URGENT REQUEST for help with JVC AV27S33 Tint Problem (re: calibration)

If anyone could offer me some assistance, I could really use some help doing some subtle picture calibration on my new, JVC AV27S33 television, which has a distinct "bias" toward a greenish tint. [It's clear the set isn't "defective," just in need of a fine tuning]

I know how to enter service mode, but I'd like some general suggestions regarding which particular values would likely address my set's overall tint and grey scale balance (seems that many values which should be grey, black, blue and off-white are all rendered varying hues of green). Hopefully, many of the existing, factory settings will be to my satisfaction; I mainly want to try "extracting" a significant percentage of green from the tint balance.


Also:


Which "video status" mode should I enter service mode in, "standard"?

Should my color settings be "dead center" at the time of calibration?

Would any changes need to be reflected in each video status mode: standard, dynamic, sports, etc.?

How would I go about saving any changes made in service mode, if that's not self-explanatory in the menu system.

And, again--since all the values in the JVC service mode are cryptically named/coded--what are the names/locations of some of the most relevant settings that pertain to this problem in the service mode?



Any help with this would be GREATLY appreciated! I have one final inquiry: Are JVC sets in this family--direct-view, 27 inch--capable of logging changes in the service mode which might later be used as grounds to deny me service under my warranty period?

Mostly, I've considered doing this calibration process myself because all the regional, authorized JVC service providers have refused to do in-home work for me (despite the warranty's suggesting that sets over 25 inches "may" be covered for in-home work)...and I'd rather not entrust my brand, spanking new machine to some potentially rough handling at the hands of a service tech.



Once again, I would really appreciate any help with this.


Thanks,


Jack

Jack;

I just purchased an AV36S32, and I also have the green tint problem. Have you had any success in finding a solution? Is there anything in the service menu that can help?

geo

Try posting or browsing over at www.hometheaterspot.com. They've got sections for various manufacturers.

George,


As yet, I haven't found the cause for this problem. Because my set is still under warranty, I looked into whether or not "in home" service was available in my area for JVC products. Unfortunately, it isn't--although it may be in some areas for TVs with a screen measurement of 25 inches or more (worth checking out); the JVC website will point you in the direction of regional, authorized service centers. It looks like I'm faced with having to lug the set in for a professional calibration...if I can get a service tech to perform one for me (assumedly in "service mode," doing some fine picture adjustment. On that score, by the way, I've heard that it's unwise to go into service mode yourself while your set is under warranty, since it could void your service agreement. I've dropped the idea of doing any tweaking myself...at least until I've exhausted my warranty protection). My concern is that the person who does any calibration work will suggest that there's no problem with the TV, that this is just a trait unique to JVC sets. I would find that unacceptable. Despite the fact that I'm impressed with this set in other respects, I can't say whether or not I'd seek to return it if I still had the option to do so. At this point, though, warranty protection is all I have left. I'll let you know how I make out with my efforts at getting my set adjusted/repaired/replaced...



--Jack

Jack;

Look here:

http://home.earthlink.net/%7Etlhuffman/jvc/jvc.htm

There is mention of the green tint issue. I haven't tried it yet, but intend to. Be sure you write down the out-of-box settings before you change anything so you can undo if necessary.

A related question: It seems to me that the color balance changes as the set warms up. I definitely notice the green more after about 30 minutes of operation. Have you seen that?

geo

George,


I did notice that the greenishness seemed to vary in intensity, and it's possible this correlates with the set having a chance to warm up. I'll take another look and get back to you.

Thanks for the link: one I had before but had since lost.

If you decide to proceed with calibrating your set yourself and happen to determine what service mode value corresponds with the particular tint problem we're having, I'd be interested to know what it is. It's possible our sets have the same service mode layout.

Still, I'll likely opt not to tinker and just take the unit in to see what the techs can do with it. My fear is that changes made in service mode are somehow logged, and that that could be used as grounds to invalidate my warranty should something else come up in the coming months.

Well, let me know how things work out with your set. Apart from this issue, I think the JVC AV27S33 is a great set for the money.


--Jack

Jack;

I tweaked my AV36S33 last night, and now I'm quite happy with the color. If you decide to try it yourself, let me know. I'd be glad to write up what I did. It is a bit different than the instructions on the forum for the AV36230.

Regards,

geo

George,


Glad you're happy with the color now.

I would definitely be interested in knowing what tweaking procedure you used, if you feel like detailing it in this thread. If it's not too elaborate, I might consider an attempt at doing the calibration work myself.

I'm curious whether our respective JVC sets have similar service mode layouts.

[It's probably too much to ask that JVC's service mode setting for tint balance be addressed by one quick alteration in there somewhere...]



