XYMer's Home away from Home

Got lasik done more than 10 years ago.
Couldn't live without it.

Very easy and painless procedure.
I'd go through it again without a second thought.

The only disconcerting moment is smelling the burning of your eyeballs...
And maybe that drive-thru sense, where you only got to know the doctor for about two minutes.

And the halos around lights for a year at night.
Driving was scary for a bit.
Supposedly results are much better ~ and now, my vision is pretty much perfect.
Can't complain.

Yeah, I've heard the laser surgery is a lot better now. Supposedly with the newest procedures the slices are smaller and they can even tweak things later.

It sounds sort of appealing, but I don't need my eyes tweaked yet. Maybe once they've stopped tweaking themselves I'll consider it. Plus, for geology I can see incredibly tiny details in rocks without a hand lens.

- Anonymous

For as long as I have known my grandmother (since 1970), she had worn eyeglasses… until late last year when she had the Lasik™©® procedure done. It was strange seeing her the first few months, since I had only ever seen her wearing glasses… well, except for the time in 1979 when I watched her waterski behind my grandfather’s boat (Volvo-powered!!!) back in 1979. She says she has no regrets.

-he who stacks pork

If you enjoy finding patterns and images that interact oddly with LCDs, look no further than this page:
http://www.techmind.org/lcd/

There are many patterns that help you figure out how the underlying signaling is working.

I found the page while I was looking for details on the subpixel geometry in my Vizio, and the many other patterns that I suppose may be used in modern LCDs. My display doesn't use the normal parallel bands of subpixel elements; the bands are kinked slightly in the center, and perhaps a very tiny gap running horizontally across the kink (but it's hard to tell without better magnification).

Unfortunately I can't offer a picture of the subpixel geometry because I don't have any optics that will clearly resolve it for my camera.

- Anonymous

My initial enthusiasm for the Vizio VL320M has been tempered a little bit, now having lived with it for few months. I have a few quibbles, and what I suspect is a significant design flaw.

The two quibbles are that it takes a few minutes to warm up to full brightness, that it displays a blazing blue image with the text "no signal" superimposed whenever it doesn't have a signal, such as when the computer is disconnected or asleep, and that it takes an annoyingly long time to display anything once it starts receiving a signal. It would be very much nicer if it would simply go black after a few seconds when it's not receiving any input. As for the warmup period, it's not really very annoying and kind of expected from a conventional backlight. If I had paid a lot more for LED backlighting it wouldn't happen, but that would have been significantly more expensive; bear in mind we're still talking about a 32" monitor for $399.

The suspected design flaw is much more serious. Basically, it seems that horizontal red color data are lower resolution than the display panel. There's a very noticeable pixel-by-pixel smearing of red, and the degree of smearing increases and decreases every other vertical line. It's easiest to illustrate with some thumbnails (click for higher resolution):

This is how things should look: sharp. Note the colors are dominated by channels other than red:



The verticals in the first letters are lined up on a "sharp" line. Notice the vertical lines in the letters "l" and "n" at the start of the words:


Now lined up on a "blurry" line, by shifting one pixel to the left. Notice how much worse certain letters look than in the previous example. Others look better, but that's little consolation:


This is most noticeable when I'm working with colored text in the terminal, but I can see other places as well, always in areas with fine detail and a saturated red channel. It's like the red chroma data are lower resolution than everything else. It's reminiscent of, but distinctly different from, the old DVD chroma bug.

All the image processing features of the display are turned off and toggling them through their different settings makes no difference.

I don't know exactly how the video signal is encoded, what kind of color model is used, or anything else. If you have any insights, please post!

- Anonymous

You failed to mention a few things, namely how your computer is hooked up to the TV (HDMI-HDMI, HDMI-DVI, DVI-DVI, DVI-VGA, VGA-VGA), whether or not you have overscan enabled/disabled, what your TV's native resolution is vs. your computer's output resolution, and very importantly, your video settings.

