Anyway to check to see if a lens is in focus?

TurnipFarmer

TurnipFarmer

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Name
Aaron
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I have just used the kit lens for the first time while away on my Sony A700, the lens in question is Sony f3.5-5.6 18-70mm. The images just dont look as sharp as they should be, having experience from using this lens with my A200 they should be sharper (please note the lens I use with my A700 is a different 18-70mm than the one I had with my A200).

Is there a way of testing the AF on a lens?
 
stick the camera on a tripod and take some photographs of some newspaper stuck to the wall. if your camera has a mirror lockup and self timer, use these to reduce the possibility of camera shake.

if you do it on a nice bright day so you get a good shutter speed (say 1/1000 or more) then you'll definitely know if af is out.
 
I saved this link from another thread here to check if my lenses needed adjusting (they don't).

Forget all the stuff about canon lens corrections and just download that image. When it is in perfect focus you get funny circle patterns appearing all over it. Even the tiniest movement on the manual focus and they vanish - if it was in focus to start with.

Only works with the image on a monitor and zoomed to 100% (even if you don't have the whole picture on screen). don't print it out.

impressed me how sensitive it was when I tried it using with a laptop and the camera on a tripod the other day.
 
RobertP Just tried that photo and I get loads of circles all over the image, so is that correct? I did notice that I did not have supersteadyshot on when taking most of these photos, doh!, I think I should have had that on do you think? I always thought when on a tripod it should be off but it was quite windy when I turned it off, what is the rule of thumb when using image stabilisation and tripods?

I am going to try the cereal box and ruler in a min.
 
Its a pretty crap lens, and IMHO not really up to the A700's resolution demands.

Definately keep SSS off for tripod shooting!

When I compared an 18-70 kit lens vs an 18-55 the 18-55 smoked the 18-70.
 
puddleduck do you think I should get a new kit lens? any recommendations?

I am sure that the lens is in focus using the check that RobertP suggested. I could not get the cereal box thing working.

Also I think for most of the shots I took without using a tripod I forgot to put SSS back on doh! so thats probably why they are not as sharp as they should be.
 
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