Jesse Clift
Agent
- Joined
- Jul 30, 2000
- Messages
- 44
Hello all,
I am having a serious problem with my Akai CFT2791. The set will change black level over time. The clearest example is when watching a 2.35:1 dvd in widescreen mode. In widescreen mode, the set "squeezes" to about a ratio of 1.85:1. So when watching a 2.35:1 movie, I have really dark 1.85:1 bars and then less dark bars extending from those that frame the 2.35:1 image. I calibrated the set using Video Essentials and I use mattes when I watch movies so the difference in black level of the bars does not bother me. After watching a movie with the mattes off for a while, I can actually see the bars that are part of the anamorphic image darken and approach the black level of the 1.85:1 "squeezed" bars. When this happens the overall picture becomes MUCH too dark.
I believe that the set has some kind of automatic black level adjustment that is the culprit. I tried disabling it in the service menu using advice found in this thread. First, I tried adjusting "B stretch-BTHR", "B stretch-BTLT", and "B-BAM" in the video adjust 2 menu all to zero. Second I tried adjusting "Peak Threshold" in the video adjust 3 menu to zero. After making these changes the set still does not hold black level.
If I turn the TV off and then on after the screen has darkened, black level returns to normal. Sometimes it will then stay that way untill the end of the movie and sometimes it will darken again. Also, when adjusting the brightness using the high and low APL pluge test signals from VE, I cannot get the black bar on the left to show up at all.
If anyone else knows how to fix this problem in the service menu I would be grateful. Also, if anyone has a phone number for Akai/Samsung tech support that would be a big help. Thanks.
-Jesse
I am having a serious problem with my Akai CFT2791. The set will change black level over time. The clearest example is when watching a 2.35:1 dvd in widescreen mode. In widescreen mode, the set "squeezes" to about a ratio of 1.85:1. So when watching a 2.35:1 movie, I have really dark 1.85:1 bars and then less dark bars extending from those that frame the 2.35:1 image. I calibrated the set using Video Essentials and I use mattes when I watch movies so the difference in black level of the bars does not bother me. After watching a movie with the mattes off for a while, I can actually see the bars that are part of the anamorphic image darken and approach the black level of the 1.85:1 "squeezed" bars. When this happens the overall picture becomes MUCH too dark.
I believe that the set has some kind of automatic black level adjustment that is the culprit. I tried disabling it in the service menu using advice found in this thread. First, I tried adjusting "B stretch-BTHR", "B stretch-BTLT", and "B-BAM" in the video adjust 2 menu all to zero. Second I tried adjusting "Peak Threshold" in the video adjust 3 menu to zero. After making these changes the set still does not hold black level.
If I turn the TV off and then on after the screen has darkened, black level returns to normal. Sometimes it will then stay that way untill the end of the movie and sometimes it will darken again. Also, when adjusting the brightness using the high and low APL pluge test signals from VE, I cannot get the black bar on the left to show up at all.
If anyone else knows how to fix this problem in the service menu I would be grateful. Also, if anyone has a phone number for Akai/Samsung tech support that would be a big help. Thanks.
-Jesse