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I am looking for to 'grey out' my image entirely - the main purpose is to be able to have high detailed picture and still allow me to read clearly written contents at the top of the image. The grey out filter/effect I am looking for looks like some web or app components background when a pop-up comes out. I am attaching an image showing you an example. I am a Photoshop user but can use something else if necessary. I have tried many filters but none has this disabled/grey mask effect.