Today’s Question: I know you are supposed to be able to set the black and white points for an image in Photoshop using Curves, but the sliders below the histogram have disappeared. Has this feature been removed, or did I do something wrong to cause them to be hidden? Can I get them back?!
Tim’s Quick Answer: It sounds like you have simply activated the “pencil” tool within the Curves adjustment. Simply switch to the “anchor point” mode and the sliders for the black and white point adjustments will appear again.
More Detail: The “pencil” tool for the Curves adjustment can be activated by clicking on the pencil icon, which can be found among the vertical column of icons to the left of the histogram display on the Properties panel. With the pencil tool activated you can draw a free form shape for the Curves adjustment. This can be helpful for fine-tuning your adjustment when the shape of the curve hasn’t gone exactly according to plan.
When you are in the “pencil” mode, you won’t see the sliders for the black and white point (nor actual values for the Input and Output options below the histogram). However, if you switch back to “anchor point” mode, you’ll get those controls back. To return to the anchor point mode, click the button directly above the pencil icon among the vertical column of icons to the left of the histogram on the Properties panel.
As a general rule I prefer to work with the anchor point mode for the Curves adjustment. However, from time to time it can be very helpful to switch to the pencil mode to cleanup the shape of the curve. You can also click the “smooth” button below the pencil icon to smooth out any rough corners you drew on the curve with the pencil tool.
Even after working with the pencil feature, however, I will generally switch back to the anchor point mode to finalize the overall shape of the curve for the Curves adjustment for an image. But perhaps most importantly in the context of today’s question, the black and white point sliders that disappear when you’re working in the pencil mode will return when you return to the anchor point mode for a Curves adjustment.