I've turned something on and it's doing my head in. Whenever I try to move text, or a layer within the document, Photoshop moves the background layer and replaces it with a bright red colour.
Occasionally the entire image also goes bright red. It's like an 80% opacity so I can see the layers underneath.
Does anyone know what I have done here? and how to set it back?
Please post a screenshot of your entire Photoshop window
Quick Mask is turned on. "Quick Mask" appears in your document's title tab.
Quick Mask uses a red overlay to indicate areas out of a selection. It's like the red film (rubylith) used to mask off areas of artwork in olden days of pre-press.
Press Q on your keyboard to toggle it off.