simdavid

Hi,

I have tested extensively on the focus problem on my K20D, wasting quite abit of my shutter..lol. My case is not a front focus issue because I adjusted it with the K20D Focus Adjustment feature and it back focus when shooting on easy contrasty target. I shot focus chart like yours and they are in perfect focus without adjustment. It is a problem with how the AF system determine what to be focused in the spot focus red square. I used spot focus all the time and at wide angle, I found that the AF focus can be off sometimes, so it is not all the time, it does get it right sometimes. So my own deduction of testing and reading up on other information is at wide angle, it can be hard for the system to determine focus when contrast is not well defined. I hope this helps.

Hi
That is what I do to see in clear focus. I saw that few of the K20D users face the same issue. I’ve learned it’s a know issue over AF (“front focus”) and after writing to Pentax support they reply “At this time there is no firmware upgrade for the K200D that would address a lens front focus issue. I recommend you send the camera and your DA 18-250mm lens to us for examination and adjustment of the AF. Please return your camera and lens directly to Pentax Imaging Company at the address listed below for examination.”
When I will be back home from my work trip I will try the same scenarios with the K100D body I have to roll out a possiblity of lens issue. It’s embarrassing that using “few hundred $” equipment requires you to play tricks in order to get a perfect focus straight away.
Until this issue is done I am using high F stop in wide angle.
thaks for sharing the info with me
Ofer

Hi,

I'm using the K20D and the Sigma 18-50mm F2.8 Macro. The problem was exactly like yours and my other solution was to zoom out to 50mm, AF then zoom in to 18mm again.

David what type of camera and lens are you using?