Thanks,


--Jack

Jack;

I have not been able to find documentation about the AV36S33 nor your model. And I haven't yet purchsed the service manual. So I went into the service menu and tried to compare the settings on my TV with those described in the forum for the AV36230 and others. There are similarities, but several differences. Here are some of the highlights:

There are twelve settings categories:

1. Video/Chroma (S)
2. Deflection (D)
3. Sound (A)
4. Others (F)
5. PIP (PIP)
6. 3L-V/C (LVC)
7. Low Light
8. High Light
9. RF AFC
10. VCO
11. I2C Bus
12. System (Sys)

I don't have descriptions for most of these, but I was able to figure out the ones that affect the green tint. I've successfully adjusted it for the composite input; I haven't tried it for the others. The changes I made are only in categories 1 and 7. I haven't yet tackeled the red push issue, because the parameters that I think are for that adjustment are different in the AV36S33 than for the others on the forum. I do notice the red push some, but so far I've been able to get a lot of it corrected with the user menu (after having eliminated the green tint). I plan to work on the red push in the next day or so, but it will be guesswork as to which setting will do the job. I'll let you know what I discover.

I don't have the Avia or any other calibration standard. (I'm too frugal to buy it until I determine whether I will keep this TV or return it under the 30-day satisfaction provision.) So I hooked up my old TV in parallel with the JVC using a signal splitter. I simply compared the colors, facial tones, shadows, bright areas, saturation, etc. between the two while surfing through both antenna and satellite channels. The forum helped quite a bit in this, because I mostly knew what to analyze. For example, the color balance in the light areas versus the dark areas are different, once you realize that you should look for that. Definitely not a precise methodology, but it seemed to work. My criterion was that if I could get the color and consistency to match the old set, I'd be satisfied. I've come to the conclusion that my old set, a Sansui, has a slight green tint also. But it was subtle, and I've been happy with it for nearly twelve years. So I've achieved a slightly better quality that I had. But it's taken quite a bit of experimentation, and I'm not finished yet; I haven't twiddled at all with the composite inputs, although I think
I will know how to do it.

So here's what I did:

1. Be sure to set up a method of recording the out-of-box settings and the changes you make for each experiment. I've made 3 major passes, and I recorded the changes along the way. I also recorded the necessary settings in the user menu for each experiment. That helped me know whether I was making progress or just shoving the prolems around.
2. Use the Standard video status. (Record the user settings before you make any changes.) Set the standard status, then enter the user menu and reset all the tint, color, brightness, etc. to zero. The Sports status seems to be affected by the Standard settings, but I don't payed much attention to that. There is no "Theater" mode that I can find.
3. The first trial fixed the green tint but produced some other side effects which I subsequently adjusted. I was mostly happy after that first step, but I've made improvements beyond that. You might try the first one on your set and see whether it fixes the grenn stuff for you also.

Here's what I did:

V/C(S) S01-Bright
Factory Value: 63
My 1st change: 71
My 2nd change:71
My 3rd change:71

V/C(S) S02-Picture
Factory Value: 80
My 1st change: 62
My 2nd change:70
My 3rd change:65

V/C(S) S03-Color
Factory Value: 50
My 1st change: 50
My 2nd change:70
My 3rd change:65

V/C(S) S04-Tint
Factory Value: 50
My 1st change: 50
My 2nd change:70
My 3rd change:65

V/C(S) S11-R Cut
Factory Value: 40
My 1st change: 50
My 2nd change:45
My 3rd change:45

V/C(S) S12-G Cut
Factory Value: 45
My 1st change: 45
My 2nd change:45
My 3rd change:45

V/C(S) S13-B Cut
Factory Value: 69
My 1st change: 79
My 2nd change:71
My 3rd change:71

V/C(S) S14-R Drive
Factory Value: 77
My 1st change: 87
My 2nd change:82
My 3rd change:80

V/C(S) S15-B Drive
Factory Value:70
My 1st change:80
My 2nd change:80
My 3rd change:80

LowLight Brightness
Factory Value: 61
My 1st change: 71
My 2nd change:71
My 3rd change:71


After each one, I adjusted the user menu to get the picture as close to desirable as possible. Then I recorded those values so I could return if a subsequent test was worse.

My next step is to play with the red push. The forums say to adjust the R Y Gain, CMP R Y Gain, CD Matrix, and CMP CD Matrix. But my set has none of those. The closest thing is S21 (NTSC Mat) and S44 (V1 Gain). There are a couple other settings that look interesting, like S30 (Blue B) and S22 (Black ST). I don't intend to change those, at least not right away. Also, the 3-L V/C menu seems to mimic the V/C(S) items, but there are no descriptions in the menu. So I'm not at all sure about those. I'f I'm feeling really confident, I might test those with the composite inputs to see what happens.

Let me know what happens with yours.

Also, if any other readers of this forum can offer any information about the service menu items (description, operation, etc.), that would be greatly appreciated.

geo

George:


First, I want to thank you for your voluminous, very informative post. Without it, I wouldn't have had the courage to go back into the service mode or make the leap from taking some of the advice in that JVC calibration site intended for other JVC models...and apply some of that same theory to the adjustment to my JVC AV27S33...

