Options for manual camera controls on a phone app

I am making an advanced camera app for Android. Right now, I have come up with 2 ideas for implementing 3 manual controls (focus distance, sensor sensitivity, and exposure time) on a touch screen:

• Put one slider on the bottom edge of the display (would become the right edge on landscape), and put 3 buttons underneath it to change which setting the slider would change. The advantages of this method include eliminating the chance of accidentally moving another slider (more on that in the 2nd idea), and covering a smaller area of the viewport (it extends to the area behind this slider when the capture aspect ratio is wide).
• Put 3 sliders next to each other for each one of the settings. The advantages of this are being able to change different settings faster, but it allows changing the wrong setting accidentally as described before, and will cover up more area on the viewport.

Which one of those is better? Maybe there is a better implementation that I have not thought of.

EDIT: I did not mention that in both implementations, all values are visible at all times. They will be shown under their respective buttons or sliders.