What kind of photographs do casting directors and agents actually require?
At the start of your acting/ model career a portfolio book is essential and the amount of options open to you are vast when it come to photography. Many actors starting out will have an wide array of studio photography commissioned in a wide range of poses, clothes, styles etc - this is a common mistake and not required. A more experienced actor will have a bigger portfolio book due to their time in the industry and represents the work done but as a new entrant you cannot be expected to have this.
The most useful pictures you can have done for an agent or casting director as ones that show you in various way including close ups, full length, looking to camera, looking off camera and colour/ black and white.
As a photographer in berkshire, I recently worked with a Alex from The Reel Scene (a school for actors in Maidenhead) to show the type and style of photography that is of most use when sending your portfolio off to agents. Alex's advice was to show a variety of style but to keep it honest and 'the real you' as agents and casting directors will see straight through too much photoshop or post production work.
So you need to be clear to the photographer of exactly what you require - so either get some advice from a professional (e.g. someone like The Reel Scene) or simply look through articles in the press/ internet for ideas of poses, clothing, make up etc. It can be a good idea to practice your poses at home and get a friend to comment on the results or bring example of the type of pose you want to achieve with you to the shoot.
If you are in need for any portfolio photography then please don't hesitate to get in touch