Anyone who deals with the topic of “compositing” or combining photos must inevitably deal more or less with light. Specifically, when for e.g you’d like to make a person shot at a different time to a background fit in perfectly.
Here is an example of how it can look like this:
The model photo in this picture was taken in the studio and then placed into the scene. It sounds simple – and it is…. When you pay attention to a few things.
In this tutorial, we have broken the picture down into everything you should know about perspectives, shadows, tips and tricks required in order to achieve this level of compositing.
Lighting can be difficult so I wanted to write something about it below.
If you are planning a compositing, you should choose the background BEFORE shooting the model. This is the most common mistake and it will remove a lot of problems before they are even created.
If you know what background you want to use, you can “read” / “see” the light before you hit the studio and can recreate it with much more ease!
In the example above, this was quite simple. The light comes from the left (indirectly / bounced), so it is very soft and diffused. In the studio, a large light source was used, which radiates from left to the model.
The light fall off is not particularly quick here, so the light source was placed relatively far away (read up on the Square Inverse Law) – but this makes the light harder as it’s now a smaller light source in relation to the model.
A simple trick (at least for those with white walls) is this, flash te wall and bounce off to the model:
Flashed the wall and all of a sudden you have a HUGE light source – the farther you go away from the wall, the softer the light becomes. In the background, which takes place on a cloudy day outside, I also like to flash the ceiling – this way light is coming from the front and above.
This is what you need to consider first:
Where does the light come from?
Correspondingly, I have to place the light source and lighting against the ceiling, wall or even the floor.
How quickly does the light fall off?
The faster light falls off I need, the closer the model and wall have to be together.
How soft is my light?
The softer the light, the farther the flash must be from the wall.
The background gives the perspective ( you can pick those up in the blog store). You have to take this background into account when shooting.
However, it is difficult to determine the perspective of the model afterward since the cluesand environmental cues are missing. Again, there is a trick that is quite simple we can use to help us:
Glue some parallel stripes with tape to the floor. Depending on the camera height, they then run more or less parallel and result in the extended view my vanishing point. Use this to match it to the background perspective and dictate camera height.
Make sure that things you want to place on the left are also on the left side of the picture. The perspective changes not only from top to bottom but also from left to right!
White, Gray, Green or Black?
What is the best color for the background? This question is not easy to answer. The hardcore compositors swear on Gray, though I use white. Why?
Gray can be superimposed wonderfully – that is why this is the first choice for many. But the problem is that you cannot illuminate grey evenly with as much ease as white. Meaning you’d need more gear and a bigger space to be able to get an even fall off of light.
Film / “specialists” work with green – a procedure that makes sense in the film. The film-effect people have to deal with 25 pictures a second – we have not. But for us photographers, we prefer not have a colorpill in the picture. Colorspill is incidentally an irradiation from the background – slight green discolorations, which is difficult to remove from skin later on. I think green is stupid. Probably because I do not like football so much.
So stay black and white.
Black is great for textures and I use fabric backgrounds that really swallow any residual light so you get really black backgrounds in the picture. With compositing pictures there is the danger that image areas in the black “drown”, or under expose, and thus merge with the background. This is difficult to fix in Photoshop.
White is great. If no light falls on a white background, it is also black. If some light falls on it, it becomes gray and when a lot of light falls on it, it burns out and becomes completely white.
If you are using channels, and I am, because I like channels for selection and masking, the channel is completely filled when using white.
For the lighting I have been using two strip lights lately – it is very important that these are just behind the model. As far away from the back wall as possible. You get a nice silhouette of the model and a uniform background. I’m trying to keep the RGB value of the area between 230 and 240, so I can be sure that nothing burns out.
Very important: The model must not be too light – check the edges on light clothing for possible fusing with the background. This must never happen.
This is my basis for a clean example. As needed, I can now light the model. Either over the ceiling or the wall or with different light sources. The lighting situation of the background determines the setup.
Here, for example, I used a normal reflector with an orange color gel to simulate the sun below:
The finished picture looks like this:
So that’s how to shoot a model for compositing in a nutshell – if you take these tips to heart, little can go wrong!