I decided that I only really had one fundamental problem with the color balance of the set; too much green in both the light and dark areas of the picture. If I could remedy that--even get the balance in the ball park of where it should be--I'd be happy. My 12 service mode menu options corresponded exactly to yours, and I found everything where it should be under the first menu option (I chose only to address color issues, leaving everything else be for the time being). Here's what I did; after getting a sense of how drastic the green cast was, I ultimately ended up adding twenty points--yes, 20--to the red cuts, red drives, blue cuts and blue drives (as recommended at the JVC calibration site, I left Green alone, as a base line). I didn't even-out or "level off" any of the existing values in each of those settings categories, but simply added 20. I started with smaller leaps, actually, which didn't quite get me there... In comparison with a Panasonic I had in an opposite room where I could see it, those changes alone brought the JVC set almost exactly in line with the other set (which I've always felt had an excellent tint balance). I'm not sure about the logic of my final move, which was to add 20 points--in the direction of green--to the TINT setting (to the right) because it seemed that, after my changes, I could stand to open up just a wee bit more of the green range in the user settings. That was pretty much mission accomplished right there (as far as the composite settings were concerned). Now I'll spend a while verifying that everything seems to be in scale before I decide to do any more tweaking. In theory, by raising the r-cuts, r-drives, b-cuts and b-drives together in the exact same degree, I should only have had an effect on the overall level of green in the image. That seems to be the case.

I applied the same method to bringing the Component settings in scale, most of which were "flat" in the service mode; those settings become active when you enter service mode while monitoring a component signal. I left green alone again, and added twenty to red and blue drives and cuts. The results here are either identical to the composite results...or skew a bit toward being a bit too rosy, too blue. Here, I'm debating whether to bring everything down a notch (again, in the same degree). I also added twenty in the direction of green on the TINT scale for the sake of consistency. Fortuntately, for both viewing modes, apart from the grey scale being infected with green, most other settings seem to be in scale with what I remember as an appropriate tint balance. Not scientific, for sure, but I think I've spared myself a trip to the service tech's. The changes were simple, consistent, and designed to affect the only perceptible problem I had with the set...and it looks like I've pulled it off. If I ever do need to take this set in, I'll restore everything to the factory settings in the event they check for that sort of thing.

I may invest in a calibration disc or attempt to tackle that "red push" issue in the next few days as well. Keep me posted on your discoveries, and thanks again for all your help and input on this thread.


More soon,


Jack

Gosh, Jack. I'm certainly glad we began this discussion.

What is the JVC calibration site you mentioned? I don't think I've seen it.

Last night, I played with the MAT and GAIN I mentioned earlier. S21 and S44, as I recall. the MAT setting had more effect on red push than the GAIN. Lowering it to 000 definitely removed the red push, but a bit too much. I raised it back to 002. At that point, I was very happy with the colors. However....

Later that same evening, I played back a VHS tape I had recorded a couple of days ago from the History Channel. Yuck! Too green! I don't understand this, because all the satellite and antenna channels come through my VCR and into Video-4 input of the TV. So regardless of live versus taped shows, the TV settings are exactly the same. This was very, very disappointing to me. I don't feel this is an issue with the VCR (Panasonic PV8451), because I had both old and new TV's on at the same time. The old Sansui color was fine. I don't understand this at all. Any ideas? Have you seen anything like this?

Thanks and best regards,

geo

Jack;

Obviously, I had a brain cramp in my last response. The calibration web site was the one I had sent you earlier. Duh!



Anyway, I would be interested to know whether you have the same issue with the VCR.

Thanks

geo

George,


Sorry to hear of your being ambushed by surprise levels of green in VHS playback. I ran a few test tapes last night, and all changes made to the master, composite settings seem to apply there as well.

If your settings are still pretty much the way they were in your previous post, it's possible you didn't fully compensate for the green bias. I think I've completely eliminated the problem, but--as it currently stands--I've added a full 17 points to each of the red cuts, red drives, blue cuts and blue drives, and in cases where the JVC already recorded a value for a particular setting, I added 17 to that value; a value of 5 would become 22, for example (that way, I could accurately evaluate JVC's existing tint balance, though with significantly less green in the overall mix). Oh, I also stayed away from picture settings pertaining to brightness, contrast, etc.

One thing you could try: return everything to factory settings, then try adding roughly 20 points to each of the red and blue drives and cuts in question and see where you stand with the VHS playback issue. If the problem's solved, you may not have gone far enough with your initial adjustment to counterweight the pervailing greenish tint in all light and dark color spectrums. If you're in the ball park, you can do fine calibration from there; I've since backed off to a 17 point gain in each r and b drive and cut setting. Also, I've eliminated the comparable 17 point gain I originally had on the tint setting. I decided leaving all color settings alone--apart from the cuts and drives--would be the best way to judge whether I'd solved my problem. In theory, if things are too green I can add a few points to the r/b drives and cuts. If there's too little green, I can back off a few points.