If it's anything like Samsung TVs, you're going to have to use a very specific port to allow true passthrough. What you're seeing is almost assurely what happens when an image is downsized, then re-scaled up to the TV's native resolution via the TV's built in scaler.

Edit: It may also be that your GPU's scaler is double-dipping with the TV's scaler. The HD3870 in my Mac Pro will do that with my Westinghouse L2410NM 24" LCD unless I disable the GPU scaler (no, I cannot tell you how I do that). This is also one of the reasons that people hate font smoothing so damned much - often times the scaler interferes with the smoother, creating a VERY headache inducing image.

Fair enough. I'm connecting a MacBook Pro through DVI to an HDMI port on the TV at 1920x1080 (progressive) @ 60Hz with overscan enabled. The TV's native resolution is 1920x1080 (progressive scan).

It may be a scaling issue, but if so, it only appears to affect red, and I've looked very closely. Refer to the "sharp" thumbnail as a point of reference. Everything but red is razor sharp.

- Anonymous

Does your TV have the equivalant to Samsung's PC-DVI setting in the "Edit Name" configuration menu for your inputs? If your TV designates a specific HDMI port for DVI conversions, you may wish to check for such a thing. Setting it to that usually disables all enhancements and makes the display act properly with GPU generated DVI signals.

It has an "edit name" feature, but it doesn't seem that it does anything other than attach a name to the particular interface. All the features that screw around with the image seem to standalone.

I wrote a review for Vizio's site, but they only post absurdly glowingly positive reviews. They simply disregarded mine:



- Anonymous

On any TV that has options like Edit Name, the one labeled DVI-PC (or HDMI-PC) is the one you want to select. That specific setting actually disables all special effects and puts the monitor into Standard mode. I would try it. You may be surprised. On Samsung TVs for instance, you must do this. You have to use the connection to the slot marked "HDMI/DVI", and then select "DVI-PC" under the Edit Name function in order to get proper passthrough.

One thing to keep in mind is this: LCDs cannot become blurry except under three situations:

1) Signal degredation. Usually caused by EM/RF interference. HDMI is especially prone to this, but in the case of HDMI you don't get blurriness, you get "sparkles" and random picture dropouts.

2) Stereoscopic 3D images are used without proper eyewear. CRTs have this issue too.

3) You're using a VGA (analog) input and the phase shift is greater than standard tolerances.

The red shift you're getting is a signal that is being distorted, and pretty severely. Notice the "sharp" images. Notice how they're literally just the pixels taken by the letters. The others are letters with "shadows" around them, or pixels of the same color subset (but darker), making them appear blurry. This is a signal distortion. It can occur either inside the TV or at the source component. If it's inside the TV you have one of two things going on - either your signal is distorted by the TV's picture enhancers, or one of its ICs is suffering a malfunction/loose solder joint.

The distortion you show on the red appears from what I can tell to be subpixel interpolation, a motion compensation technology employed by most modern LCDs. Non-native resolutions almost always exhibit this phenominon, though usually only if the scaler double dips, as mine would if I didn't disable the scaler on the 3870 itself. At native resolutions, this should never happen unless a motion compensation (interpolation between frames) occurs.

I'm going over your manual right now. I'll list the things that stick out at me here for you to go through and check (though I assume you've done most of them, you may have missed one or two).

1) Color Temperature: Select Computer, which will put the monitor at the 9300K setting as any standard computer monitor uses. This one's easy to miss. If set to Warm/Normal the temperature is set to 6500K, which produces much higher red tones, but leaves the blue/green intact.

2) Color Enhancement: Most people leave it on Normal. Since you said you turned all this off, I'm assuming it's Off.

3) Noise Reduction: Should always be Off unless you have severe image distortion otherwise.

4) Sharpness: Only useful for analog inputs, such as VGA. The default position is fine here (or off if the monitor supports that setting).

5) Color/Tint: If you're like me, you left this alone. I'd double check to make sure that the Red isn't shifted too high. You never know - those little gremlins will always find a way into a computer and change something from what it's supposed to be.

