Lens cap shots. You bet!
Well, I had to process them using DNG-converter 8.2rc but that's likely adequate for now.
What I can see is that the noise structure of the 70D's sensor is still typical Canon; lots of noise in the red and blue channels and still a fair bit in green but the noise structures at base ISO are mostly fine-grained and should respond well to NR software.
There is still some larger structured noise banding tho it's mostly broad horizontal banding and unlikely to severely impact most images. Dark-sky photographers pushing to look for dim details my be about the only ones who would run into problems.
edit: BUT - I accidentally took the first 100 ISO dark shot with the info display activated, so rear LCD was ON. The resulting noise levels were much higher (~ between 400 & 800 iso dark shots) than the next 100 iso shot when I turned the display OFF. The 100 iso dark shot with LCD display ON had much more red channel noise than any of the other shots.
200 and 400 ISO are similar but the noise structures are (more balanced) with both H & V elements. Again, these are quite fine and will probably respond very well to typical NR software.
Noise starts to pick up at 800 ISO, noise structure similar to iso 400
1600 and 3200 iso show increasing overall noise levels as expected. Noise structures become a little more obvious but, again, would respond well to NR software and only pushed large areas of continuous shades or tones may bely some of this non-uniformity.
6400 and 12800 are pretty noisy and continue to show some banding structures in both H & V axis butOVERALL, THIS LOOKS TO BE CANON'S BEST APS-C SENSOR IN A LONG TIME.
FPN exists but is at a workably low level and may even be comparable to Toshiba's new sensor as far as noise structures. However, overall TOTAL NOISE is still much higher than the Sony or Toshiba sensors and this will reduce effective maximum DR somewhat but that can be partly negated with NR software.
I would not steer anyone away from using this camera, it's comparable to the 6D for noise quality and certainly bests my 60D and blows away the 7D I used to have.
If you need the ultimate in clean black levels in your raw files then this is still
not the camera for you.
BUT, using some decent noise-reduction software you can comfortably use the 70D in ways that the 7D and 60D before it would disappoint. The 70D is "good enough" for most uses unless you're as picky as I am. I know I could still find some situations where this camera might not perform as well as I'd like.
I could also not find any significant variation in noise structure I could attribute to the areas that were normal pixels VS. the AF pixels so they've done a really good job on that.Polite applause for Canon. They've certainly made some progress in this model.