If you want some lower back exercises with minimal risk and maximum control, try some bird dogs, supermans or unweighted extensions.
http://exrx.net/WeightExercises/ErectorSpinae/BWBirdDog.html
http://exrx.net/WeightExercises/ErectorSpinae/Superman.html
http://exrx.net/WeightExercises/ErectorSpinae/BWHyperextensionHips.html

Extensions can be tricky without something design to do them on: you can try lying face down on a bench, gripping it with your legs and hanging your torso as far out as balance allows.

All three can also be very good as static exercises, just hold as long as you can stand. Add tiny dumbbells / ankle weights if can hold it long enough to get bored 😉

Yes I was aware of those. I have lower back issues, so I don’t do either of those exercises right now. I am looking for a safe lower back exercise I can do that is minimal risk and the control I have over the weight is at a maximum. Some exercises are more dangerous than others, particularly without a spotter.

I have to think about it. Deadlift and squats are two execises you can do really wrong without noticing them and I have to make very sure people know how to do them right.

Place the dumbbells right before your feet and then do the same motion as with the barbell:

http://www.exrx.net/WeightExercises/ErectorSpinae/DBStraightLegDeadlift.html

Those are hard to find…