Need some quick clarification on Hitachi "Stretch Modes" and Tosh "Resolution" (1 Viewer)

[Jack Briggs]

Ever thought of going back to a direct-view set, Rain? Say, a Sony KV-40XBR800? A KD-34XBR2? Or one of the Toshibas or Panasonics? The edge-enhancement artifacting is much less noticeable on direct-view sets. Would you be willing to pony up for the Loewe Aconda (considered by some reviewers to be the best consumer display short of a Runco, Vidikron, or Madrigal CRT-based front projector money can buy)?

 

[Rain]

Would you be willing to pony up for the Loewe Aconda...?

If money were no object, I would "pony up" for the best display device money could buy. Alas, I'm just a working stiff, so I guess the answer to that one is also "no."

 

[John Doran]

mike,

the picture you took of the hitachi is of a different test-pattern than that of the tosh: you did the 100 for the 'tachi and the 200 for the tosh.

it's also difficult to know what to make of these comparisons wthout knowing the relative calibrations of the sets being compared - i.e. calibrated or not? contrast? brightness? sharpness? etc.

just a thought.

- jd

 

[Michael TLV]

Greetings

The first image from the Toshiba is off a calibrated unit.

I can vouch for Mike on the Hitachi shot in that it is accurate and looks the same even from a fully calibrated Hitachi unit for the 6.75 mhz circle.

It gets the message across.

Regards

 

[Steve Schaffer]

The Hitachi I had was the UWX10B, not the SWX line which is afaik a much better set.

The "bad stretch mode" was the variable stretch mode, probably Zoom 2 for 4/3 on the current models. This is the mode that stretches the right and left edges more than the center. Any of the modes that don't involve a variable stretch are gonna be the same on any mfgs sets--a straight sideways only stretch uniform in center and sides, or a uniform zoom which stretches both horizontally and vertically--fills the screen left to right but chops off the top and bottom of the 4/3 frame.

The variable stretch is the only one that's going to be handled differently by different mfgs.

As far as I've been able to observe, Hitachi and Mitsubishi take a 4/3 picture and leave the center alone but stretch the sides more, with no vertical zooming so there's no picture lost off the top or bottom. This leads to a pretty extreme funhouse mirror effect.

Sony's variable stretch does stretch the center but only a little. They also do a bit of vertical zoom in combination with some compression at the top and bottom. There is more stretch at the sides than at the center, but since there's also a little stretch in the center and some overall vertical zoom, the side stretch isn't nearly as extreme as with Hitachi's or Mits's method.

Toshiba and Pioneer are also sorta like the Sony, some say they do it even better.

I have no idea how sand gets between screen layers, luckily I don't have this on my 1 year old Sony. On the Hitachi I had what looked like an irregularly shaped puddle of oil about a foot by a foot and a half trapped between screen layers. I never noticed it until the day they came to take it away, but it was there and visible with the set turned off if you got right up close to the screen. If I hadn't returned it for other reasons it wouldn't have bothered me as I never saw it when watching the set.

I don't really mean to knock Hitachi--variable stretch modes aren't important to lots of people, Rain included, and the other problems I had with it could very well not exist on current models. I had an analog Hitachi 53SBX59B for 2 years (still do, actually) and it was an excellent performer. Letterbox images were 1cm higher on the right than on the left, but it was a uniform screen tilt that I never would have noticed on a fullscreen image, and since the geometry was otherwise excellent I ignored it. It also had some wierd semitransparent lines about 2 inches wide running vertically on the left and right sides, but only when displaying murky greenish or bluish colors (i.e. underwater scenes in Das Boot). Looked like the "raster ringing" the first Mits. 46 inch widescreen sets had.

I don't think anyone makes an absolutely perfect rptv, not even the Pioneer elite. They all seem to have one or more issues that one has to decide whether or not they can live with.

 

[John Royster]

Am I the only one who sees something very wrong with that hitachi picture?

There has to be something going on there other than SVM. other EE possibly?

 

[Jack Briggs]

Michael TLV: Thank you for the in-depth reply to my question (as well as for your other excellent posts). It was very interesting to read! Do you think Toshiba will respond to calibrationists (and magazine reviewers) who comment on this issue and allow for direct access to the color decoders by midyear, or by next year's models? Thanks again. JB (Wow, Samsung sets have gone that high above gray, have they? I bet they look blue!)

