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Difference in lines of resolution more obvious on computer..

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Anonymous
September 3, 2004 12:33:19 AM

Archived from groups: rec.video,rec.video.desktop,rec.video.production (More info?)

I was reading reviews of the Sony DCR-HC30 and DCR-HC40. It indicated that
the 30 had 500 lines of resolution and the 40 up to 530. If these are
rendered to NTSC format which is 720x480, at what point woudl the extra
lines of resolution be visible and result in a better quality picture? The
only time that comes to mind is while the editing/viewing on a computer. If
it is intended to be burned to a DVD and viewed on televisions, would the
additional lines matter or improve clarity in anyway since they are
converted to 480 at that point anyway?
Anonymous
September 3, 2004 5:28:27 AM

Archived from groups: rec.video,rec.video.desktop,rec.video.production (More info?)

Bob Evans wrote:

> I was reading reviews of the Sony DCR-HC30 and DCR-HC40. It
> indicated that the 30 had 500 lines of resolution and the
> 40 up to 530. If these are rendered to NTSC format which is
> 720x480, at what point woudl the extra lines of resolution
> be visible and result in a better quality picture? The only
> time that comes to mind is while the editing/viewing on a
> computer. If it is intended to be burned to a DVD and viewed
> on televisions, would the additional lines matter or improve
> clarity in anyway since they are converted to 480 at that
> point anyway?

You are confusing "lines of resolution" (aka "tv lines") with
scanlines. See <http://www.google.com/groups?selm=1993Mar24.
133013.27882@imax.imax.com> for a longer explanation.

You might also want to take a look at this article by Peter Utz:
<http://videoexpert.home.att.net/artic1/201res.htm&gt;.

--
znark
Anonymous
September 3, 2004 5:29:50 AM

Archived from groups: rec.video,rec.video.desktop,rec.video.production (More info?)

In message <ch86pe$no1$1@plaza.suomi.net>, Jukka Aho <jukka.aho@iki.fi>
writes
>Bob Evans wrote:
>
>> I was reading reviews of the Sony DCR-HC30 and DCR-HC40. It
>> indicated that the 30 had 500 lines of resolution and the
>> 40 up to 530. If these are rendered to NTSC format which is
>> 720x480, at what point woudl the extra lines of resolution
>> be visible and result in a better quality picture? The only
>> time that comes to mind is while the editing/viewing on a
>> computer. If it is intended to be burned to a DVD and viewed
>> on televisions, would the additional lines matter or improve
>> clarity in anyway since they are converted to 480 at that
>> point anyway?
>
>You are confusing "lines of resolution" (aka "tv lines") with
>scanlines.

He certainly is not.

>See <http://www.google.com/groups?selm=1993Mar24.
>133013.27882@imax.imax.com> for a longer explanation.

An explanation which is absolutely wrong.
>
>You might also want to take a look at this article by Peter Utz:
><http://videoexpert.home.att.net/artic1/201res.htm&gt;.
>
And another which is wrong.

For a correct explanation see.
http://www.camcord.info/formats/, specifically in the Line Resolution
section.

And the line resolutions for the various recording mediums is given in
the table in the section below that, "Recording Media Formats".

Insofar as the OPs question, miniDV has a nominal line resolution of 500
lines which (I believe) is the figure attributed to the DCR-HC30. The
actual Line Resolution (as determined by a test card or other means [1])
is affected by a number of factors. One is the characteristics of the
particular tape being used, another being the signal processor of the
camcorder.

Sony claim a higher than normal line resolution for all current models,
of 530 which has been substantiated subject to (2) below. It is
due to two factors (they couldn't claim 530 if they could not
substantiate it):

1. Sony's HAD technology used in all their current crop
of miniDV camcorders (it was first introduced in their
DCR-TRV30 three years ago).

The HAD technology signal processor uses 16-bit sampling
and processing, all other miniDV camcorder manufacturers
use 12-bit sampling and processing. This allows Sony (subject
to (2) below) to squeeze and extra 20 or 30 lines of
resolution.

2. The characteristics of the particular recording (miniDV) tape
being used. With Sony camcorders using either Sony
Excellence or Sony Premium tapes they will achieve the
530 line resolution figure. Other types of tape may give
you less.

You may notice that other manufacturers claim either 500 or 510 line
resolution.

