DTV transition "Soft test" on 11-20-08 in Chicago

[JohnVF]

Update...I just spent an hour at a place that creates the masters for TV broadcast commercials, because we were stuck as to what was happening when we were converting our HD masters to SD on their conversion equipment. If we were having issues there, I can only imagine how bad it must look with a set-top conversion box. What a mess.

[wa2ise]

Originally Posted by zenith2134

SD analog blows dtv away. For this simple reason: It is not compressed.

Odds are that analog signal was delivered to the analog transmitter site as a DTV signal, decoded and downconverted to 525i analog, and fed into the analog modulator and transmitter.

[Chad Hauris]

In my experience I have gotten so much better reception with digital (converted to analog and watched on CRT TV's). I used to get so much ghosting and weak signal issues with analog, when the antenna blew down 5 years ago or so I never replaced it and went with satellite....I now am enjoying over the air TV thanks to digital.

The picture quality of an HD signal downconverted to analog on a set-top box is amazing to me...looks even better than a DVD. To me the signal quality really brings out the best especially in old TV's.

I think in some areas stations may be waiting to go to higher power on digital which may bring better digital reception.

[Carmine]

I think that to label people who favor a free-market solution as "nit-pickers" is pretty shallow. ATSC and NTSC have been broadcasting side-by-side for years now. When free NTSC is no longer worth the extra work of conversion from digital, or the electricity to run the transmitter (vs. advertising revenue), broadcasters will shut-off the power. That simple.

What we now have is a cluster-F courtesy of corporate lobbyists who purchased the required votes to force the FCC into setting a date. Imagine if politicians were this openly owned by corporate interests in 1950? We'd all have motorized spinning discs on our 10" color TVs! I suppose they know that circa 2008, we're all too addicted to "digital quality" to give a damn about things like a free-market.

Having experienced the same thunderstorm digital shutdown, while NTSC continued without any failure, this digital broadcast system is obviously not ready for prime-time. (LOL, I kill me )

[peverett]

The problem that I have seen is not the picture quality. In good reception conditions, it has been my experience that digital is better than analog, even on a standard definition set.

The issue that I have seen is when non-ideal reception conditions occur, such as thunderstorms, etc. From what I have seen analog delivers a usable signal(I do not claim perfect) far after DTV has completely crapped out. This may not be important to Chris(who lives in CA where these are rare), but is very important to anyone east of the Rockies depending on broadcast TV for weather info, especially people in tornado alley. It is my belief that this is more than a signal strength issue-it is a basic weakness of DTV. This is the reason I believe completely scrapping NTSC analog TV is a big mistake.

As far as the picture quality, try watching a standard def picture on a TV capable of true HDTV-it looks horrible and out of focus.

As far as the converter boxes, these seem to vary greatly in quality, with the RCA sold by Wal-Mart being the worst I have expericenced.

[Carmine]

Originally Posted by peverett

As far as the picture quality, try watching a standard def picture on a TV capable of true HDTV-it looks horrible and out of focus.

I'll back that up, having spent some real time watching a HDTV recently. Whatever the reason for this, I don't know, but I imagine it's why you have some many people popping up to say "once you've watched HD, you'll never go back."

I pretty confident that if you compared the TV this HD set replaced side-by-side with a non-HD signal, the older set would be much better. On the HD Channels, the picture was better than NTSC, but "awe-inspiring"? Naw... Lots of shimmer effect in highlights.

The ONLY place where the HD signal blew away what I've seen of a ultra quality NTSC picture was during a live car auction shown on some cable channel. Very sharp, colors look right, great detail.

So I will concede it is possible for HD to beat NTSC, but the conditions are rare and hardly worth the bother of a new set IMHO. I suspect others would have felt the same way, thus the mandate.

[mr_fixer]

Originally Posted by Phil Nelson

Can't you have a friend or relative apply for coupons and give you the cards when they arrive?

Phil Nelson

Probably, but that is not the point. they had figures on how many converters they needed, but the manufacturers didn't make enough, it is like they didn't care. They are probably making more money off of new TV's and don't won't to waste the effort to worry about a government program. Well i won't worry about watching US tv. I have the high speed internet and i have veoh and youtube and i find more interesting stuff coming out of the UK than America can produce. Logan

[ChrisW6ATV]

Originally Posted by JohnVF

I just don't get judging a technology when you don't have the proper means to actually see what it's capable of. I don't judge the capability of LP on a BSR changer....no I'm not calling SD sets BSR changers, they're excellent at analog signal reception, but they don't have the ability to extract what digital TV is all about. The converter box is simply trying make something do what it wasn't designed for. I would think that those converter boxes you unfortunately are having to buy are down-converting the HD signal to SD...of course that's going to look terrible. it looks terrible when we do it here at work on very very expensive electronics. But digital looks stunning on my TV. Standard looks like I'm looking at the film we shot through gauze.

