Need your idea

this photo was taken using my T3i and it seems the woman on the right is out of focus.
1/10
f1.4
iso 100

A couple of things come to mind. 1/10 for shutter speed is a little slow and could be contributing. The main reason is shooting at f1.4 - your dof is narrow.

D Thompson wrote in post #14113203
A couple of things come to mind. 1/10 for shutter speed is a little slow and could be contributing. The main reason is shooting at f1.4 - your dof is narrow.

thanks for the reply

Dennis is correct on both counts, your shutter speed is too slow, and your aperture too wide. You can fix this by upping your ISO from 100 to 400 (or even 800, depending on how good your camera is at that high iso). Once you've upped your ISO, your shutter speed will be faster, so you will be less likely to have motion blur. Then, bring your two subjects onto the same plane. You can see in this photo that one woman is slightly behind the other and when you have a very wide aperture that results in very little depth of field, one of the people is going to slightly out of focus because your camera can't focus on both faces at once. They need to be on the SAME PLANE if you have a wide aperture like 1.4. ONce you understand the exposure triangle, you will understand how to deal with these types of things, but that is the short and skinny version of what is wrong and how to fix it.