I'm still not sure whether my fix was too much for component video; 17 points to the drives and cuts there might've been overkill. I may back them off to 15 and see how that looks.

Good luck with your set, and I'll keep you posted on any discoveries I make. Before I look into "red push"--which I'm probably not particularly sensitive too after seven months with this TV's being way too green!--I'm going to be sure the other settings are pretty much dead-on first.




By the way, any guess on where I might find a Vertical Size setting in the service menu? I've been curious whether it would be possible to perform the "anamorphic squeeze" trick for dvd playback with this particular model. With certain older JVC sets, it was rumored that one setting change was all it took for a perfect squeeze down.




Keep me posted,


Jack

Jack;

I definitely saw the vertical size. I'm not at my set right now, but I think it was in menu #2, the Deflection settings.

Thanks for you response. Actually, last night I did try what you suggested. Adding a certain number of points to the cuts and drives didn't fully fix it; the Picture setting was important also. I think that's because Picture affects contrast, and in areas where there is quite a bit of color contrast, the red/green imbalance gets emphasized.

One question. Rather than adding a specific number of points to the cuts/drives, should we instead add a certain percentage of the original? Otherwise, the balance is changed. In my set, the factory settings had the blue quite a bit higher than the red. It seems if the blue starts at 50% higher than red, it might make sense to add 50% more points to blue as a starting point. What do you think? Actually, the bottom line is whether you achieve the color you want. If so, nothing else matters.

I'll try a couple more things, then decide whether to return the unit. It will be a couple of days before I can do that. I'll give you an update then.

Regards,

geo

George, I'm not at all sure about the percentage increase issue; you may have a point. My goal was to basically--in an accross the board fashion--shift the entire grey scale color palette away from green and more toward blue and red, hopefully achieving a more neutral grey scale that's uncontaminated with green; in other words, I wanted to redefine "color neutral" for the set (it used to be that when I bottomed out the color in the user settings, everything was still tinged with green). My thinking was that the values that were already present--including the increased output of blue you mentioned--might already represent a proper relationship of blue/red/and green in the grey scale if it weren't a matter of the overall grey scale balance being shited too far toward green. So, if I could push the entire grey scale spectrum toward blue/red by adding some fifteen points to each of the red and blue drives and cuts am I preserving that original calibration, albeit in less green neighborhood, or am I introducing more balance problems? Sorry if I've been repeating myself, but I guess it boils down to the question of what exactly the recipe for a universal, full spectrum shift toward green that doesn't muck with the other color calibration/relationships is...

As an example of what my thinking was: If instead of zero as representing neutral in the grey scale value in the JVC service mode settings (which we know to be far too green), I redefined zero with a value of 17 points in composite mode and 10 points in component mode. On top of that, the set's previous settings are still present, making the full equation zero--redefined by myself as "17"--plus whatever previously existed. So, in my possibly bogus theory, we have the same color relationships in the grey scale, albeit with much less green. The other factory color settings stand. At that other guy's JVC website, he sort of described grey scale calibration as changing the color of the light bulb in the room you're viewing a painting in; we were stuck with a green bulb. By changing my bulb toward a neutral white, the factory settings for color, tint, picture and brightness, etc., might well be fine now that I can view them in a less green biased environment. But again, I admit that I was winging it with my strategy. Also, I should mention that in all cases, I've never touched the green grey scale setting.

If I did the wrong thing, somehow I lucked out and it worked like a charm. I've discovered that my component mode doesn't need as much of a kick in the blue and red pants; I've since dropped that back down to a 10 increment increase on the red/blue cuts and drives. My composite mode's still been upped by 17 points in that department, but in both modes, I've reset my TINT control to factory levels. My reasoning for that was that that setting should still be fine with a properly--less green--adjusted grey scale.


In other news, I experimented with the anamorphic squeeze trick, which works fine with the AV27S33. You were correct that the setting was under the second menu. It's easy enough to do that I expect I'll try that for my next "enhanced for 16 x 9 widescreen" dvd, though I'm going to be careful with contrast...as some have cautioned about phosphor burn-in when using the sete in this way for prolonged periods. I don't have time for the details at this point, but an additional step is required to cover a few junk lines of resolution that come into view with the V-size scrunched down (there's a drop down black matte that covers them, but it also unfortunately crops the very top of 1.85:1 transfers). Still, pretty spectacular, and easy to perform.



As always, keep me posted on any points/tips/discoveries.

Let me know if you want to try the anamorphic squeeze and I'll go into greater detail next time.




--Jack

George,


Here's the procedure for anamorphic squeeze; hope it applies to your set (a feature found mostly on much more costly sets). Let me know if it works...


Enter service mode, then under option two, decrease D07 V Size to about 16 or 17 (you could mark the proper image height on the screen--with post-it notes--of the widescreen image during dvd playback in 4:3 mode for a more accurate approach).

