Posted by Marc Martin on
URL: https://www.shado-forum.com/UFO-on-Family-Room-HD-tp1510555p1510594.html

> I believe you; what I meant to establish was whether HD would be able
> to replicate the original film resolution to the point where we could
> watch at this quality on our own TVs - if this makes sense :-}

I don't know what the resolution of the original film
negatives are. Best case with modern-day film is apparently
around 4000 x 3000 pixels, but as has been said before, UFO used
film from 1970 and was not necessarily the best grade of
film available, nor did they probably bother to focus
so accurately to take full advantage of the film resolution.
The frame captures I have from the 1080 x 1920 broadcast of
Space:1999 look a bit blurry at that resolution, so I assume
that the high definition version exceeds the resolution of
the original film.

> Isn't film a different size ratio to either 4:3 or 16:9, so wouldn't
> some cropping of the original image be necessary in both cases to
> make it fit onto television screens?

Well, I think film is 1.37, which is very close to 1.33 (4:3).

> I'd be interested to hear the pseudo-surround though! Why do you
> think this is worse? Have they added extra sound effects or
> something? :-/

No, they've added echo, and essentially to get a "stereo"
effect it sounds like someone has turned the balance control
from left to right. It's quite annoying, and can be found
on the English track of the Japanese UFO DVD releases.

> If this is so, then why can't they release an HD DVD version using
> the uncompressed SD remaster as the source, to be able to see the
> higher quality resolution?

They could indeed release an HD DVD using the old SD masters,
and utilize less compression to give a higher quality picture.
However, I doubt that they'd bother, as they'd probably only
see a market for a release that is truly mastered in HDTV.

> I'm sorry - I did say I was completely ignorant about digital
> technology! As a consumer though I'm interested to understand how
> HD is meant to be an improvement over SD. Seeing what you've just
> said - that we can't even see the SD version at it's best - makes
> me wonder even more what the point of HD is... :-/

Well, today everything is compressed -- if you listen to an MP3
file, it has been compressed. If you view a JPEG file, it has
been compressed. It just makes sense from a quality-to-file-size
ratio. All things being equal, a compressed HDTV picture will
look better than a compressed SD picture.

> Okay - so with reference to UFO on ITV 4, although they are an SD
> digital channel they are somehow broadcasting the old analogue prints
> converted into digital - they can't be showing the DVDs because the
> picture is so rubbish!! If they are then compressing this digital
> signal even more, doesn't this mean what we are watching now is worse
> in quality than these same prints when they were broadcast over
> thirty years ago?

It could be -- the digital compression does degrade the picture, but
30 years ago you had ghosting images or noisy cable feeds.
You're just trading one set of degradation for another. On my
cable system, I've compared the analog versions of channels
with the digital conversions of those same channels, and there
are certainly reasons to prefer to the analog versions. However,
the HDTV versions of these channels are better than both the
analog and digital SD versions.

> Hang on - are you now saying that compression doesn't make much
> difference in picture quality? Or only in ways that the average
> punter wouldn't notice? Or that there are acceptable levels of
> compression? Help, I'm even more confused!!

I think compression is ALWAYS acceptable, it's just how MUCH
compression is used is the issue. There is too much tendency
to cram too many episodes onto a DVD, or too many channels
onto a cable/satellite system. With a reasonable amount
of compression, the nobody is going to complain about it.

> Oh dear, yet *another* factor to have to consider when buying new
> equipment ;-O Could you clarify what you mean about a difference
> between the source and TV in terms of resolution and why it matters?

Well, in the good old days of analog CRT systems, your broadcast
channels and video systems assumed that you had a certain number
of lines of vertical resolution (576 lines for PAL, 480 lines for
NTSC). And the TV's you have were designed for that, too. Now,
we have cable systems and video discs that put out 480/576 lines,
or it might put out 720 lines or 1080 lines. And you have TV
sets which might have yet another resolution -- I own an HDTV
which has 786 lines! In order to fill the screen, the TV or cable box
or DVD player must now scale the signal to fit the TV, which
can cause further degradation. Just try running your LCD
computer monitor at something other than its native resolution,
and you'll see the same kind of degradation. Certainly
the best quality is going to happen when viewing the
source material at its native resolution, and if not,
higher quality scaling will produce better results.

> So it really is all down to size?

Size and distance. For every size of television screen,
there will be a distance where one cannot tell the
difference between SD and HDTV. So if you've
got a large screen or are watching from a close
distance, you're more likely to notice the
improvement.

Marc