Black level & Screen Size - AVS Forum | Home Theater Discussions And Reviews
Forum Jump: 
Thread Tools
post #1 of 2 Old 11-28-2001, 01:06 PM - Thread Starter
jimki's Avatar
Join Date: Nov 2001
Posts: 1
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
If the black level is increased along with the increase in the projected image size, then at approx. what size does the need for a gray screen become unnecessary?
jimki is offline  
Sponsored Links
post #2 of 2 Old 11-29-2001, 06:31 AM
AVS Forum Special Member
KBK's Avatar
Join Date: Apr 2000
Location: The Wilds Of Canada
Posts: 6,660
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Liked: 13
The overall CR (contrast ratio) will be crushed as the screen gets bigger, and the eye will have less light to deal with per sq. foot of screen. The screen will require less grey in it, as the light output won't support the grey required to turn that 'grey level' to a 'black level'. Remember, the black level is mostly perceptive in nature,and has very much to do with:

1)ambient lighting,

2)contamination of the room from projected light from the screen,

3)reflection of light back on to the screen (from the room, or originally from the screen..getting back to it),

4)cross reflection on the screen surface itself,

5)reflective gain characteristics of the screen itself,

6)contrast ratio of the PJ itself.... and how linear that aspect is

7)max lumen count of the PJ in question

8) how many feet of screen you are using

9)YOUR eye's (not someone else's eyes!!) dilational (responsive) behavior to the given light situation.

10)and, of course, proper set-up of the above mentioned screen

11)Linearity of the internal components (in terms of Gamma, brightness, and contrast scaling...all rolled into the entire equation of your projector-eye-screen/type/design/greylevel -room-setup.

No simple answers there, but the criteria for getting the right screen should at least be known.

The perfect screen for a given situation, for a DIGITAL (ie, not perfect black level PJ type) projector is MUCH harder to get to than that of a CRT type. Each individual situation is different, and no one single screen design will do. Granted, some grey will help, the question is that.. how do you get to the perfect level of grey for your particular situation(so as to maximize the characteristics of your given PJ?

Answer: through experimentation, and understanding.

Ken Hotte

"Never forget that only dead fish swim with the stream." -- Malcolm Muggeridge.
KBK is offline  
Sponsored Links
Closed Thread Screens

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page

Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off