Then, to remove garbage lines of resolution that come into view at the top of the image, increase the value of D17 WVMT to 1, 2 or 3, depending on how low you want the drop-down black matte to go.

D18 WVMT BTM extends a black matte from the bottom as well, if you need it.


Exit out, and that should do it; just tell your dvd player you have a 16 x 9 tv. Again, though, I've been warned about having the contrast too high in this mode, as it's pretty punishing on the screen phosphor, and I guess it's also good to do a fair share of full screen viewing on the set to balance out the wear a little.





Well, I'm now completely happy with my set.

At this point, I'm down to an 8 point gain on red and blue cuts and drives in component mode, and 17 still seems appropriate for composite viewing (not at all sure why). In terms of adjustment, though, my TINT control is almost dead center for optimal color balance in each mode.

Any clue about correcting screen geometry problems?

Seems like horizontal size is locked down in service mode, fixed at "32" in the JVC AV27S33. I was also looking for a means of slightly rotating the image, clock-wise, but I'm not sure that's possible. I expect that this set will always have minor distortions since the screen is very convex. But then I've heard flat screens are distorting as well.




Finally, as for your problem, was it just that one tape that was still too green for you? Did you opt to keep the set or junk it?



Thanks again for your input in this thread; you were instrumental in helping me solve all my gripes.



--Jack

Gosh, I appreciate your description of the squeeze. I was going to experiment with it.

I've not had adequate time to make a final decision about keep / return the set. But I did what you suggested: return everything to out-of-box and only twiddle with the cuts and drives. I decided to use a percentagea approach, because the blue cut was much higher than the red cut to start. I added 25% to each R-B cut and drive. That got it pretty close. I then reduced it to 20%, which is an increase of 8 points for the red cut. I'm rather happy with it right now. There seems to be a bit of red tint, but it's actually more desirable than my old Sansui; as I mentioned, through this experiment, I've decided that my old set was too green.

Last night, I put the VHS tape back in, and the green is essentially gone. Puzzling, but obviously something I had set a few days ago had an impact on the picture quality from the recorded tape. One thing I'm thinking is that the tape picture had some minor ghosting even though it was from satellite. So maybe the ghosting caused the colors to split out somehow like a prism. Then, having the contrast and detail set high might have caused the green tint in areas where RGB should have been focused and creating the proper color. Anyway, it's OK now. I don't even notice the red push. I haven't played with any of the other three inputs, but I assume those adjustments will be similar to the video-4, which is the coax composite input that I've been working on. I plan to do more experimentation this weekend and make the keep / return decision. I'll let you know. Right now, I'm thinking KEEP.

I think I saw screen geometry settings in the Deflection menu, but I'm not at my set. You could search this forum also. I'm sure I've seen threads about geometry and how to fix them. The specific settings will be different for our models, but we could probably figure it out like we have the others so far. I'll look also when I get a few minutes.

By the way, I searched Consumer Reports for brand quality and reliability. JVC was not the best, but was in the best 20% for reliability. I was surprised to find Sanyo as the most-reliable, including Toshiba and Sony, in the category where Sanyo was evaluated. The Sanyo picture quality didn't get good reviews though. I was doing this research to determine whether there is any brand and model that will meet my criteria (fit into my entertainment unit), and WalMart has a 35-inch Sanyo that would work. I don't intend to do that if this JVC works out.

Thanks again for the chat. This is really useful and educational.

Regards,

geo

Hi, Jack.

I fiddled with my colors a bit tonight, and I think I've reached a point where I'm happy. Still no change to the red push, but it doesn't seem necessary. I lowered the blue cuts to be more comparable to the red and green. But the blue is still higher. My next step is to adjust the color, tint, brightness so the user menu has a reasonable range. But for now, with the video-4 input, I'm happy.

The Deflection menu has several items related to screen geometry. I haven't done anything with any of them. Here are a few of interest:

D09: V Center
D13: V Linearity
D15: Horizontal size (I did play with this one and confirmed it affects the horizontal. My initial setting was 24.)
D23: Trapezoid

I would imagine they work much like a computer monitor. There are other variables which sound interesting, but don't look obvious. Do you have a guess about any of these?

D17: WVMT Top
D18: WVMT Btm
D19: EWCR Top
D21: EWCR Btm
D23: EW Para (Parabolic?)

Finally, in the system menu, there are settings that seem reasonable, like hyper sound on/off. But here are a couple that look relevant to what you and I have been doing:

Sys06: Purity
Sys09: Clr Temp

Maybe I sould stop being so cheap and purchase a service manual. But if I did that, where would we find the challenge of discovery? :-)

geo

George,


Thanks for the tips; I'll check some of those settings out.

I do know that the WVMT Top and WVMT BTM settings control a black matte setting that either descends from the top or rises from the bottom to cover lines of resolution and such that come into view when doing that anamorphic squeeze down. Not sure if that's their intended use, but they seem to be useful in that regard.



