Photoshop CS6 stand alone issue

[CharlyIBC]

I am using Mac OS Mojave. When I open Edit > Convert to Profile, the Use Dither checkbox is grayed out. It was checked previously, but today it's unchecked and grayed out.

What would cause that? And how can I fix it? Thanks!

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[Jeff Arola · Accepted solution]

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(Image>Mode)

From the photoshop help manual:

https://helpx.adobe.com/photoshop/using/color-settings.html

"Use Dither (Photoshop) Controls whether to dither colors when converting 8‑bit-per-channel images between color spaces. When the Use Dither option is selected, Photoshop mixes colors in the destination color space to simulate a missing color that existed in the source space. Although dithering helps to reduce the blocky or banded appearance of an image, it may also result in larger file sizes when images are compressed for web use."

[CharlyIBC]

Thanks Jeff! For whatever reason when I switched to Mojave it seems to have changed the settings in Lr 4 to 16 bit, as I never has this happen before.