I'm essentially photographing birds mainly and other wildlife and have had great success with the SX70HS. I previously had the SX50 and SX60 but wore them out and bought the SX70. I thought I'd got a reasonable understanding of the settings required to give me the photos I wanted but I'm now seeking advice from other birders who use this camera model.
In good light, I shoot in RAW and my default settings are on TV (~1/640 - 1/1000) ISO on automatic and centre weighted average meter reading, I'm not sure what autofocus I've had it on as the settings got changed! If the light is very good I'll use AV F8.0 and adjust the ISO between 100 and 320 to give a decent shutter speed.
My problem is that when I'm not particularly close to the subject the images are often not sharp/focused. I'm usually on ~maximum optical zoom so there could be an issue with camera shake but I don't think it is this because if the subject is in isolation, the focus seems OK. Please see the examples below.
The problem seems to be what the camera actually focuses on, even when in the viewfinder the image looks sharp and focused.
What would be my best settings to obtain a sharp image of - say a bird on the ground or on water, any help gratefully received.
Pics attached are close up shot showing sharp focus then a couple of more distant shots and cropped detail showing lack of sharpness. I don't know if the camera is faulty or whetehr I've somehow changed a setting that I'd previously used which isn't as good for these shots [Autofocus on one shot or servo or spot AF, 
