Many times, the only way the public or potential clients can come face to face with your designs or projects is through photographs, photographs that capture the feeling and document the space the way its designer intended.
Photographing for interior designers and other types of designers (furniture, bathrooms, kitchens, etc.) requires getting up close and personal with the subjects, with narrower focal lengths as opposed to property or real estate photography where shooting wider is recommended - but not always beneficial.
A very big part of creating beautiful images is the use of artificial lighting. Natural light isn't always the best option to shoot with, and in some cases it's totally absent - this is where masterful use of artificial light steps in.
An immense amount of work, time and effort has gone into your designs, therefore photos that capture the beauty and functionality of your work are paramount when it comes to attracting new clients and creating effective marketing materials.