This is pretty great.
Lightroom works well for me, but editing is far from elegant. Lots of scrolling around on the tool pane, grabbing on-screen sliders, and making precise mouse adjustments can sometimes distract me from having a laser-like focus on the end result.
I found this bit of (currently free) software called
Knobroom that allows an external MIDI knob controller, typically used in music applications, to control Lightroom sliders. Knobroom was written for, and I currently use, the
Novation Nocturn, which is a USB device that is available for well under US$100.
(Other controllers can also be used, but I have only tried the Nocturn.)
The knobs on the Nocturn are of the "endless" rotary encoder variety, so there's no worry about the knobs being "out of sync" with slider positions. As you switch from photo to photo, the software takes care of it. You can set eight of the knobs on the Nocturn to control whatever eight Lightroom sliders you want, and you can set up multiple "pages" of controls to switch among using buttons on the device.
You can also map the buttons on the Nocturn unit to keystrokes, so you can perform a fair amount of navigating, tagging, and editing without ever using the mouse. (I like to use the buttons for some of the annoying multi-key combinations Lightroom uses, like Ctrl-Left/Right to navigate between photos on the filmstrip and Ctrl-Shift-C/V for copying and pasting settings.)
It only works on Lightroom 3.x for now, but the author is working on a version for 4.x.
The downsides, for me at least, are: (1) knob adjustments only start working AFTER Lightroom has totally finished loading an image, so there's a short delay when you switch from photo to photo (which I use to adjust crop via keyboard and mouse); and (2) every single knob adjustment ends up in your editing history, even consecutive adjustments of the same parameter in the same direction, so the undo/redo history can get cluttered. But these are pretty minor problems.
If you're still on Lightroom 3, check it out! Knobroom works on both Mac and Windows. (And for the true masochists out there, I can confirm that it runs under Windows 7 in a VMware virtual machine on a Linux host.)
Knobroom | Knobroom
Last edited by Quicksand; 07-18-2012 at 09:54 PM.