When I take portraits of my clients in the studio, I often end up with a grey background. Most of the time it is a white background, that I make light or medium grey depending on the subject and what I want to achieve, just by letting the right amount of light reach the background. But sometimes, background colour makes it a better portrait.
Changing background colour, or rather, adding, can be really really simple (just use the Adjustment Brush in Lightroom) if the portrait is lit in a way that takes away most of the hurdles when it comes to making the transition between the subject and the background look natural. Or natural enough for a studio portrait like this.
Behind the scenes, rim lights
What makes this type of lighting setup so easy to work with when wanting to change the background colour is that it creates a border around the outlines of the subject. Without the border, the transition between, for example, a blue shirt and a grey background would contain so many pixels with mixed colours that would be hard to get right. Blonde hair and woolen clothing can also be really tricky.
The rim lights
To get a hard rim light on both sides, I used two Profoto D1 500 with the new Zoom Reflector from behind. I still only have a grid for one of them, so I had to use black flags standing on both sides of my model.
They serve two purposes; one is to block light from behind hitting the lens, and the other is to enhance the contrast on the sides of his face. I use that technique often as I have a small studio and light can bounce around quite much if you don’t stop it.
When you have a lighting setup like this, you can easily change the background colour just by using the Adjustment Brush in Lightroom.
Auto Mask works
I start by using it with the Auto Mask feature turned on, and a large brush to quickly cover most of the background. Working my way closer to the outline, I shrink the brush size so it fits around the details.
After the quick mask is set, I switch to Erase and paint over parts inside the mask that I don’t want to change the colour of.
For parts of the hair I can allow myself to let the background colour shine through, I think it looks ok if it blends a bit from blown-out white to the background colour.
When I am finished with the mask, I just add colour, experiment a bit with Temp, Tint and Saturation to get the colour I want.
Faking a gradient background
If you want a gradient background, the best way is to do it natural with a light, but by changing Highlights, Contrast, Shadows and Clarity together with Post-Crop Vignetting in small amounts, you can create it from a relatively flat lit background. Doing all this in Photoshop would of course be a lot easier in many ways, but you can get a long way by just using Lightroom 4.
Hair light for some hair colour
If my model this day would have been blonde, I might have needed a hair light to make the light border go all around the outline. But, with darker hair it is easy to make it look ok on the top of the head just like this.
For these portraits, I let the rim light be really hard and blow out all the details in some parts of the photo. You can make it softer and still use the same technique, but there will be more work making the transitions look good if there are details left.
One thing that can make the changing of background colour easier if you don’t want this hard rim light look is to use a background light with a gel that is close to the colour you want it to be. Just by having a slightly blue or yellow background will make it easier just to enhance that colour later or, the transitions are already in the same part of the colour scale.
For this setup, I used three Profoto D1 (two 500 and one 250 Air), and could have added another for hair light or background light. If you only have three lights, you could shoot the background separately. Just remove the model, point one of the lights (or more) at the background to get the pattern or gradient you want.
With this type of lighting, adding a background is as easy as this, but that would require Photoshop I guess as Lightroom doesn’t handle layers.
So, if you want to save money by not buying background paper in different colours, this might be a way of getting portraits with any background colour you like. I feel I need to get away from producing too many portraits with only grey background, and using gels to get the colour I want takes a lot of time to get right.