positional astronomy - SDSS: Inclination of a Field?

I am working with the Sloan Digital Sky Survey CasJob service.

I am trying to determine the ellipticity of a galaxy using the stokes parameters $U$ and $Q$ from which I can deduce $e$ and $phi$. But $phi$ is relative to the CCD chips. How can I get the real $phi$ (relative to the equator). If I am correct I would know the inclination if I knew what field the object is on and I knew the inclination of the field.

Each field belongs to a stripe. So I'm there if I know the inclination of the stripe? And How do I know the inclination of a stripe?

Is my problem realates with the column like phioffset_r described as Degrees to add to CCD-aligned angle to convert to E of N (I have no clue what this means)?

Note: I am not sure whether this is the right place for this question. Is there a better place?

Note 2: If this is the right place, then it would be nice if somebody could create the tag sloan-digital-sky-survey or SDSS. I could not figure out what existing tag would fit, so I did take positional-astronomy.