Thank you for some very good points from an industry insider.

[ChrisW6ATV]

Originally Posted by peverett

As far as the picture quality, try watching a standard def picture on a TV capable of true HDTV-it looks horrible and out of focus.

Read the quote above for a couple of reasons.

Also, there are some HDTV displays that can show a pretty good SD picture. The main reason that SD looks "horrible and out of focus" on an HDTV display is because SD/analog NTSC IS "horrible and out of focus" by comparison with good high-definition video. Most of the problems are the basic limitations of the analog/NTSC signal itself. This can be obviously seen by comparing such a signal on an HD display, to a DVD on the same display. DVDs are basically the same resolution as standard analog NTSC, but not subject to all the problems of composite OTA analog TV signals.

I truly doubt you would actually see better detail or color quality on an analog TV than with the same signal on a good quality, well-adjusted HD display.

[andy]

I think part of the problem of NTSC on a HDTV is that a lot of HDTVs do a poor job of scaling NTSC to the TV's native resolution. They tend to overprocess it which gives it a smeared flat look.

[wa2ise]

Originally Posted by andy

lot of HDTVs do a poor job of scaling NTSC to the TV's native resolution. They tend to overprocess it which gives it a smeared flat look.

Back in the early days of TV cameras, it was found that they could set the focus of the image on the pickup device (various camera tubes then) a little too sharp, so that the resolution of the image would violate Nyquest sampling theory. A fancy way to say that the scan lines, in the vertical direction, act as a digital sampling system. Like a scan line being like a pixel in the vertical direction. Okay, if you aim the camera at a set of venetian blinds on a window, and the focus is too sharp, you get "alias" effects in the vertical direction. Those look here like wide area dark and bright bands, which don't exist out in the real world at that window.

However, it was found that you can slightly exceed this Nyquist focus limit by about 10%, which will make the image as seen on a TV set look sharper, with only a little bit of aliasing. This is called "Kell Factor".

A few years ago I suggested that this Kell factor could be made use of in downconverting HD to SD resolution, and the place I worked for at the time filed a patent application. But the place hit hard economic times, and I don't think they followed up on the patenting process...

Downconverter boxes should use Kell Factor.

[jhalphen]

Hi to All,

WA2ISE, you wouldn't have been working for Faroudja Labs perhaps?

They were known for extracting pretty incredible pictures from standard composite signals (PAL & NTSC) for use with TV projectors (line doublers and quadruplers).

I personally saw a demo at the IBC Broadcast show in Brighton (UK) where a 1"C VTR used a Faroudja box as an Encode/Decode processor. The color bars upon playback looked like rock-stable, gorgeous component video and yet standard NTSC was the input.

BTW, Yves Faroudja was a French engineer. When he saw no future for his ideas in France, he emigrated to America. Also made quite a bit of money in the heydays of the company (1980s).

Best Regards

jhalphen

[MRX37]

I think, with minimal compression and good color matching, HDTV does indeed surpass NTSC. If the signal is strong enough, reception should be fine, storm or no storm. My main beef is with weak channels. On analog, you can at the very least hear them, or get a watchable picture. HD is all or nothing, and that's really its only significant drawback.

The compression artifacts are the fault of the broadcastors, not the format itself. DVD uses the same format, and when transferred from a high quality film source, the picture is excellant.

Nowadays, all analog stations are broadcasting downsampled DTV converted to analog. On an analog set, you wouldn't be able to spot the difference unless too much compression was used.

In a nutshell, the idea is sound, but the way it's being executed is flawed.

[wa2ise]

Originally Posted by jhalphen

Hi to All,

WA2ISE, you wouldn't have been working for Faroudja Labs perhaps?



jhalphen

Not for him, but I did work quite similar (chroma luma separation, adaptive line and frame comb filters, interlace to prog scan conversion and such) at the old RCA Smirnoff Lab in the 80's. And more of this at MicroLinear, a fabless analog semiconductor house. And have invented 13 patents in this field, assigned to the companies, but I still get bragging rights. Looks good on resumes. Link to a list of my patents ->http://pw2.netcom.com/~wa2ise/radios/patents.htm

[Snade]

In areas like Chicago there are tens of thousands of analog TVs used in spare bedrooms, basements, apartments, nursing homes, kitchens that use rabbit ears and may have average video reception but excellent reception of sound. Many of these TVs are used in the background, meaning the viewer may be working in the kitchen and listening to the TV show and occasionally glancing at the picture. I expect many of these, on the conversion date will not be prepared with converter boxes and if they do try to install a converter box, they will have trouble with bad digital video reception and very poor audio reception because digital requires proper and special antenna installation.

I expect the press will report on this problem after the conversion date, but if this group will have enough clout to change anything, I expect not.

Snade