Blurry Pictures

Hello everyone!
 
First of all, it's my very first post here - although I'm a DSLR hobbyist since 2010. I'm quite used with the settings for Rebel (my previous one was T1i - passed away when I was trying to get a good shot over a slippery stone on a river shore). Now I use a T3i with the stock 18-135mm kit.
 
I noticed that even from the beginning the photos weren't as good (in focusing) as the ones I had with my T1i 18-55mm. This is a second-hand kit that had probably 20k+ shots before me (now close to 50k). I have already sent the camera to an official repair shop for a general cleanup and check-up and it was retrieved with the status 'fine'.
 
I use to take pictures using the viewfinder + MF, but I also tried using the display + AF and the results are quite similar (it takes a bit longer to lock but it locks).
 
It keeps blurring in a strange way (like depth of field + reflection) and I'd like some help to figure out what's happening. The following pictures were taken without any physical filter attached to the lens.



1/400 f/5.6 ISO100


1/1250 f/5.6 ISO100


1/1000 f/5.6 ISO100


1/160 f5.6 ISO100


1/1000 f/5.6 ISO100

G'day Fernando

Firstly - Welcome to the PT photo forum ... there are plenty of others here with lots of experience and a willingness to help others

Okay - to your camera and the pics ~ and the exposure setting are most helpful

Q- what type of focus point is the camera set to?? ... spot / centre / matrix ???

re the pics
#1 - seems acceptable focus - esp the building at the lower left (but without knowing the focus settings it is hard to know what the camera thought you were actually shooting)

#2 - the dogs are in focus but their rapid movement has caused the blur - I use 1/2000s ~ 1/4000s for animals on the move

#3 - again seems to be in focus but not very sharp. It is possible that there is a tiny amount of blur at the leading edge of the black wings to the white body ... looking at the image at 200% it seems to show some horizontal blur. It could also be that the lens is inherently "just a bit unsharp" at max zoom

#4 - is sharp in the centre / leaf area ~ but maybe not sharp enough for your eye/brain to accept
Also - and this is a memory stretch to my university days doing 'photographic optics' (ie: several thousand years ago) the specular highlights (ie: the shiny bits) at the corners (see top left) have a circular pattern to them, indicating a less then perfect optical solution. The 'fuzzyness / sharpness' of the sand grains at the lower left and lower right fall away into the corners - not a depth of field thing, it's sharpness here - suggesting that this lens might not be 'the best' for closeups

Hope this helps
Phil from the great land Downunder
www.flickr.com/photos/ozzie_traveller/sets/