It's off just enough to be noticeable. If you use PS
, you can use the ruler tool (it lives underneath the eyedropper in the tool palette) to draw a ruler line. I drew it on the horizontal edge of the helipad. When you do that, then go to the Image > Rotate Canvas > Arbitrary... and it will automatically fill in the degrees and direction to level it to where you drew the ruler line.
In this case, .7 degrees CCW.
The skids aren't parallel to the imager, so I wouldn't use those to level in this case.
Also, if you turn the rulers on in the View menu, you can drag guides from the horizontal or vertical rulers and place these guides along verticals or horizontals to gauge their straightness. These help to judge levelness as well.
[Edited 2007-10-26 08:06:18]