DCTV and DCTG in Trinitron service menu?

[Brad251]

I have a little bit of black crush on my KV-24FV300 and using conventional methods to get rid of it has not worked. I know the FV300s have the contrast set very low by default so I increased the sub-brightness (SBRT) all way up in the service menu and that did help a lot but there is still some black crush left over. I also tried adjusting the sub-contrast (SCON) and the user menu menu brightness and contrast and that did not get rid of the remainder of the black crush.

I was going through my FV300 service menu and I noticed the options DCTV and DCTG eliminate most of the black crush when I turn those settings up but I am not sure what these settings do. DCTV stands for "DC Transfer VTH" and DCTG stands for "DC Transfer Gain". Both of these options appear to do the same thing which is make the overall image brighter and raise the black level. To get this effect with DCTV you have to increase it in the service menu, whereas with DCTG, you have to lower it to get the same effect.

Does anyone have any idea what DCTV and DCTG do and if it is safe to adjust them?

[austin532]

I have the same TV and yeah I had to increase sub Brightness almost all the way to fix the black crush. I then had to turn Picture all the way down from the normal menu as it was way to high and was interfering with the scanlines. I also had to raise Brightness all the way up from the same menu. Used the blue only mode from the service menu to adjust the color as well as tint and tried to get geometry as perfect as possible. Now it looks pretty great.

Rule #1 if you don't know what something does, don't mess with it. I wouldn't mess with the DC settings in risk of damaging something. How is the geometry on yours?

[Brad251]

The geometry isn't too bad. The only thing wrong with the geometry on my FV300 is that there is a slight horizontal trapezoid going on. The center of the screen is fine but the lower left corner angles down and the upper right corner angles up. When I play games I only notice it if a game has a life bar or something like that at the top of the screen but it doesn't bother me that much. I have the 24" FV300 which doesn't have controls in the service menu to fix a horizontal trapezoid but I think the larger FV300 models have this option.

Does your screen looked washed out with your user menu brightness turned up all the way up? Brightness and sub-brightness control the black level and on the CRTs I have owned, turning either of these up all the way causes blacks and the rest of the picture to look washed out. When I calibrate my CRTs I use Artemio's 240p suite. I start out calibrating the black level (user brightness and sub-brightness) using the Pluge pattern to get the black level to get an idea of where it should be and then I just calibrate the user contrast (called white level) by eye until just before the point where it starts to strain my eyes. With the exception of the FV310, on the flat screen CRTs I have owned, turning up the user contrast to the point where I feel the picture is adequately bright hurts my eyes. I then then have to turn the user contrast down so it is less straining on my eyes and then I turn the user brightness up to compensate. Unfortunately, this makes my picture slightly more washed out than it should be but it still looks alright.

[FinalBaton]

The geometry isn't too bad. The only thing wrong with the geometry on my FV300 is that there is a slight horizontal trapezoid going on. The center of the screen is fine but the lower left corner angles down and the upper right corner angles up. When I play games I only notice it if a game has a life bar or something like that at the top of the screen but it doesn't bother me that much. I have the 24" FV300 which doesn't have controls in the service menu to fix a horizontal trapezoid but I think the larger FV300 models have this option.

Does your screen looked washed out with your user menu brightness turned up all the way up? Brightness and sub-brightness control the black level and on the CRTs I have owned, turning either of these up all the way causes blacks and the rest of the picture to look washed out. When I calibrate my CRTs I use Artemio's 240p suite. I start out calibrating the black level (user brightness and sub-brightness) using the Pluge pattern to get the black level to get an idea of where it should be and then I just calibrate the user contrast (called white level) by eye until just before the point where it starts to strain my eyes. With the exception of the FV310, on the flat screen CRTs I have owned, turning up the user contrast to the point where I feel the picture is adequately bright hurts my eyes. I then then have to turn the user contrast down so it is less straining on my eyes and then I turn the user brightness up to compensate. Unfortunately, this makes my picture slightly more washed out than it should be but it still looks alright.

I'm like you, I set the "Brightness" (black level) wayyyy down, like 3 clicks up max, if that, and the "Picture" setting(brightness of the lighter parts of the picture) around 2 thirds ofthe way up in the regular menu.

[austin532]

The Picture setting on Sony CRT's is not true Contrast but rather has something to do with how much power the image gets. If I set it to halfway or more it starts to hum. If I set it too high the scanlines are barely noticeable. You want them to be visible on all four shades of the PLUGE and roughly the same size.

As far as Brightness no the image is not washed out with normal room lighting. If I turn out all of the lights then yeah it's a little bit brighter but I rarely play like that. I adjust Brightness until the inner bars just barely disappear in the PLUGE test.