I have noise reduction turned off at all ISO settings until you get to ISO1600 because I never use higher than ISO 400 ever, I always feel if I need a higher ISO than 400 (which even then is hardly ever used) then i'll use a tripod. I'll try with ISO 800 in the daytime when my girlfriends kids are in the park playing again and see what the noise, image sharpness etc..looks like.
Yeah the issue really is the fact that your subject matter is moving.
Your shutter speed is too slow, which means the subject moves during the capture, giving you blurred photos.
You can't tripod or shake reduction that out of the equation.
The AF seems fine here. The low shutter speed is your issue from what I can see.
Use TAv mode, set the aperture at f8 and the shutter speed at 1/800. Let the ISO float up to a max of 1,600 and lets see what you come back with.
I use RAW only for shots out of my DSLR (not saying you have to, that's just me). Part of my RAW development process (workflow?) is to adjust the noise reduction as necessary. Where the subject matter permits, then yes, you'd want to keep your ISO low and tripod mount etc, but kids running is a different use case altogether.
I would apply the 'girlfriend digital imaging IQ test' (in my case this is known as the 'wife digital imaging IQ test) .... Start by setting set a higher ISO, say 800 or 1600, and then check that the shutter speed is high enough for the motion and focal length (so you're looking towards 1/700th sec or shorter). You use these settings to take some great, sparkling, sharp and crisp pictures of happy smiling kids running around .....
Now show the girlfriend, and as she is fixated on the beautiful pictures, staring lovingly at the kids smiles, you say ...'umm, I'm sorry, but these were shot at a high ISO, so they are a real compromise, and there is loads of noise that kind of ruins them ' ....girlfriend looks puzzled, you point at a patch of sky and zoom right in to 100% ....girlfriend looks at you like "ok, whatever, can I see the kids again now please' ....
Now, were these portraits where skin textures took up most of the frame, then I would agree that ISO should be kept low. But given the subject matter, and assuming the all clear is given from the test as above, then the small amount of noise likely is hardly a true compromise, and could easily be cleaned up with simply NR processing.
McGregNi wrote:I would apply the 'girlfriend digital imaging IQ test'
Ohhh, you mean Image Quality IQ test, not 'Intelligence Quotient' IQ test. That nearly went badly...
Fully agree though Nigel, emotional content over technical quality.
Reality is the sensor/lens combo is not capable of capturing enough light in a short enough space of time, so as to capture a motion free image at very low ISO. Something has to give, and I'd pick a sharp picture over an increase of noise, especially in a 24MP image you're going to downscale and view on a 2MP monitor.