• Please use real names.

    Greetings to all who have registered to OPF and those guests taking a look around. Please use real names. Registrations with fictitious names will not be processed. REAL NAMES ONLY will be processed

    Firstname Lastname

    Register

    We are a courteous and supportive community. No need to hide behind an alia. If you have a genuine need for privacy/secrecy then let me know!
  • Welcome to the new site. Here's a thread about the update where you can post your feedback, ask questions or spot those nasty bugs!

Lighting in the color balancing suite

Doug Kerr

Well-known member
In a recent post in another thread, I had commented on Asher's saying that when doing color balancing and such he used a "dim" environment. I had remarked that I seemed to remember that the "recommendation" for surround illuminance (let be return shortly to that term) was not what I would consider "dim".

Let me first say that the various recommendations and practices in this regard do not deal with the illuminance on the work area but rather with the luminance of surrounding objects (the desktop, the walls, and so forth). My error in mischaracterizing the property of interest.

As I did some further researcher, I came across a very interesting section in Alexis Van Hurkman's substantial book, "Color Correction Handbook: Professional Techniques for Video and Cinema". Rather than quote it at length, I give this link, which should take one to the section to which I refer:

https://books.google.com/books?id=k...onepage&q="display surround lighting"&f=false

(although the larger section of this section is a part, "Setting up a Color Correction Suite", beginning on page 60, is valuable overall).

Of course the context of this work is TV and video cinema processing, where different considerations and criteria may apply from those of interest to us, working on "still" images.

Nevertheless, I find this very telling. Hurkman describes in some detail the published norms for the luminance of the area surrounding the image monitor, but then concludes by saying, in effect, all this notwithstanding, many professional facilities doing color balancing for HD video operate in environments where the surround luminance is at a very low level (about 1% of the display luminance for reference white).

Curiously enough, Hurkman recommends that one be prepared to make measurements in this connection with a spot photometer "capable of measuring intensity and luminance in foot-lamberts (Ft-L) and lux." Firstly, intensity in its formal sense (luminous intensity, to be complete) is not really a photometric quantity of any interest in this matter (although it is often used in a very vague, general sense for various kinds of photometric "potency"). Secondly, while the foot-lambert is a unit of luminance, the lux is a unit of illuminance.

Best regards,

Doug
 
Top