Also, I'm back up to a 20 point gain in both composite and component; saw just a few instances of darker parts of the image contaminated with inappropriate green while watching a dvd again...so it turns out the two modes seem best when they're neck and neck in the red and blue cuts and drives department.

Again, as for settings in composite, everything that was initially higher in those areas still is, since I dded 20 points equally, to everything.


Weirdly enough, horizontal size seems frozen at 32 of the AV-27S33. Weird.



I'll tinker with some of the other settings you mentioned, see what happens...




--Jack

Just to clarify, when I wrote that horizontal size was "locked down," I only meant that changing that value had no effect. I can certainly change the number value, but the screen just flickers. Weirdness. Well, the geometry on my set seems pretty good for such a convex screen, and I don't think I would bother correcting what they call "overscan," so I doubt I'll need it. But I'm left with the question of whether this is normal or not.


I might have already mentioned this, but you'll probably be thrown by the fact that all the cuts and drives settings in component mode are initially flat (at zero). I initially experimented with simply adding twenty to all red and blue cuts and drives--leaving green at zero--and also replicating the values in composite mode, which is obviously not the thing to do based on the results I got.

In the end, adding a uniform twenty to everything but green seems to have created an almost identical color balance to what I have in composite mode (where I also added twenty to the existing values of all cuts and drives but green).

My final composite settings:


S11 R Cutoff 88
S12 G Cutoff 40 (unchanged)
S13 B Cutoff 86
S14 R Drive 95
S15 B Drive 84

again, that's all original values plus twenty, except for the G Cutoff...

Final Component:

S16 R Cut 20
S17 G Cut 00 (unchanged)
S18 B Cut 20
S19 R Drv 20
S20 B Drv 20





--Jack

Thanks, again, Jack.

I've spent lots of time over the past several days trying to get the color right. Several times I've got it to the point where I'm quite happy, then later I find myself tweaking again. So I decided to set everything and just leave it alone but watch to see whether anything changes. What I've discovered is, as I mentioned to you several days ago, the color balance is not constant. It changes over a period of perhaps 1/2 hour as the set warms up and also from channel to channel, especially from satellite to antenna. So having verified that, I'm again not very satisfied. Have you noticed this sort of inconsistency at all?

I decided that the red push does need attention. Without modifying this setting, most of the picture looks dull and washed out if I set the facial color correctly.

I have eleven more days to decide whether to keep the set or return it for refund. I'll decide by this Friday so I can move onto other things.

Regards,

geo

George:


First, just a quick favor: I wonder if you could tell me what your factory setting value for "S21 NTSC MAT" is--under menu option 1 in service mode--while monitoring V2 as an input source (or whatever input source corresponds on your set with component input for dvd, etc). Stupidly, I never recorded the factory pre-set under that mode and accidentally changed it. No big performance issue there, just didn't want to lose track of factory settings in the event that I have to re-set them all before taking the unit in for any possible service during warranty period. Of course, yours may be different; I'm pretty sure mine was initially on "002," and I guess I'm just looking to validate my hunch. Thanks a million.


As for color hue incosistency, I do notice a broad range of discrepancy from source to source under composite (antenna and satellite), and I find myself compelled to tweak virtually each and every channel in the user settings if I stay on a certain program for more than a minute or so. But then that's my usual drill on any television, since--even from commercial to commercial, program to program--the color spectrum changes drastically along with the quality of the original video source, etc.

Your best bet for determining if you still have a probelm there would be to compare the JVC to your old standby set again to see how it handles some of the same images. Because there's a lot of stuff out there that simply looks crappy and poorly balanced on the best calibrated sets.

In terms of a gradual shift in color balance as the set warms up, I have read references to waiting about a half hour before doing any fine adjustment because of this phenomenon, but if you're seeing a striking difference, I just don't know. Could be a dramatic shift is a sign of a problem, but I imagine subtle "warm-up" differences are just a reality of the hardware involved. That probably doesn't help you much.

In terms of that washed-out look you're associating with red push, it could also be a sign of pushing the red and blue cuts and drives just a little too far when compensating for the greenish tint. That's the real trick of this game; eliminating inappropriate, problem green while not drowning everything in a blue/red haze. It took me a few tries to get it in the ball-park, and the rest I can handle in the user settings... If you haven't already tried it, experiment with adding a fixed number--not a percentage--on top of each of the red and blue cuts and drives settings and then watch a few things whose color balance you know really well; subtly back off on or ratchet up the drives and cuts a few points until your TINT range seems faithful. Then see if it stacks up against you other set on a wide variety of channels, video sources. I'm sure you've been there, done that, and I wouldn't blame you for junking the JVC on the grounds that life's just too short... I'd go with my gut if I were you.

Boy, this has been quite the journey, hasn't it?



