Videokarma.org

Go Back   Videokarma.org TV - Video - Vintage Television & Radio Forums > Early Color Television

Notices

We appreciate your help

in keeping this site going.
Reply
 
Thread Tools Display Modes
  #1  
Old 08-22-2023, 05:33 PM
timmy's Avatar
timmy timmy is offline
VideoKarma Member
 
Join Date: Jan 2011
Location: Delaware ny
Posts: 3,708
Why is it some colors are alittle bit different from a flat tv to a crt tv
Reply With Quote
  #2  
Old 08-22-2023, 08:36 PM
Yamamaya42's Avatar
Yamamaya42 Yamamaya42 is offline
VideoKarma Member
 
Join Date: Nov 2018
Location: Round Rock TX
Posts: 3,177
Quote:
Originally Posted by timmy View Post
Why is it some colors are alittle bit different from a flat tv to a crt tv
NTSC= Never Twice the Same Color.
__________________
=^-^=
Yasashii yoru ni hitori utau uta. Asu wa kimi to utaou. Yume no tsubasa ni notte.
いとおしい人のために
Reply With Quote
  #3  
Old 08-22-2023, 08:37 PM
old_tv_nut's Avatar
old_tv_nut old_tv_nut is offline
See yourself on Color TV!
 
Join Date: Jul 2004
Location: Rancho Sahuarita
Posts: 7,747
Quote:
Originally Posted by timmy View Post
Why is it some colors are alittle bit different from a flat tv to a crt tv
Multiple reasons.

1) The picture tube primary colors (phosphors) were changed over time from the original NTSC standards to get brighter pictures (the green saw the largest changes, but blue changed significantly also. The red changed slightly; the strongest change was toward orange in the all-sulfide tubes.
2) TV manufacturers made proprietary changes to the color circuits to partially compensate for the phosphor changes
3) TVs for a long time used a quite cyan white balance, to reduce the load on the red electron gun, due to the relative inefficiency of red phospors
4) meanwhile, TV cameras were designed to make good pictures with the newer phosphors, so there were two rather uncontrolled adjustments in the system, at the camera and in the receiver.

5) Finally! PAL and HDTV settled on the correct circuitry in cameras and receivers for the new phosphors, which also became the sRGB standard for computer images (jpg files).
__________________
www.bretl.com
Old TV literature, New York World's Fair, and other miscellany
Reply With Quote
  #4  
Old 08-23-2023, 04:40 AM
timmy's Avatar
timmy timmy is offline
VideoKarma Member
 
Join Date: Jan 2011
Location: Delaware ny
Posts: 3,708
Quote:
Originally Posted by old_tv_nut View Post
Multiple reasons.

1) The picture tube primary colors (phosphors) were changed over time from the original NTSC standards to get brighter pictures (the green saw the largest changes, but blue changed significantly also. The red changed slightly; the strongest change was toward orange in the all-sulfide tubes.
2) TV manufacturers made proprietary changes to the color circuits to partially compensate for the phosphor changes
3) TVs for a long time used a quite cyan white balance, to reduce the load on the red electron gun, due to the relative inefficiency of red phospors
4) meanwhile, TV cameras were designed to make good pictures with the newer phosphors, so there were two rather uncontrolled adjustments in the system, at the camera and in the receiver.

5) Finally! PAL and HDTV settled on the correct circuitry in cameras and receivers for the new phosphors, which also became the sRGB standard for computer images (jpg files).
Interesting , lots of changes just for tv.
Reply With Quote
Reply


Thread Tools
Display Modes

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

Forum Jump


All times are GMT -5. The time now is 08:46 PM.



Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2026, Jelsoft Enterprises Ltd.
©Copyright 2012 VideoKarma.org, All rights reserved.