February 12, 2009
Scrubby sliders & more
You may well know about "scrubby sliders" in Photoshop–the little finger-with-arrows icon you get when your cursor hovers over the label next to a numerical field, such as "Opacity" on the Layers panel. (Here’s a screenshot borrowed from Photoshop Essentials.) With scrubby sliders you can click and drag on the text label, moving left and right to adjust the field’s value up and down. You may not have discovered a couple of nuances, however:
- Holding Opt/Alt while scrubbing makes the values change 10x more slowly. This is great for fine-tuning a value. Conversely, holding Shift while scrubbing makes the values change 10x faster. This is great for making an audience sick while demoing canvas rotation. (Open a really big image, zoom out, hit R, and then Shift-drag over the Rotation Angle text on the Options Bar. Entreat your viewers to stare at the center. Watch them become your willing thralls…)
- Some fields don’t have text label next to them, and it therefore seems that you can’t use scrubby sliders with them. Ah, but that’s where holding down Cmd/Ctrl while mousing over the field comes into play. By holding the modifier while dragging, you can use a scrubby slider on these fields. (Adding Opt/Alt or Shift works as you’d expect.)
On a related note, when you put focus on a text field in Photoshop, you can nudge its value up and down by using the up/down arrow keys. Holding Shift while arrowing naturally makes the increment of change 10x larger.
It’s all these little custom behaviors that help make moving Photoshop from Carbon to Cocoa a rather involved affair. The app has developed a lot of little tweaks (e.g. holding down Opt/Alt in dialog boxes to turn Cancel into Reset) that don’t just come along for free. It’s also an illustration of why custom widgets are sometimes desirable. I’d like to see Photoshop and other CS apps make scrubby sliders much more universal/discoverable via something like the Adobe video apps’ sliders (screenshot). [Update: See also the ones in Flash CS4.]
There’s one other related thing, which I hate to mention as it’s a bug, but I can offer a solution. In CS4 if you click on a text label to highlight a field, then use a mouse wheel to adjust values, you may notice that the field stops changing. The workaround is to keep your cursor over the text label, or anywhere outside the field itself. Sorry about that rough edge.