Diagonal bar across upper right corner of pictures at certain focal lengths

Mechele1964

I'm very new at this, and I'm not sure what has happened. There's a diagonal bar across the upper right corner of pictures at certain focal lengths. I'm not even sure I'm describing this well.

mikejduk

Could it by any chance be the Lens hood? When a lens hood is attached you are in danger of getting a vignette or hood shadow at certain focal lengths.