How to communicate with colorist?

The best way to communicate to any colorist is visual references. It can be sending a reference movies or stills. It can save lot of studio time between the director, director of photography and colorist. There are many ways to interpret a scene and color it.

Do I have to shoot in raw/log to color grade?

If you have not shot your film yet make sure you shoot in highest quality possible. It means you shoot in RAW and LOG color space to give the most flexibility to the colorist. If a colorist does not have a good source it will limit colorist to develop specific look for your project.

Do I have to do look development test before shoot?

If you can shoot a test footage in similar lighting condition and work together with the colorist for the final look development you can make informed decisions in lighting, wardrobe, set design, color and mood that you want to create. It will eventally result in better result of the project.

How long will it take to grade a project?

Once the colorist gets the project they're going to need time to go through each shot. Color grade is one of the last process in filmmaking. Please consider enough time to actually sit through all the details during that creative process because this really is polishing of your final film. Colorist job is to create consistency across different shots, create a cinematic look that conveys emotion and disappers on screen. Remember, you need time for revisions.