If you find an image for your presentation which doesn’t quite match the overall colour theme, you can use Microsoft recolouring tools to change the look into greyscale with a few clicks.
1.Open PowerPoint or Microsoft Word and insert or select the image you want to change. The Picture Tools contextual tab should become visible.
2.The Format tools in the Adjust group can quickly change the way the images look. Click the Colour button.
By changing the colour saturation the image will increase or decrease the intensity of the colour. Select the first icon to remove all colour and bring the saturation to 0%.
By selecting a colour tone option, this will adjust the colour temperature of the image. The recolour options will apply a colour cast over the image. The colours available are determined by the defined colour pallet, but you can manually select a colour by the More Variations button.