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Adjust Exposure for HDR images

The Exposure adjustment is designed for making tonal adjustments to HDR images, but it works with 8‑bit and 16‑bit images. Exposure works by performing calculations in a linear color space (gamma 1.0) rather than the current color space.

  1. Do one of the following:

    • Click the Exposure icon  or an Exposure preset in the Adjustments panel.

    • Choose Layer > New Adjustment Layer > Exposure.

    Note: You can also choose Image > Adjustments > Exposure. But keep in mind that this method makes direct adjustments to the image layer and discards image information. Adjustment layers for 32-bit images are available in Photoshop Extended only.
  2. In the Adjustments panel, set any of the following options:
    Exposure
    Adjusts the highlight end of the tonal scale with minimal effect in the extreme shadows.

    Offset
    Darkens the shadows and midtones with minimal effect on the highlights.

    Gamma
    Adjusts the image gamma, using a simple power function. Negative values are mirrored around zero (that is, they remain negative but still get adjusted as if they are positive).

    The eyedroppers adjust the luminance values of images (unlike the Levels eyedroppers that affect all color channels).

    • The Set Black Point eyedropper sets the Offset, shifting the pixel you click to zero.

    • The Set White Point eyedropper sets the Exposure, shifting the point you click to white (1.0 for HDR images).

    • The Midtone eyedropper sets the Exposure, making the value you click middle gray.