All these pictures were taken from a tripod (it was needed due to the long exposures). I took these while sparklers and other small fireworks were being burned. I did not get a chance to play with the settings too much (I think both sets of pictures could have been helped a bit). However, the difference between the DSLR and the SX210 is dramatic.
First lets start off with a picture from the SX210. To start off simple, we just want to see some pattern in the sparklers. We shoot, no flash, and just grab what is there and should get a nice trail. Actually there is a good mode for this already on the camera (fireworks).
Unfortunately, it is hard to get a long enough exposure to really get a long stream from the fireworks. This could be worked going into a manual mode (but A manual mode is more complicated on the smaller cameras, and B due to the limited aperture range, we would still be limited in our timing).
Now for the Digital Rebel. There is no fireworks mode on the camera, but by setting a higher apeture (in this case 7.1) we are able to get the camera to fire for a longer period. Note all pictures were taken in aperture priority mode (so I tweaked the aperture and let the time calculate itself).
There is a bit of the background getting lit up slightly. Might have reduced the ISO (it was 200) and that should have cleaned that removing any background. The advantage of the tighter apeture is increased depth of field (so focusing becomes much easier). This is also evident in the sharpness of the stream.
The stream from the DSLR picture is easily long enough that a word can be written etc. Obviously it is an easy adjustment. Want more time, tighten the apeture, if you want it shorter, open the apeture up. The DSLR definitely wins here for flexibility.
What if we want to see the person behind the fireworks as well (especially for family members etc). Then we would want to fire the flash. Again the SX210 has a mode for this (night protrait), but can also be coaxed to fire the flash and still provide some time for exposure in other modes.
You can see here, that we can definitely make out the person in the picture, but there is not a long trail on the fireworks. Though there is the ability to adjust this, there is not as much (there is not as much aperture range on the SX210 as on the Digital Rebel (will with the DSLR, it is really a function of the lens, but most lenses have considerably more aperture range than a pocket camera.
Finally lets look at the same setup with the Digital Rebel. I used the on board flash (it has more power than the SX210, but there are also external flashes that could be used). Again using the same trick to close down the aperture, and in this case, I bumped up the ISO to 400 (to better grab the person).
This ended up being a 10 second exposure. The problem with this is it is hard for the individual to stand still (especially when waving fireworks frantically), so you get a little ghosting. It is obviously a trade off, opening the aperture (I used 7.1 here again) would decrease the time, which would reduce the ghosting, but would also reduce the fireworks trail. I think the flash did a nice job of grabbing a sharp subject and really overpowering the ghosting (though you see it off to her left).
You can see depending on what you are looking for, it is possible to get nice pictures of fireworks. As the actual firework itself is really bright, small apertures can be used as the bright will still capture on the sensor. Firing a flash can stop action for a particular portion of the picture. This is useful with the fireworks, but can also bring out other portions of a picture (I once took a long night exposure of a tree in the fall that had the leaves change to a fiery color - I walked under the tree and fired the flash up into the tree during the exposure (hiding the flash behind the trunk) for a very nice effect).
With all the talk about how phones are replacing cameras (well the pocket variety anyway), I seemed to have gotten caught up in it. Prior to having a good camera on my phone, I would say I took about 70% of my pictures on the SX210. However, the hard ones, or the important ones, I always grabbed the Digital Rebel. This allowed me to focus where important, but not have to carry the big DSLR around much. I am finding that I now take some of the pictures with my Inspire (though I have not really started to do anything with them).
Though it is possible that the line might blur between the Inspire and the SX210 at some point and the SX210 might lose some of its snaps to the Inspire, the Digital Rebel still has its strengths and will not see its snaps diminished in the least by improved phone cameras (well not for the foreseeable future anyway).