How to get pure white backgrounds
Give studio shots the professional look with Lightroom’s new masking tools
The white background – a must for LinkedIn headshots and Amazon products – is a Holy Grail for new studio photographers. Lighting a background to pure white in the studio, though, can mean that the background itself becomes a light source. You can get blowback, where the edges of your subject fade into white and lose all edge detail. It takes time to perfect – and when you’ve a lot of headshots or products to shoot, that can mean a lot of additional work. Fortunately, Lightroom’s new Masking tool can help.
For the best results, use a white background and position the subject close to it. You may perceive the background as white at this point, but really it’s light grey – and your aim is pure white. Use a soft light for the subject, but try to avoid having too much visible shadow.
Generally speaking, you should do the bulk of your colour and tonal edits before tackling the masking, as this is the order in which Lightroom processes the file.
Create a mask
Under the Histogram, click on the Masking icon (the dashed circle). While you want to mask the background, you need to first select the subject. Click Select Subject. Lightroom will use AI to find the subject (quite accurately) and show it covered by a mask. You may want to use the ‘Show Overlay’ swatch to change the default mask colour, to check the selection is accurate.
Invert the mask
The Select Subject Mask shows as a component of Mask 1. To the right of the name is an ellipsis. Click this to reveal a menu. From this menu, choose Invert. This swaps the mask from the subject to the background.
Bleach the background
With the background selected, press J to toggle the clipping indicators on. Areas of pure white will now show as red, making them easier to spot. Use a combination of Exposure and Whites to make the entire background go red.
Adjust the effect
Sometimes lightening the background can remove things like hair detail. Click on the ellipsis again and choose ‘Intersect Mask With’, then select Luminance Range. Drag the left arrow in until you see grey appear. Then drag it back. A handle appears, and the gap between the handle and the arrow allows you to feather the mask edge.