CMYK for blue screen compositing

[lostbythelake]

Hi there everyone.

I had a few problems with my first posting, so I'm just bringing the issue back to the table.

I am currently trying to figure out the best CMYK defined colour of blue for compositing. From what I've been reading, it seems it doesn't really matter what colour of blue I use, provided the lighting is good and well balanced across the entire screen.

However, at the risk of sounding anal, I really would like to know the best colour possible. Would it be something as close to a true blue as possible, such as an RGB of (0, 0, 255)?

Thank you all for your time and consideration.

Cheers

 

[Kim Welch]

I apologize for the delay in responding, and thank you for posting. You've got the key point: even, well-separated lighting matters far more than the exact shade. For video, choose a blue or green made for chroma key, such as Rosco or Lastolite chroma fabrics or paint, rather than matching a CMYK print value. Keep your subject well away from the screen to avoid spill, and avoid that color in wardrobe. Most productions now use green because digital sensors capture more detail in the green channel.