Originally posted by Rondec I think honestly, we have known about this. When the kx came out, there were numerous threads
Looking at charts and numbers is one thing; actually taking pictures yourself and comparing them is another. I wasn't planning this as an end-all K-7 vs K-x thread and didn't even do this with the intent of posting it online, I had been reading complaints and debates that came up recently the day before, and did a quick test to relax after a final exam because it was too dark to shoot a real subject and my mind was too dead to start studying for my next exam. This was for personal use that I just thought I would post here for reference..
Originally posted by audiobomber Hi Al. What raw convertor did you use? What settings for NR in the cameras?
I have a K20D and K-x. My testing with NR disabled was a 2/3 stop difference in noise (i.e. ISO 1600 on the K20D was cleaner than ISO 3200 on the K-x). From tests and net gab, my impression is that the K-7 is about 1/3 stop noisier than the K20D, therefore about 1 stop worse than the K-x. K-x and K-r are equal. Having done this test and with access to full resolution files, would you agree there's a one-stop difference in noise?
Aside from noise and 1.5 stops of DR, a K-7 is twice as much camera as a K-x.
Hi audiobomber. They were converted in LR3, without touching any of the settings. The NR in the cameras was set at 'Medium' on both, since that is how I've been shooting with them. 1 stop seems to be pretty accurate, but I am no expert
I do agree with the last statement though; I've just gotten used to shooting with the K-x over the past 9 months, where I didn't really have to think about ISO until getting really up there.
Originally posted by ihasa Of course if the k7 underexposes like that, you would apply ev comp though.
True. The ironic thing is, I've had +2/3 eV dialed on the K-7 for the past 2 weeks of shooting.. but reset it to do this test so that everything would be 'zeroed out'..
Originally posted by Marc Sabatella It's not that we don't appreciate the experiment and the effort taken perform it, but given the difference in focus and in exposure, it's hard to gauge much about difference in noise levels.
If you cared to repeat the tests, what I would recommend is using the same actual exposures for the shots on both cameras: eg, f/2, 1/30", ISO 1600 for both cameras, then f/2, 1/60", ISO 3200 for both cameras, etc. And since it can be so hard to get focus *exactly* the same between shots, I like to use a piece of fabric of or something similar, so I can compare the most in focus area of one against the most in focus area of the other.
Also be sure you have all in-camera noise reduction turned off, unless your purpose is to compare JPEG engines rather than sensors. But if that is your purpose, you also should make an effort to find the "best" NR setting for each camera, rather than assuming that the same setting on both cameras should mean the same thing. Generally, it's easiest to do these shooting RAW then processing the same program using the same settings. Or perhaps do a versipn where you try to find the "best" NR setting in your software for each camera, so you are comparing "best that can be achieved using a given PP program and just basic NR adjustments, no fancy extra plugins/filters/etc" for each. In some ways I personally find that more valueable than a comparison with no NR at all, and certainly much more useful than a comparison of JPEG,s who knows what level of in-camera NR.
I wasn't planning on this being posted on the internet when I did it, I was just curious and passing time. Maybe after exams end I'll repeat it with everyone's advice taken into account and a subject easier to focus more consistently on (and a tripod.. I don't have steady hands so getting remotely usable ISO100-200 shots in that light was a bear). If I repeated it, I would also use the same shutter speeds on both.
As far as in-camera noise reduction, I had it set to medium on both, starting at ISO800. I had assumed (probably incorrectly) that they would be the same, since the bodies came out close to the same time, and I have been using them both on those settings since getting them. I didn't want to do anything at all in post-processing because IMO that's no longer comparing cameras. Finding the 'best' in-camera setting is a good idea though, and probably something I should have done anyway. I'll keep that in mind.
Does the in-camera high ISO noise reduction still process raw files, or only jpegs?
EDIT: Just searched, according to this link, the K20d does no NR on raw files, only jpgs.
https://www.pentaxforums.com/forums/pentax-dslr-discussion/32501-high-iso-noi...thing-raw.html
I've read the same for the K-5, so I would assume the K-7 doesn't either. So ignore where I talked about NR settings, because I guess they're not doing anything.
Cliffnotes: There is no noise reduction in these images.