Decide on camera position.
When photographing an interior, do you do that with the eyes of the visitor or user of a space or the designer? A designer may want you to give an overview of the interior to enable him to explain the layout of the place. The camera standpoint is that much higher than that of a visitor. For a good coverage you may want to do both.
When positioning the camera, use a sturdy tripod with good leveling possibilities. You will find that the so called ‘ball-head’ tripods used for flexible positioning are far from ideal for this type of work. Better is to use a tripod head where you can adjust every dimension independently. The build-in leveling device will give you a good starting point. Look for walking patterns and view lines in the interior. Make sure that the vertical lines remain vertical, in a way that walls don’t fall and furniture doesn’t look pear shaped. Try to realise that when transforming a 3-dimensional space into a flat 2 dimensional image, the picture needs to be pleasing to the eye. So look for classic diagonal view lines and try to implement the rule of thirds. Subsequently look for horizontal lines in relation to the frame of the picture. If the horizontal lines are level with the picture frame than this would be perfect. Don’t forget that any correction of vertical and horizontal perspective in post-processing will eat into the overall resolution of your image. The use of wide angle tilt-shift lenses will make live easier and gives you more flexibility in choosing your position. Also live view is a very necessary feature of your camera with this type of photography attached to a laptop or tablet computer. In the olden days, analogue photographers took these images with large bulky technical view camera’s and had to judge the ‘preview’ upside down covered with a black sheet… Although I am not that old I used to work with them when I studied photography that the Academy of Art in Groningen.
Exposure and contrast
The wide angle lens and tripod enables for great depth of focus by using small apertures. For a 17-24mm lens for a full-frame camera, use f8-f16 for the sharpest images at iso 50-200. Use a remote control or the timer to avoid any camera shake.
You will find huge differences between the lighter and darker area’s of an interior, especially when bright daylight is coming in. If you use the centre weighted average or evaluative exposure mode of the camera the white walls and ceilings will look dull and grey and the shadow area’s will lose detail and colour. A simple way to overcome this is over-exposing the image and darken certain area’s in post processing by ways of dodging and burning. The success rate of this way will depend on the contrast, exposure and the dynamic range of your sensor. Better is to use a combination of analogue techniques and digital contrast enhancement in post-processing.
By adding light to the darker area’s the overall contrast will decrease and colour and clarity will return in the shadow area’s. Obviously, this needs to be done in a subtle way so that the natural atmosphere of the space is not changed.
Another way is combining multiple exposures in Photoshop. Do this by adjusting the exposure time and take 3-6 exposures depending of the overall contrast. Make sure that the camera doesn’t change position during the exposures and that there are no moving subjects in the image. There are various automated ‘HDR’ type software methods to combine these images automatically, but I find that the end result tends to look very artificial. I use a manual method called DRI, or Dynamic Range Increase in Photoshop. I start with the one or two stops over exposed image and then put the darker ones in layers over each other, by selecting the highlights and masking them. This will take a bit of practice, but you will get very natural results!
Obviously in some situations you can combine the two above described methods.
Colour temperature differences
An interior will have a wide variety of light sources. Fluorescent will generate a green-ish image, whereas tungsten will make the surrounding area of the light source brown-red. Incoming daylight contains a lot of blue light and the flash light as well. It is therefore crucial that you adjust the whitebalance of your camera as accurate as possible using live view and some careful interpretation as it is impossible to remember how it was when you are sitting behind your monitor.
Usually the colour balance will lean towards tungsten and the camera should be set somewhere in the region of 3000 – 4000 Kelvin. Some partial editing will be needed to certain area’s to bring these within an acceptable level. Usually the blue effect of daylight is accepted and very much liked in the interiors industry because of the high tech stage light effect.