I have created a slider with caption area on the right side. Every image on the slide contains "real" image - 623 px wide and the transparent area 307 px wide, which goes under the caption The problem is - there is a white line either at the right-most end of the slider or near the middle, at the beginning of the caption area.
Here is the image which shows how it looks like (I can't link to my site, because it is a development version, hosted on internal network):
As you can see, every browser is affected - most of them show white line at the right edge and Safari shows it in the middle. On a first glance, Internet Explorer renders the slider correctly, but on a closer look, it also shows vertical line in the middle - but noticeably thinner, so it is not visible in the image above. I did not modify the theme code in any way. All browsers are latest versions and I'm testing on Windows 7.
What is the best way to fix this? I tried to fill the right side of the image with the color of the caption background, but this did not remove the white line at the right edge.
The image itself is 930x360 px, just as the documentation asks.