might argue that you could shoot multiple JPG shots and different exposures and then combine them, and this is true for a static scene, but not possible for a non-static scene.
But bottom line is, whether you like it or not, you are all shooting RAW and using a RAW converter. Maybe the choice you want to think about is whether you want to use a very limited RAW converter or a more powerful one.
Just some food for thought.
Here is an example of a shot made in RAW + JPG, so that the same shot could be used for comparison. Since the comparison photo is oversize, I'm just linking to it.
Notice the fine detail differences. Keep in mind that this is extra detail that will become more important the more you manipulate the photo.