 

[John Doran]

so let me get this straight - despite the fact that the test patterns for the toshiba and hitachi are not the same (i.e. the horizontal and vertical resolution wedges - the tosh is 200 and the hitachi is 100); despite this difference, the 6.75mhz circle is the same for both?

just wondering.

is it also a feature of the toshiba sets that they are as dark as mike's picture suggests, and the hitachi's that they have such an incredibly bright band through the middle of the picture?

i'm currently in the market for an RPTV, and, quite frankly, both the hitachi and the toshiba pictures in Mike's post look bad to me - the toshiba for it's dimness, and the hitachi for that nutty band of brightness right through the middle...

thanks for the help.

- jd

 

[Michael TLV]

Greetings

Have you ever looked at the two TVL patterns before ...? Yes they are the same when it comes to the 6.75 circle.

Dimness = contrast. I'd never base a buying decision on a picture of an image being dim.

Often dim in the showroom = still too bright in the home.

Emphasis on "showroom."

Regards

 

[Rich Chiavaroli]

john doran -

You can't base the dimness/brightness on picutures. What was the appature size and shutter speed of each picture? How much are those lights in the background affecting the picture? Was a tripod used so they could get proper light exposure in that area or did they have to take a darker exposure to keep the picture sharp?

Photographs generally never refelct what the eye sees unless you're in an extremely well lit area, or if someone takes the steps to try to show what the visual light level is. These pictures were taken for what appears to be the sole purpose of showing the effects of the toshiba upconversion. They do a good job of that, but you can't form opinions on the light levels based on this.

On top of the issues of the actual picture, you have the even bigger issue of how your computer displays the pictures.

 

[John Doran]

michael,

Have you ever looked at the two TVL patterns before ...?

no, i haven't.
rich,
what you say strikes me as intuitively correct, which then begs the question - how useful are those pictures posted by mike on the previous page in determining phenomena such as comparative resolution-loss as between the sets? if there's so many variables in play - not even considering the obvious difference in brightness/contrast or whatever between the pictured sets - how much support can those pictures reasonably be thought to lend to the claim that hitachi's 540p upconversion is superior (less lossy) than toshiba's?
i mean, while i would certainly never think of myself as making any ultimate buying decisions based on some pictures or the interpretation of those pictures posted on a forum, the fact of the matter is, many people rely on these forums for a wealth of technical knowledge about HT which unavoidably affects the way at least some of us perceive the audio and video of the components we audition, whether or not we're aware of it.
i just don't want to go to audition RPTV's while in the grip of erroneous or unwarranted conclusions concerning the abilities of the sets i'm going to compare. you know? if you believe your supposed to see more "smearing" in the toshiba sets as compared to the hitachi's, then you're more likely to see it...
anyway. thanks for the help.
- jd

 

[MichaelFusick]

Yes, 6.75mhz is the same.

It was not calibrated, and set at about 50% contrast I think.

I don't know where or why those bright bands are there. Somthing from the camera I think. It was a cheap Sony digital camera on the showroom floor. Nothing speacial.

MichealTLV is right, both sets will be plenty bright for home viewing.

CC just had a serious light upgrade, and it is BRIGHT! Hitachi's sell well becuase they are brighter than other sets and stand out I think. They do look brighter on the showroom. Usually you just have to turn them down more, for a Hitachi owner, 40% contrast is used by some with new sets, so I would say they are plenty bright.

 

[MichaelFusick]

if you believe your supposed to see more "smearing" in the toshiba sets as compared to the hitachi's, then you're more likely to see it...

Yup,

I think once you know that it is there, and that you can't fix it your all done.

As a videophile I strive to make my display as best it can be. I used the joke, but probably would build a tank around my RPTV and submerge it in water if I thought it would help my picture.

If you never knew about it, or that it was there I think people would never think twice about it. Atleast for me and my personality, once I found out it would bother me to no end.

