@ RLPhoto - nothing personal but this near diatribe I've written here is a culmination of of seeing the same hash from the same multiple sources (pg7, pg8), you just happened to have been under the quote button.
I believe you are over blowing the noise issue. All my landscape photos I submit to istock photos came from canon cameras and they have some of strictest standard for files. They do quite well for me.
If you get your exposure right, there should be no issues.
I'm glad istock likes your stuff but that doesn't trump what I and a few other people here have said, repeatedly, ad nauseam about FPN (fixed pattern noise) problems with Canon cameras.
If you're not pushing the limits of your raw files for any artistic or DR compression purposes (and it's not all abstract, really) then you may as well shoot jpg because you'll not likely notice the difference.
It has NOTHING to do with "getting the exposure right."
It has only to do with FPN weakness of the imaging system.
Just because what you, any many others, do works for you, doesn't mean it works for everyone.
We don't shoot the same subjects, we don't shoot the same way. If we did, it'd be pointless for us to both be doing it. What you do is not any more "correct" than what I do, it's just different, and the tool you find adequate does not work well for me.
You want to paddle a canoe with a canoe paddle, sure, works good.
You try paddle a kayak with a canoe paddle, it's not so good any more, is it?
Not all bodies of a given type exhibit FPN at the same level.
I have an early 5d2, I had an early 7d. They both sucked with serious FPN, and so did many other bodies produced in the same time frame. (& yes, I've complained to my local Canon rep directly)
You (RL) may have lucked out with cleaner versions of these same bodies. I, and many others, did not. And the way I want to use the gear I paid good money for is compromised because of these problems. That initially rendered some very expensive outings and shoots a serious loss because I do not accept images with this kind of flaw and even sophisticated post-processed is unable to adequately ameliorate the problem.
FWIW, my 40D, 60D, 350D, 400D, 450D, G11, G12, and needless to say my recent Nikons and even my new Pentax Q, suffice for the same kind of "extreme" shots the 5d2 and 7d fail at because they don't have FPN to the same extent; so can you still tell me it's my technique? Part of my fun comes from pushing the limits of low end cameras to get good images. It's pretty disappointing when "high end" cameras have worse IQ than some very much lower end cameras.
The simple fact is that my 5d2, even with latest firmware, shows FPN in shadows of PROPERLY exposed images, even without any significant shadow lifting. It's not the only lousy 5d2 either. Plenty of people have noticed this same FPN issue, they've posted it in these forums, they've mostly all been rebuked by the regulars, some of which should have the technical knowledge to know better since I've seen such demonstrated regularly.
I'm still hoping Canon will pull a rabbit out of their hat this yeat with new sensor tech that will drastically improve low FPN and low ISO DR while we're at it.
Have a look at my first post on page 5 of this topic if you missed it.www.canonrumors.com/forum/index.php?topic=12029.60
This topic has devolved so far from the OP's initial query as to likely have bored them. It started off with good intentions in the first few pages but here we are again.