Anywho, there it is. You either have distortion (not as likely), or an enhancer is still active (Color Enhancement may be set to Green/Flesh, which enhances the Red tones a lot). Here's hoping that there is nothing physically loose inside that TV. That'd be a royal pain to get fixed (and hard as hell to diagnose).

Nope, first thing I did was turn that, an essentially everything else, off. I am familiar with that particular setting. It just fouls up the colors, but has no effect on the blurriness.

I keep meaning to check with Vizio, but every time I get home in the evening I forget.

- Anonymous

Does it have a vga input? my experience with 2 hdtv sets is night and day using the pc input vs HDMI. the VGA doing 1920x 1080 perfectly while HDMI does it but has scaling issues?(off a PC with a native HDMI port)

It has a VGA port, but I don't think it supports 1920x1080 resolution. Based on your suggestion I may give it a try...

- Anonymous

VGA can drive a 1920x1080 screen (I drive a 1920x1200 screen over VGA on occasion), though if there's some kind of limitation inside the monitor then I guess that'd be a downer.

Yeah, the limitation (if it exists) is in the monitor...still need to check. I can't, however, find my DVI-->VGA adapter and I've temporarily misplaced the manual (and too lazy to just go download it). With a really fast RAMDAC VGA can theoretically support higher resolutions than single channel DVI. I run 1920 x 1200 over VGA at work.

Upon careful inspection the problem also exists, but to a lesser degree, in blue. I can detect a very tiny bit of it in pure green, but very little. Pure colors are the worst; even saturating a color channel, so long as there's another channel right next to it (like green + red) results in less bleed.

I suspect the color processing system inside the TV is doing this intentionally and Vizio hasn't provided any means to really, truly, completely, turn it off.

This characteristic also makes it almost impossible to properly color calibrate by any means at my disposal. The response curves get all messed up at the extremes of saturation.

- Anonymous

Wow, that sucks. Yeah, purely digital signals, unless distorted by interference or an enhancer should be pixel perfect, even on a TV. TVs are simply monitors with bigger pixels these days, only with more bells and whistles to get in the way of a good viewing image (think: videophileitis vs. our audiophile debates here).

I mean, they're LCDs. They're already the color they need to be, no more, no less. Why on earth would I want to screw with the color? Color temp, yes. Color, no.

Anon, can you try a test for me to check and see if you have a color bleed (read: design flaw) problem? Turn your brightness to max. If the colors bleed even more noticeably, then I'd find a new set pronto. Regular backlighting does present a color bleed problem on occasion depending on panel type (most severely associated with PVA/MVA panels actually, like mine), while LED backlighting does not usually.

Here's hoping I'm wrong with your set.

To continue the sidetrack... my grandfather did the same exact thing. Wore glasses for 70 years, got laser surgery and never wore glasses again for the last 4-5 years of his life, and loved it. If I could afford it, I'd do it in a minute. Doing photography with glasses is a huge PIA, especially events.

Backlight brightness doesn't affect it. The "color" control, basically a saturation control, does. If I turn it down to zero, turning the display in to a 32" flat panel black and white monitor that would have been absolutely stunning in about 1993, the problem goes completely 100% totally away. It gets progressively gets worse as I turn the color setting back up.

- Anonymous

I contacted Vizio tech support and they told Valued Customer me:


OK, I'll try it, but I'm not expecting much. Maybe the rep didn't notice I posted pictures? I included a link to my post.

- Anonymous

Heh. When was the last time tech support showed more than an ounce of self initiative? I mean, seriously. It's all about how fast you can CTRL-V and type in an email address and hit send these days.

So with the color saturation at its default position, you get the reds, but not the others and with it effectively off, you get no defects at all (but are stuck with a 1993ish monitor at that point)? I'd call that a defect for sure. Unfortunately, it's a defect in the TV itself, and not from the source inputs. How long's the warranty on these?

It has a one year warranty. The issue is noticeable in blue at normal saturation levels, but not in green without magnification. Blue isn't as bad as red.

I suspect this is a "feature" not a defect.

