Clamp Colors in Photoshop 32 bit float Color Depth

Photoshop CC 2018

Photoshop CC 32 bit float linear workflow is developing nicely but it still lack some needed basic components, and one of them is a Clamp Color Adjustment, equivalent to a node you will find in any 32 bit float HDR capable compositing software.

Clamping the colors means limiting the britest values to set values, usually 1.0 – white and 0.0 – black, so that no pixels will have higher than white or lower than black (negative) values that can create unwanted results in further operations.

* Brighter than white (super-whites) and negative colors are a feature, and part of linear 32 bit float color processing.

* If there is such an option that I didn’t find please let me know..

In order to clamp the layers colors we convert it to a Smart Object, and convert its color depth to 16Bit internally, so the individual layer gets clamped but the main document remains 32Bit float unclamped (HDR).

To clamp the colors of a layer:

  1. Convert the layer or layers to a Smart Object.
  2. Enter the Smart Object for editing.
  3. From the Image > Mode  menu, choose 16Bits/Channel,
    And in the Conversion dialog that opens choose ‘Don’t Merge’, or choose Merge and then in the HDR Toning dialog choose Exposure And Gamma mode to keep the image unchanged.
    The conversion to 16Bit color depth without Merging or Merging using default Exposure and Gamma mode will clamp the colors.
  4. Save the Smart Object.
  5. Return to the main document, the layers colors are now clamped.


Photoshop Smart Objects

Photoshop CC 2018

Smart Objects are Photoshop’s non-destructive compositing / Processing functionality.
Smart Objects allow you to encapsulate (nest) layers and adjustments into a “sub-Photoshop documents” (composites in compositing terms) that have their resulting image as one layer in the main document or the Smart Object that contains them.

For example resizing a Smart Object layer doesn’t change or throw away it’s original pixels (no destructive re-sampling of the layer)

Another feature of Smart Objects is the ability to apply Smart Filters that can be changed or deleted or applied selectively using masks.

* Smart Object layers are marked with a Smart Object icon

* Images dragged into a Photoshop document are created as Smart Objects By default.

* Working with a lot of nested Smart Objects can be memory demandng and also consume scratch disk space with temporary files.

Create a Smart Object:
Right click the name of a layer or layers and choose Create Smart Object.


Edit the Contents Of a Smart Object:
Right click the name of a Smart Object Layer and choose Edit Contents,
Or double click the Smart Object icon in the layer icon.
* Photoshop Smart Objects open for editing as an independent Photoshop document in a new Tab. once saved, the document containing them will be updated.

Convert the Smart Object layer to a regular layer:
Right click the name of a Smart Object Layer and choose Rasterize Layer.
* This will lose all the internal layers and effects and keep only the resulting layer.

Smart Object Operations: