Does black backdrop have to be black, and white have to be white in portraits?

[indioli]

Ok, now I have only recently started to research portrait photography and start to play about with it... I have a friend who does portrait photography and she keeps telling me black has to be jet black, white has to be pure white, but i keep questioning this and seeing amazing photo's that don't follow these rules.
So anyone who can advise me, or give their opinion on this topic I would be grateful.

Also i have a pic, which to me is over exposed? But i don't want to put it on a forum because it wasnt taken by me so if i can send it to someone who works in portraiture, please let me know.
Many thanks!!

 

[tirediron]

Generally speaking if you're using a black or white backdrop, you will want them pure black or white, but anywhere else in an image, no; since pure black and pure white have no detail. With respect to the image, post a link to it in the thread, that will allow people to view it and not violate the TOS.

 

[KmH]

The background color I use the most for portraits is a medium gray. Specifically - Savage 107" x 12yds Seamless Background Paper 27-12 B&H

By using the right camera settings I can make that gray background look black, white, or by lighting it with gelled lights, many different pastel colors too.

With a black background you have to control where your lighting goes with flags, gobo's, barndoors, and other tools of the trade so it doesn't spill onto the background.

With a white background you have to be careful of light reflecting off the background to places you don't want it, like onto part of your subject.

 

[gsgary]

With only a white background, you can get white,grey and black from the one background
This was shot on a white background