To resolve this issue, you must export the PNG file from Photoshop again, or use the Microsoft Office
Picture toolbar to lighten or darken the image.
Method 1
- Inside your Office application, click the PNG to select it.
- If the Picture toolbar is not visible, point to Toolbars on the View menu, and make sure that Picture is selected.
- Use the More Brightness and Less Brightness buttons on the Picture toolbar to adjust the brightness of the PNG picture.
Method 2
The third-party products that are discussed in this article are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, regarding the performance or reliability of these products.
- Before you export the PNG file inside Adobe Photoshop, point to Color Settings on the File menu, then click RGB Setup.
- In the Gamma area, change the Gamma correction value to exactly half of the displayed value. Click OK.
- On the File menu, click Save Copy As, and then resave your PNG file with a new name. The new PNG will appear correctly in Microsoft Office.