AVS › AVS Forum › Display Devices › Display Calibration › Bizarre Image Problems
New Posts  All Forums:Forum Nav:

Bizarre Image Problems  

post #1 of 4
10/7/05 at 2:13pm
Thread Starter 
LONG post but please read...I'm desperate!!!! LOL

Am I asking for too much out of a TV that cost me $650 Canadian, or should this damn thing be sent in for repair!

I want to hear all the suggestions I can, no matter how crazy they may seem! :rolleyes:

Okay, I bought a JVC television 4 months ago. The model is AV-32F476.
The picture quality is great, couldn't be happier...but there is one thing that is really bugging me. It seems to "bloom" pretty badly, but only sometimes. I can't figure out what makes it so bad one day, but not that bad the next.

And I'm not entirely sure it IS blooming...maybe it's something else. It's really hard to describe but the image changes size/shape sometimes, mostly when it goes from bright to dark or visa versa. For example, if I'm watching an NHL game on TV and just fix my eyes on the superimposed score board, I can see it changing size constantly as the camera moves up and down the ice. I think because of the white ice.

But it's weird, it looks like any colors on the screen try to 'run away' from any white on the screen. I have a service call in but they want to come and pick my TV up next week. I'm not sure the problem is THAT bad that they need to take the TV away for a week.Especially since they may not even notice an issue when they have the TV. However, this is the only place in town that actually gave me a straight answer. Every other place tried to blame the sattelite provider....well DVD's do it too...though not nearly as bad. But again, in Widescreen most of the screen is black.

Does anyone else own this model or even a JVC with similar problems??

TO NOTE: The image problems completely go away when I turn the TV to "theatre" mode....however, the picture is total crap...it's WAY to dark.
I know the contrast is always set WAY to high and that can cause it, but I calibrated using the Digital Video Essentials disc.

Any other ideas??
Service menu tweaks?

Oh, and I emailed JVC a month ago. No response. That's quality. I knew I should have bought the Toshiba. My girlfriend thought the JVC looked "prettier". DOH! :(

AVS Top Picks

post #2 of 4
10/7/05 at 2:51pm
Greetings

You need to recalibrate with the test disc ... but this time knowing that it does not teach you how to set contrast. The contrast pattern ... pluge bars and needle pulse are only there for you to determine where not to set contrast to ...

Proper contrast for a set like yours is set with a light meter on a 100% white window box pattern. Since you likely don't have such a thing ... you need to follow a good rule of thumb when eyeballing contrast.

Use the 100% windowbox ... or pluge boxes ... and look at the white box. (In a light controlled room) Ask yourself if the box looks too bright and is causing eye fatigue? Eye fatigue = bad = contrast too high.

This will help you to get a better calibrated image from the test disc.

Do contrast first ... then do the brightness pattern.

Regards
post #3 of 4
10/7/05 at 3:01pm
Typically blooming is the result of an inadequate power supply (a large white area takes a lot of power to display).

DVE has test patterns for this. The first is under TITLE 7, CHAPTER 8. The second is under TITLE 12, CHAPTERS 2 through 4, and 9 through 13. Title 12, Chapter 4 is the classic power supply test - if the vertical bar (Needle Pulse) bends as it transitions from the white background to the black background, then the power supply is weak (not enough storage capacitance and/or power capability).

The only way to get rid of this (or reduce its effect) is to drop the white level (Contrast) as you've noticed (by going to the Theater mode). You need to plug in DVE and recalibrate (using either TITLE 7 (basic) or the screens in TITLE 12 for setting Contrast) for both your normal and your Theater modes. You crank up (or down) the white level (Contrast) until you just start to get the "blooming". You will have to adjust Brightness (Black Level) again (go back and forth between the two to get the maximum gray scale range).

NOTE: Almost all TV sets do this (they're saving money). I see some bending of the "Needle Test" bar even on my 27" Sony XBR set, but it's not so bad that it affects the picture (a hockey game is probably the absolute worst test, because of the white ice - that's why one of the Canadian teams was toying with coloring the ice blue).

Your only solution may be to get rid of the JVC set :eek: . BTW, most of the lower cost TV sets have this problem in spades :mad: , even premium brands.
post #4 of 4
10/7/05 at 3:15pm
Thread Starter 
I adjusted the contrast/brightness settings on my TV and it appears to have solved the problem.

While the contrast and brightness were set properly in respect to one another, I didn't realize they were both out of whack (too high). I went back to the DVE disc and started by turning the contrast WAAAY down. Then on the test pluge I did as suggested in an earlier post. I waited until the brightest white box looked bright, but not too bright...this was surprisingly easy to see.

Now the picture doesn't change size at all. It looks a LITTLE dull to my eye but
a) that's probably because it was just "lit" for the past 4 months
b) if it fixes the image problems it's a small price to pay.

Thanks for the help guys...I'm cancelling that service appointment now!
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Display Calibration
This thread is locked  

AVS Top Picks

AVS › AVS Forum › Display Devices › Display Calibration › Bizarre Image Problems