As for things on my end, last night I took a look at "The Ring" on dvd again, which was probably the most heinously, wronfully green thing I ever watched on the AV-27S33 before calibrating the grey scale, and was pleased to see that the tv was now properly decoding the predominantly blue/grey, and deep blue/green color scheme as blue/grey and not green/green, green and more green. It was a nice way to celebrate my washing my hands of this business!


Well, I hope your decision making process isn't too arduous or unpleasant.


Keep me posted...


--Jack

Jack;

I'm very familiar with S21, because that and S44 are what I've been using to correct the red push. S21 default was 003, which is also the maximum setting. I didn't see any effect of reducing that to 002 or 001. But in going from 001 to 000, the red push was significantly changed.

Yes, I have been comparing the JVC to my old set when I notice the variation of colors. For example, when I first turn on the set, it's too red as compared to my old set. Then gradually it changes to be just fine or slightly green. I've tried to watch/confirm that my old set isnt' really the one changing, and I think I have verified that. Even looking just at the JVC I notice too much red during the first 30 minutes or so, then OK or slightly green. Same for comercial variations. The old set handles the variations much better.

Yes, I've tried the fixed 20 points or so addition. Perhaps I wan't careful enough to change one thing at a time and really notice whether it fixed the problem or just added another issue. I think I'll do that one more time and be careful to note the effect.

Yes, I think this has been an interesting journey. I've learned quite a bit, although not sure how I'll use that knowledge in the future. :-|

Thanks again for your inputs.

geo

Thanks, Geo. Just to verify, that default setting for S21 was for component--V2--and NOT composite (V1)?

I did notice an improvement in overall redishness when taking that value a few notches, so now that I've established the factory pre-set, I'll experiment with leaving it down for a while.

S44 I haven't tinkered with, so I'll check the effect on that as well.




As for the 16:9 feature possibly being built-in to some JVC sets...while it's only accessible through manual tinkering in most--if not all of JVC's domesitcally sold sets--I noticed an interesting toggle switch value under the System menu in service mode. Don't remember the name, but it was called "16:9 mode," with either a zero or one value. It'd be interesting to know whether--with a "1" plugged in there--if there'd be any way to get the set to kick into that mode automatically with the right hardware; a remote with a 16:9 button, say. Guess I'm not likely to ever know, since I'm sure these US sets just aren't hard-wired for it. Good thing I can do it in service mode...


--Jack

George,


One quick addition...as I'm beginning to border on obsessing over this thing.


I did notice EXACTLY what you're referring to in terms of a reddish, almost purple pre warm-up sepiatone that's present for a few minutes before the color and tint balance normalizes, so it's very likely a quirk of this particular make of set. Couldn't have lasted more than five to ten minutes on my unit.

If you're sure you can't live with that, your decision making process may have just gotten easier.


--Jack

Jack;

Sorry, I misled you. The S21 default value of 003 which I gave you was for the composite input, not the component input. I checked the default for the component, and it's 002 as you also found.

Yes, I noticed the 16:9 setting also. Are you thinking that it would auto-set the anamorphic squeeze mode? No harm in playing with it to see what happens, right? ;-) I also noticed a PIP setting that could be set to 1. But even if it can be enabled, a remote would be required to select the channel. I wish I knew someone who owned an AV36S36 so I could borrow their remote and play with it. But, of course, if I don't keep the set, it's academic anyway.

Yes, I suppose we are both obsessing over this. Seems we are geeks at heart and can't give up without conquering this thing. Concerning the initial red/purple warm-up, one idea would be to use the Standard-Dynamic-Sports video status menus to correct for it. That is, have the Standard settings be what you want for steady state, and have the Dynamic settings correct for the warm-up color. Start with Dynamic, then just switch to Standard after ten or fifteen minutes. It's a kludge and only a partial fix, because the cuts/drives would probably need to be adjusted to really clean it up. But the video status is probably adequate as a compromise.

Still undecided about keeping my unit. Ten days to go. I'll let you know.

Regards,

geo

Jack;

Last night, I viewed a VHS tape which I had recorded earlier this week. I had both old and new TV going through the entire program. Prior to watching the recorded program, I surfed some of the satellite and live antenna channels. The colors on the live programs was rather OK after the initial warm up period. Then I began the taped program. For that program, the JVC color was very red, while being essentially OK on my old set. About 1-1/2 hour into the 2-hour program, the color on the JVC suddenly became much better. Still a bit too red, but not objectionable. After the program ended, I rewound to the early portion of the tape where I had seen the excessive red. It was essentially OK, whereas it had been much too red an hour before. So I feel I've confirmed that the JVC has non-constant color balance from time to time. I feel this is unacceptable, because no matter how much tweaking I do, it will never be correct. The set is going back this Saturday.

Before returning it, I plan to play around with some of the other service menu items, like the 16:9 and PIP. I'll let you know if I find anything interesting.