 

[John Doran]

mike,
my problem is not with actually seeing this alleged smearing or resolution-loss or whatever it is - it's with only thinking i see it either because that's what i've read other people say they've seen, or because that's what the specifications suggest one should see. you know?
the problem for me is that (A) i don't know enough about the technical specifications of 540p upconversion in general or 540p upconversion as it is implemented in hitachi and toshiba sets to enable to me to see (i.e. do the math) for myself that the result of a particular example of 540p upconversion ought to result in resolution loss;
and (B) i don't know how many of the people who claim to see the smearing are actually seeing it or only thinking they see it because they themselves have been convinced that they're supposed to see it.
my problem with the pictures you posted is that they're of limited use as evidence for your claims, since along with the difference you note between them i see a whole host of other differences, and i have no idea how all the differences relate to one another: are the bars in the tosh 6.75 circle less visible because the set is so dim? are those in the hitachi so much more visible because that set is so bright? were the pictures taken with the same camera? would it matter if they weren't? if there is resolution-loss, is it visible at all in real-world viewing, i.e. when i'm watching movies?
that's all. i want to go and check out RPTV's with as few presuppositions as possible.
thanks again.
-jd

 

[MichaelFusick]

A resolution test is black and white to me.

Either you can or you can not clearly resolve the fine lines in the test pattern.

Regardless of the reasons, if you can you can, and if you can't.

Those test patterns are a way of measureing the given resolution of an RPTV from a DVD source. Nothing more, nothing less.

The idea is to be able to see the lines clearly. I have seen more than one Hitachi clearly display them. All this means is that the Hitchi can clearly display them.

The weight one gives to these issues is up to the individual, I think MichealTLV reason for pointing them out, and the reason why others too will discuss them is not for putting down toshiba, rather make people aware of them so that these issues get fixed.

Upconversion is only a single issue. There should be many more things considered when purchasing and RPTV. Toshiba does many things well, including the stretch mode which most people agree the Hitachi does not do well.

 

[Michael TLV]

Greetings

One can nit pick any thing to death if you are so inclined. At which point, believe nothing and go find your own answers.

We are only trying to help and no is paying us for our time trying to fish up answers ... If you choose not to believe it ... it is fine.

There are no evil agendas here or vendettas against certain brands of TVs.

Take everything into consideration and make your judgment then. Nothing is perfect ... so you have to pick which things you can live with ... or tolerate.

People have an uncanny ability to see or not see anything they want.

Regards

 

[John Doran]

i agree. i assumed neither malice nor any vendettas.

nor do i want to nitpick.

i simply want to be in possession of as much uncontroversial information as possible before i go and check out RPTV's.

i was merely making observations both about the information presented on this thread and the way it may affect human psychology. that's all.

'nuff said.

- jd

 

[Rich Chiavaroli]

john -

From what I've seen in stores, you're more than likely not going to be able to tell the difference when you watch a DVD. Especially from a normal viewing distance. Yes, it will probably be a slightly "softer" picture, but are you going to notice this unless you're really really looking for it? Probably not.

My opinion from what I've read and seen is that yes, there is some loss is resolution, but it isn't effecting my decision on which TV I'm going to buy. I've actually ruled out the Hitachi due to other reasons, and Toshiba is on my short list.

Now if your primary concern is absolute picture quality with DVD movies, then this might be an issue. For me, I'm more concerend with stretch modes and how well the set handles non-HD TV. I can't afford to buy a set for just DVD's, and there's not enough HD content in my area for me to not make 4:3 cable TV viewing an important issue in the buying decision.

I think Michael TLV is just throwing the information out there so it's available. I've read some positive comments from him about the Toshiba sets also. (thankfully) He's seemed to be the voice of objective commentary here that many of us need.

 

[Rain]

Returning briefly to the "ghosting" issue...

Last night I tried a little experiment. I hooked up the DVD player so I could do a side by side comparison between the RPTV and my old crappy direct view set.

Interstingly, the "ghosting" was visible even on the direct view. Granted it is not as obvious likely due to size and resolution, but it was there.

I'm beginning to wonder how much the player is factoring into this equation.

 

[MichaelFusick]

Yes,
EE from the player can effect things.
Panasonic DVD players are great for the money, but they have EE features that can cause slight ghosting with different upconversion methods. Panasonic RP62S ghosted more than an interlaced sony DVD player on the Hitachi I played with.
Here is some more talk:
http://www.avsforum.com/avs-vb/showt...8&pagenumber=2
Improper sharpness can cause "ghosting" too. Where there is white halo around things.
Convergence can cause ghosting.
Also lose blue focus causes a halo too.
There are so many causes and different types that without more info and experiments it tough to figure out what is going on. This is a good topic for discussion in my opinion.