- Anonymous

It sure worked for me, Even did DVI to VGA from my macbook pro once... suprised that a native HDMI does not fill the screen properly after going thru the effort of getting sound on the HDMI port. was fine for TV but a little ugly for things like web browsing again VGA was was pretty much perfect.

This is usually related to overscan and/or the TV's scaler being invoked. Unless a specific setting on the TV is used, the incoming HDMI signal is downscaled, then rescaled back up to the TV's native resolution, resulting in massive blurriness/pixelation.

On my monitor (Westinghouse 24" LCD, L2410NM), unless I have the "Overscan" checkbox enabled in OS X (under Options in the Displays prefpane), I get black bars around my entire screen. Overscan forces the image to use the full area of a monitor, and having it unchecked is only useful for CRTs, where the "full" area would result in part of the picture being outside the visible glass boundaries. On Windows using ATI's Catalyst Control Center, you have to navigate to the video setting that is the "Scaling" slider and move it to 0% (it goes from zero to negative numbers), which is the same as selecting Overscan.

I'll be the first to admit that HDMI's spec and implementation have been disastrous since its inception, and it's only going to get worse, not better. If you go to HDMI.org, you'll soon learn that they are now forbidding companies that sell HDMI cables from using the HDMI version spec on their labeling, and instead using the crappy "Standard", "High Speed", "Ultra High Speed", and the three aformentioned "with Ethernet" denotors to distinguish between cables. So now the consumer will have even less information available on the cables they buy. And you know the two companies that are involved in this one: Sony, and Monster Cable. Those are the ONLY TWO that used that system already. And trying to figure out which cable is actually a good one from them was nigh impossible as no real specifications were ever given out.

The industry, and just about every industry as a whole lately has been "all about them, and fuck the consumer". Go ahead, look around. Tech support? Uses minimal info, usually non-english native speaking people outsourced from India. Manufactured goods? Provides either non-useful (read: non-informative) info, or jargon that is so complicated as to be frightening to say the least. And the FCC/FTC are allowing it to happen unhindered, making life miserable for the average consumer trying to get good....goods.

Oh, and if you're planning on buying a receiver/AVR soon, don't. Later this year, HDMI 1.4 enabled devices and components will start appearing en masse. Anything regarding HDMI 1.4's specifications that you might want to make use of that aren't on today's AVRs and equipment will NOT be backward upgradeable. So sit tight on the purchases for now, unless you have no interest in the new HDMI 1.4 features (and their associated headaches).

Oh, and Anon, I'd call Vizio and ask them what scaler their TV uses. If it's the Anchor Bay 1010 (and not the 1018, which is OK), then you have a scaler that got horrible reviews in nearly every AVR that it was put in (most noteably the Yamaha 28/2900 and 38/3900 series), mostly for its very poor image quality.

Competition is great and all, but when standards aren't standards anymore, then you fall back to the one truism: Garbage in, Garbage out. And don't get me started on how high the failure rate is for ROHS Compliant goods with their lead-free solder. Somebody tell me, what good is going green when doing so causes more goods to be recycled due to failures and defects?

I was extremely surprised* to discover that all the resetting Vizio suggested had no effect on the problem whatsoever, except for making the sum total of image problems significantly worse by reintroducing all the idiotic defaults.

Fortunately made a list of all the settings values I was using.

- Anonymous

* By which I mean "not surprised in the least bit at all."

Based on the symptoms and what I can figure out about signal encoding (again, something about which I know relatively little), this may be an issue with the TV using YCbCr chroma subsampling, which may reduce the horizontal resolution of the color channels relative the luminance data. In 4:2:2 subsampling, the color data are transmitted at 1/2 the horizontal resolution of the luminance data, which seems likely to yield image artifacts very similar to those I've observed.

I'll finally have a chance to chat with Vizio tomorrow and if their support staff have sufficient technical training, I feel I should be able to get to the bottom of it.

If YCbCr 4:2:2 encoding is the problem, I need to figure out if the computer, the TV, or something else is dictating this. There simply may not be a solution.

- Anonymous