Canon 70D Viewfinder Blurry / AutoFocus Isn't working fully

[coach41]

I bought the Canon 70D package from CostCo about a month ago.  I also purchased a Canon 17-55 / 2.8 Lens from someone I know.  The combo has been good and I have taken hundreds of photos.  

However, as I was taking some photos tonight, I noticed the view finder was a bit blurry though my photos were coming out ok.  I thought maybe it was the conditions of the gym I was shooting at (cold outside, but warm / heater inside).   Alas, I am home now checking out the camera and there may be an issue.  I checked with the 17-55 lens and also my stock lens from my old Rebel XSI.   The view finder appears to be blurry AND the auto focus on my lense's do not appear to fully functioning.  Again, the photos seem to be coming out ok when I shoot them. 

Any have any thoughts / opinions?  Fortunately, I can easily return the package to costco or exchange it if it's a problem.  Too bad.  I like the 70D and the 17-55 lens I bought.   Fortunately, I don't have a need to shoot anytime soon.  

[cicopo]

Sounds like you've accidently changed the diopter adjustment. Your manual will tell you where the little knob is located.

[ebiggs1]

"... where the little knob is located."

Sometimes it is fairly well hidden!  

[coach41]

Thanks all.  I thought the diopter setting was a SOFTWARE setting.  I was able to give up last night but after posting the message, I found the knob and all is working well. 

What is the purpose of diopter setting?  I looked it up on Wiki this morning and I'm not entirely sure I understand.  : 

[cicopo]

It allows people like me to see things clearly through the viewfinder WITHOUT my reading glasses. It adjusts a bit on either side of perfect vision.