(Intended audience: photographers)
Recently, I purchased a new tripod head with the hope it would increase my speed and accuracy when leveling my camera. (In real-estate photography, speed is important because I might have three dozen setups over the course of two hours.) The official name is Manfrotte 410 Junior Geared Head, which I purchased from Adorama as a used item. It's called a geared head because it has gears inside to adjust the camera rotation and front-to-back and side-to-side leveling.
Formerly, I used a ball-head tripod head, which required me to spend a lot of time adjusting the camera to make sure it was perfectly straight and level. Sometimes getting it perfect was tedious because a change in one dimension often required an adjustment in another, and I might go back and forth between two dimensions several times. Often, I gave up and decided to correct the leveling in software. That's not necessarily a bad way to do things, for the most part. However, sometimes doing the leveling in software means the photo will to be cropped by the software, which occasionally produces undesirable results when tolerances are close.
I'm delighted to report that the new geared head allows me to quickly set each dimension with a couple twists of the gear knobs. In fact, making the adjustments has actually been faster and easier than I had dared hope. I still double-check my vertical lines in my editing software, Adobe Lightroom, but I've noticed that Lightroom rarely needs to make any change.
One note here: when I'm leveling the camera, I make the adjustments based on the two-dimensional virtual horizon in my Nikon D750, not the bubble level on the tripod head. A bubble level just can't be as accurate as the precision system built into the camera. (And that's another reason I love my D750. It's a super camera for real-estate and architectural work.)
Of course, the new tripod head has a couple disadvantages. First, the geared head is heavier than the old ball head. Fortunately, the difference isn't so great that it discourages me from using it. I also use a Feisol carbon-fiber tripod that's fairly lightweight, and the combination with my D750 still makes for a system that's not overly heavy.
The second disadvantage is closely related to the first. The plate for attaching the camera to the tripod head is unnecessarily big. All of my other head plates, both Manfrotto and Arca-Swiss types, aren't nearly as large. Manfrotto could reduce the head's weight several ounces by incorporating one of their smaller plates, which many photographers probably already own.
In summary, I'm very happy with my new tripod head. Manfrotto makes several geared heads that seem very similar to one another, and I had difficulty choosing one. However, the 410 Junior suits my needs very well, and I would recommend it to other real-estate and architectural photographers.