Strange pattern in K20D Photos

<p>I just did a sunset to moonrise shoot. On downloading the images, some have a strange zigzag pattern on them. This is visible using LR 3.6, LR 4.1 RC and can be seen zooming in on the images on the camera's LCD. Anyone have any idea what this could be?<br>

Two 100% crops First without the pattern<br>

<img src="https://lh6.googleusercontent.com/-HJPCzMhdINw/T39KIKZaSTI/AAAAAAAACn8/vMQYbfhH74o/s853/20120406-_IGP8877-2.jpg" alt="" width="853" height="548" /><br>

2nd with the pattern<br>

<img src="https://lh4.googleusercontent.com/-81r0CJuLuHw/T39KIMdEI4I/AAAAAAAACn4/A0RufmWpTcI/s853/20120406-_IGP8878-2.jpg" alt="" width="853" height="548" /></p>

<p>Wouldn't have anything to do with whether or not that microwave was transmitting at the time you were taking the picture, would it? Just a guess.</p>

<p>I've just had a look through the photos and suspect that all those affected were taken using Live View (which I almost never do) with a Sigma 10-20. Other shots seem unaffected.</p>

 

<p>I think John has a point.</p>

<p>This is the result of RF interference. </p>

This makes sense. I was using Live

View because I had the camera at arms

length through a pallisade fence to

photograph the antennae at close

range.