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Stereomaniac
09-22-2005, 03:08 PM
I have a Denon DVD-910 using component vidoe into a Panasonic Tau.

My problem is when I play DVDs the picture is very dark. I like to watch horror/sci-fi movies which doesn't help. I seem to be losing detail in the background. I can play with the Brightness and /or Picture settings with moderate success.

I turn the Black Level to on on the Denon DVD-910 and the details come out of the background and I can turn down the Brightness/Picture considerably, but the picture has a very subtile bright-haze to it. I also get a sort of low level brightness flux in the picture in dark scenes. I guess that is an "disagreement" between the processing on the Denon and the processing on the Panasonic?

Is this an issue with either of these pieces? With the Black Level off, am I trying to brighten up and pull out details that are not really meant to be pulled out? What does Black Level "really" do anyway?

Also, any opinions on Velocity Modulation? I have heard lots of bad things about how it can distort the picture...?

edtyct
09-22-2005, 04:38 PM
The black level control in the Denon menu, when set to on, actually truncates low-level black information. Disable it to retain every bit of dark detail that your display will allow you to see. Scan velocity modulation is one of those features that manufacturers add to consumer displays basically because they can. What it does on your CRT is speed up the electron gun for dark imaging and slow it down for bright imaging with the intent of enhancing both. But on complex material that includes dark and light elements at the same time, it can get its signals crossed and crush detail. It also thickens edges, thereby giving pictures an artificial look; dividing lines on your TV screen definitely aren't what the doctor ordered. Disable it.

You can't pull detail out of a DVD or a display that you aren't meant to see, but you can hide detail that you should be able to see by mishandling your settings. Some of what you've noticed (haze, brightness flux) may be due to the interaction of the Denon's black level control and SVM, as well as the set's inherent capacity to retain black level when something bright is on screen at the same time. The Denon is tilted toward brightness, anyway; the last thing that it, or the Panasonic, needs is any encouragement in that direction. The brightness and picture controls on the Panasonic are interactive; they can subtly improve or impair each other's performance. It's very hard for the naked eye to set these controls correctly. I suggest that you get a test DVD like Digital Video Essentials or AVIA to set brightness and picture, as well as adjust for optimal use of the sharpness and color controls, which can also wreak havoc.

Ed

Stereomaniac
09-22-2005, 05:39 PM
Thanks.

What you said about SVM is exactly what I was noticing on the screen. I seemed apparent even on broadcast picutres. I will definately leave it off. It is one of those flashy bells and whistles that looks good in the store and gives apparent "added value".

I do like the Black Level off most or the time. I don't get the picture/brightness flux, but I can see more very dark background detail like the outline of a door or something on a table at night with the black level on. I some cases with the Black Level off I can't even see the thing on the table with the brightness or picture cranked all the way up on the Tau. That was why I asked if I was over-driving the the image to try to "see" things that I really wasn't meant to "see" clearly. Is the Sound and Vision DVD easy to use? I have heard some discs want you to go into service menus.

edtyct
09-22-2005, 07:32 PM
I haven't seen the Sound and Vision DVD, but from what I've heard, it may be the easiest to use. The worst thing about DVE, which I like a lot, is navigating it. The basic test screens are informative and fairly straightforward when you reach them, and the montage of scenes is so well shot and presented that it pops out of the screen when you've calibrated correctly. DVE doesn't explain all of the test screens that it makes available, but the bread and butter ones are completely accessible and understandable.

I see what you mean about overdriving. Even though you're tempted to boost brightness/picture to squeeze out detail, however, you may be doing more harm than good. Sometimes a TV just can't deliver all of the possible detail at its best setting from the user controls, but a little black crush is prefererable to the damage that too much brightness can cause--both aesthetically and physically. The jury's out, however, until you try establishing the levels with a good setup disk. You may be surprised at what you can accomplish with a little method to your madness. Every such disk stops short at the service menu, often recommending professional calibration for certain conditions that the user controls can't always reach (like accurate color temperature and color matrix). Some of the programming within the service menu for color and grey scale requires very sophisticated equipment and technical know-how. Other things would certainly be within the range of the enthusiast (like taming a tendency toward red, for example, which many TVs exhibit). But many people find that they can be satisfied with what the disks alone can offer, especially given the pitfalls of a misstep in the service menu labyrinth or the cost of professional calibration. Try a disk; it won't be expensive.

Ed