Quote Originally Posted by Worker 11811 View Post
It gets so bad, some times, I have to keep a ruler on the bench next to my enlarger to help me line up the images on the easel.

Okay... Now, it has a name. That still doesn't make my pictures come out straight.
A tripod is invaluable in the field. Coupled with a spirit level, it is a big help in getting horizons level. A grid in the focusing sceen is another useful aid, the next step up is a full size viewscreen (I love the view on my Wista ).

In the darkroom, a decent square along with the ruler are essential tools.