Please watch the video full-screen and at the highest resolution. (I had a hot chocolate just before the video, so my apologies. That's HD for you.)
I've been taking a few shots with my new Canon EOS 600d / Digital Rebel T3i over the last few days, you know, the usual thing, nipping out at lunch from work to snap a few frames. However I felt it was time to start doing a little testing - to see if the sensor on the 600d was indeed better than the one on my old 350d, to see if it produced less noise and more detail.
The answer in case you don't want to watch through the video or read the rest of the article, is yes. At all ISO's the 600d's sensor creates appreciably less noise, and the extra megapixels mean that an awful lot more detail is captured too, meaning that it's possible to crop a lot closer and still have plenty of pixels left for a decent image.
This isn't a scientific test. I've done it so that if you're thinking of upgrading your old Canon dSLR, especially a 350d / Rebel XT, to a 600d / T3i, you'll be able to watch the above video, or look at the below comparison photographs and you'll be able to see the real difference in ISO performance and the level of detail captured by both cameras.
I want you to also bear in mind that the 350d, although only having an 8mp sensor, takes beautiful photographs, and at ISO 100 and 200 there isn't that much difference in the levels of noise.
To do the ISO and detail photographs, I mounted the cameras, one after the other, on a tripod with the same lens and same LED ring light. I used the 18-55 kit lens at f/8 and used manual focus and auto white-balance. I shot .jpg's and did the cropping in Photoshop.
The photos you see on this page can be clicked on so you can look at the full resolution versions, which I heartily recommend. The crops are zooms to 100%, so you can easily see the extra detail that the 600d / Rebel XT captures (the clock is bigger), but also take a look at the slightly out of focus wall area, where you can see the differences in the amount and type of noise from both cameras.
Right, lets get started, here's the full photos from the 350d take at ISO 100, then at ISO 400 then ISO 1600: (Click on the photos for the full size images.)
Now let's look at the shots from the 600d / Rebel T3i, at ISO 100, 400 and ISO 1600: (Click on 'em for full size photographs.)
Right, so you're thinking that these photos were OK, but it's a little difficult to compare the performance of both cameras, so I've taken 100% crops from the images and stacked them together so that you can more easily see the difference between the two sensors.
In this first collage, you've got ISO 100 on the left and 200 on the right, with the 350d on the top and the 600d on the bottom: (Click for full size).
Here's ISO 400 (left) and 800 (right) with the 350d on top, 600d underneath:
This is just ISO 1600, 350d on top, 600d on bottom.
Finally, these two are just the 600d, at ISO 3200 and 6400:
In conclusion then the Canon EOS 600d / Digital Rebel T3i has significantly better noise performance than my old 350d / Rebel XT. The 600d also captures way more detail with its much larger sensor, enabling much closer crops.
I hope this post helps if you're thinking about upgrading your dSLR.