Considerations for Composite Photography

If you are attempting a realistic product composite, the image you choose as your primary background will have a huge effect on how the product will be shown. Choosing a suitable image can save you time in the shoot and a lot of time retouching. So here are a few things to consider when looking for an image.

Be selective

Consider how the image will inform the perspective, scale, lighting and colour of the product being added to it. Will the lighting show product well? Does the image have sufficient depth of field? Is the light source obvious and are you able to re-create it? What surface will the product sit on? And does the overall feel of the image match the aspirations of the target market?

Consider resolution and aspect ratio

If the final composite is going to be printed at a large size, or used in a portrait orientation, your choice of image should account for the required resolution and ratio. If the image will have multiple uses, try to account for the most demanding use.

Look at the metadata

Once you have chosen your starting image, look at the metadata (if it has any) and try and determine sensor size, focal length, shutter speed, aperture and ISO. All these parameters will inform you how best to convincingly match your shot with the found image.

Look for the horizon

By establishing where the horizon line is within your image you can match the vanishing points of the product you are adding to it with those already in the scene.

You can find the horizon line by following parallel lines until they meet. This often involves extending the images canvas in your image editor, then drawing lines that originate from objects in the scene. Images may have more than one vanishing point. For example if you’re photographing the corner of a building and can see two of its sides there will be two vanishing points.

The horizon is then drawn across where those vanishing points meet. You now have the beginning of a perspective grid. The horizon can tell you a few useful things about the image. If the horizon falls below the middle of your image the lens was likely pointing down on the subject. And if the horizon is towards the top of the image the camera was likely pointing up at the subject. In practical terms, if you can see the top of objects e.g. the roof of a car, either the horizon line will be below the centre of the frame or the camera height has been raised.

Having chosen the background image carefully and examined its characteristics, we now have a good idea of the lighting and angle we need to shoot the product at to match.

Tips on matching the angle

If you are shooting tethered with Capture One you can overlay a reference image (the perspective grid you have already created) to check the angle. A similar technique is described on the Capture One blog.

Alternatively, if your camera has an inbuilt multiple exposure mode you can also use this to align the angle of the surface you are photographing. First take an image of your perspective grid on a black background (by photographing your computer screen) then match the lines of that grid to the surface the product is on (the black will become transparent leaving only the reference lines). 

Matching the surface

If the surface you are going to be placing the product on is reflective, or has noticeable shadows, trying to approximately match the reflectivity and texture can go along way towards making the product feel convincingly grounded. 

Matching the lighting

By studying the background image you should have a good idea about the direction, intensity and colour of the light you are trying to mimic. Consider the scale of the product, if it’s small you can replicate a larger light source in the scene by bringing the light closer to the product.

Making it easy to cutout

To make things easier when it comes to editing, having a background that is in contrast to the product will help to speed up the cutout process. Alternatively, you can use a green screen setup.

When it comes to the edit, you start by cutting out the product, remembering to leave any shadows or reflections needed. You then find the vanishing point(s) of the product using the same process as earlier. This will give you reference points to place on the horizon line of your background image. Now you can scale and move the product anywhere along that horizon and the perspective will match. Any colour and contrast tweaks can then be made to help the product blend in. Using these techniques should help take some of the guesswork out of your next composite.