My next step is to try another 36-inch brand or model. I won't do that until late May, due to vacation plans. Keep in touch, and let me know if you discover any more useful or interesting information.

Best wishes,

geo

Geo,

Thanks for looking into that S21 setting for me; I've got it straight now.

All we need to see if those internal settings "enable" automatic features like 16X19 is some kind of interface, a button or something. It's a good bet the circuitry just ain't there to make some of these things happen. But it's great that it's very easy to do a manual anamorphic squeeze; I've watched a couple films this way, and it makes a big difference. I lose all sense of lines of resolution. The image is very detailed, razor sharp; film-like.

Based on what you're seeing with significant color changes over such long periods, I can't fault you for deciding to return your set. Fortunately, whatever change I do notice comes in the first few minutes of warm-up, and from then on things seem very stable.

I've gone back and forth on this, but it's now apparent that the component mode will require less of a boost to eliminate the greenish tint. A full twenty point increase on the red and blue cuts and drives--which is perfect for composite mode--is just overkill for dvds. So I'm back down to 15...and as I view more things I'll drive that up or down until it's as close to perfect as I can get it. "S21 NTSC MAT" may ultimately play a role in all this too, since--when zeroed out--it does make a hell of an impact on how much of a kick the reds get. That one setting has probably solved "red push" for some people.



Well, may your next set serve you better. Let me know what you go with, how it performs, etc.


On a side note, Consumer Reports recently published their "Biggest TV Issue Ever" which might come in handy--the March 2003--issue, and they do a breakdown of some conventional TVs in the 27, 32 and 36 inch measurement. I was pleased to see they rated the JVC AV27D303 very well--their #5 rated model--since that set is almost identical to mine in the picture department; it just has marginally better speakers for 30 bucks more than what I paid for the AV27S33. But since I intended to bypass the built-in speakers anyway, going with the cheaper model was a no-brainer.




--Jack

Jack;

I'd appreciate any updates you have, even though I'm returning my set. One of the alternatives I'm considering is a different JVC model, specifically the AV36320. So probably most of what you and I have discovered will apply to that model.

Thanks for the tip about Consumer Reports. I'll definitely review it.

geo

geo:


Made a few discoveries in adjusting my ol' JVC-AV27S33 (yep, still tweaking!).

I increased the blues while taking several points off the Reds. Seems to have made all the difference, and I can stop kidding myself about having gotten it right the first time. I've moved far enough away from green, while dealing with the side effect of things getting a little red-biased. I'm dead-on with my reference Panasonic, but for opting for a tinge less green overall.

I'm done now... And hey, the process only took a few years off my life.

For kicks, when I'd finished, I reset everything to factory defaults and was aghast all over again at JVC's allowing product to leave the plant with the grey scale so throughly off-the-mark.


my first stab:

S11 R Cutoff 88
S12 G Cutoff 40 (unchanged)
S13 B Cutoff 86
S14 R Drive 95
S15 B Drive 84


the revised and final attempt:


S11 R Cutoff 79
S12 G Cutoff 40 (unchanged)
S13 B Cutoff 88
S14 R Drive 80
S15 B Drive 88


original factory settings:



S11 R Cutoff 68
S12 G Cutoff 40
S13 B Cutoff 66
S14 R Drive 75
S15 B Drive 64






AND:


I've discovered that my component--V2 Mode--settings need no attention at all. In theory--if I understand this correctly--the signal from my dvd player is delivered to the television with independent Red/Blue/Green signal information, and that with my TINT control left at dead center...I'm pretty much getting a faithful rendering of the source signal. Compared againt my computer's default setting dvd output, this seems to be true.

Initially, I had kept my TINT settings used in composite mode for dvd viewing in V2 (component input), with disastrous results...because pre-calibrating, I'd often had the TINT bar very far left, which has the ironic effect of introducing green into grey/blue color spectrums, which created the impression in certain films with a heavy grey/blue color scheme--"The Ring" for example--of the greenish grey scale problem also being present in the component mode. Not at all true.

Why would green ever be introduced by going left on the TINT scale? Not sure, but I've verified that this also happens on my Panasonic TV and computer in certain color spectrums. Flesh tones will get redder, but other hues often go in an unanticipated direction (as toward green, say)...and it all probably has to do with color relationships I don't fully understand yet.


So, in component mode, less tinkering--in fact, none at all--seems to be more. This is supported by the fact that all the the grey scale adjustments in service mode are zeroed out in V2, suggesting the TV "defaults" to the parent signal coming in from the dvd player over those independent red, blue and green cable inputs. With composite mode (V1), I think all the color information comes in over one signal...and so the TV needs be instructed--via each of the drives and cuts--what emphasis to give each color element.

Just a theory, based on only a little knowledge, and I may or may not be off base.



As far as my component service mode settings (V2) are concerned, though, factory defaults seem quite fine--terrific, in fact--with the past few films I've played, with the TINT user settings at dead center... If I find this not to hold true, I'll let you know.


--Jack