« on: August 27, 2014, 03:19:52 AM »
Is the 1-stop improvement in JPEG or RAW?
1Dx is at least 1 stop better for noise compared to 5D3.
Is that true - DxO rates the 1DX only 0.28 stops better (http://www.dxomark.com/Cameras/Compare/Side-by-side/Canon-EOS-5D-Mark-III-versus-Canon-EOS-1Dx___795_753 )? And Ken, bless his heart, Rockwell, rates both very similar ( http://www.kenrockwell.com/canon/comparisons/5d-mkiii-vs-1dx.htm#iso )? Perhaps someone who has both could enlighten.
I think Ken Rockwell says the 1D X is half a stop better than the 5D III, although someone with both cameras like FEBS might know better.
He doesn't say that the 1DX is half a stop better, he says that Canon is cheating by having the real iso on the 1DX half a stop lower than the reading it is set at, relative to the 5DIII, so you think it is half a stop higher than it really is.
My 5D Mark III is about a half-stop faster at any given ISO setting than my 1D X.
In other words, at any given ISO, my 5D Mark III gives the same image with a half-stop less exposure. In other other words, my 5D Mark III actually runs at a half-stop higher ISO than marked, or my 1D X is actually running a half-stop slower than marked, or somewhere in between.
It's common for camera makers to cheat a little here, since Canon needs to make the 1D X look like it has better high ISO performance than the 5D Mark III. In this case, it's stacked the deck a little, since when anyone compares at the same indicated ISOs, the 1D X appear to have a half-stop advantage since it's really only operating at a half-stop less ISO than the 5D Mark III at any given ISO. When comparing images, you won't notice unless you shoot at the same manual exposure, in which case my 1D X is a little darker than my 5D Mark III, or if you get both to match, you'll notice that your 5D Mark III only needed about a half-stop less exposure."
The best way to find out if the ISO on a 1dx is much better then on the 5d3 is by using them both. Just as camera makers cheat, it's the same for reviewers who try to explain differences based on poor test and reading manuals but not by using them extensively next to each other.
I read in the mentioned reviews for instance that the AF system of both cameras would be astoundingly the same with the exception of itr. So we forget that the spread of the af points of those 2 cameras is totally different? We forget that the battery voltage of those 2 cameras is different? The itr would be the only difference? But itr only works in af group or af 61 point mode. So even comparing this to the modern systems of nikon would be the same? The same when nikon can only automatically ( no switch off possibility) apply this to all focus point mode.
I'm not the only one on CR that finds the high ISO on the 1dx at least a stop better then the 5d3. I use max 6400 auto ISO on the 5d3, but on the 1dx it's 25600. That's the practical experience I have with both cameras. It's not that I want to say that the 1dx is a much better camera compared to the 5d3. I even use the 5d3 more then the 1dx. I know which camera I take when I want to do a shoot. That's always dependent on the object and my knowledge of the differences of those cameras. But high ISO and superior AF is a big advantage of the 1dx compared to the 5d3. No reviewer can convince me that those to cameras would be the same for this 2 issues. But that's all practical experience with both cameras for using them after a longer period.