[1] As explained on camcord.info, the line resolution was (and
still can be) determined by the use of a test card. There are
graphic files on the Internet that can be used to produce
a test card to determine the line resolution [2]. With today's
technologies, though a test card is still used to record, the
particular figure is today (in optical/video labs) determined
not by eye, but by examining the replayed video signal on
an oscilloscope.

[2] A "Test Card Maker" program can be downloaded
from:
http://www.oodletuz.fsnet.co.uk/soft/tcmaker.htm

--
Tony Morgan
http://www.camcord.info
Related resources
Anonymous
September 3, 2004 4:24:55 PM

Archived from groups: rec.video,rec.video.desktop,rec.video.production (More info?)

On Thu, 02 Sep 2004 20:33:19 GMT, "Bob Evans"
<robert_evans_yah@yahoo.com._NOSPAM> wrote:

>I was reading reviews of the Sony DCR-HC30 and DCR-HC40. It indicated that
>the 30 had 500 lines of resolution and the 40 up to 530. If these are
>rendered to NTSC format which is 720x480, at what point woudl the extra
>lines of resolution be visible and result in a better quality picture? The
>only time that comes to mind is while the editing/viewing on a computer. If
>it is intended to be burned to a DVD and viewed on televisions, would the
>additional lines matter or improve clarity in anyway since they are
>converted to 480 at that point anyway?

First thing, "lines of resolution" isn't a measure of pixels. What
it measures is the number of vertical lines visible within a square on
the display (nowadays this is measured with electronic instruments,
not visually). Since the TV picture isn't square, the total number of
vertical lines which might be visible on the screen will be larger
(roughly one-third larger) than the lines of resolution.

Second thing, the frame size of a digital format extends outside the
visible area on most TV monitors (some can show it out to the edge).
For NTSC, that gives a maximum DV usable resolution of between 704 and
710 pixels. When you run through the numbers, that means that DV at
530 lines of resolution will need that 704 pixels to display it
without loss, with a bit of rounding filling in the remainder.

DVD resolution is only slightly smaller (704x480).

The 480 dimension is fixed -- a poor TV or other video device might
display them imprecisely, blurring the image a bit, but nothing can
make NTSC TV show more than that (in standard definition anyway).


Lines of resolution measures the apparent sharpness of the image,
*not* its pixels of resolution. Some video devices offer sharper
images than others, and if the recording medium can handle it, you'll
actually see a difference. DV is already much higher resolution than
SVHS or Hi8, let alone VHS, so 500 lines of resolution is quite good.

An analogy might help: If you take a picture which is very out of
focus, the image will be quite unsharp. You may not even see two
clear lines on the screen. Yet the DV frame size of that blurry
picture will be exactly the same -- 720x480 -- as one which is in
perfect focus, showing excellent detail.

Better camcorder technology can give you a little more detailed
imagery from the DV format. 500 vs. 530 isn't a huge difference, but
every little bit can help -- especially in poor light or other
conditions where the image detail isn't easy to see.

--
*-__Jeffery Jones__________| *Starfire* |____________________-*
** Muskego WI Access Channel 14/25 <http://www.execpc.com/~jeffsj/mach7/&gt;
*Starfire Design Studio* <http://www.starfiredesign.com/&gt;
Anonymous
September 3, 2004 10:00:11 PM

Archived from groups: rec.video,rec.video.desktop,rec.video.production (More info?)

> For a correct explanation [regarding Lines of Resolution] see.
> http://www.camcord.info/formats/, specifically in the Line Resolution
> section.
>

Thank you very much for pointing me back to that page. I browsed it quickly
earlier in my search for info, but only made a mental note to return later.
I also appreciate saving me the time of reviewing and trying to understand
the wrong material.

Now to test my understanding....

1. Lines of resolution as measured with the reference card is a way of
measuring the effective clarity or detail obtainable.

2. There would be no discernable difference in detail of a DVD as long as
the recording source supported 480 lines or greater.

3. If I am going to make an exact copy of a VHS tape to a DVD using the A/D
pass through conversion feature of my Sony camera, and I am only concerned
with playback as a DVD on a TV, I can capture this input in with an NTSC
compatible setting rather than DV-AVI which will create smaller files but
yield the same clarity in the resulting DVD.
Anonymous
September 3, 2004 10:08:48 PM

Archived from groups: rec.video,rec.video.desktop,rec.video.production (More info?)

To ask "what is the resolution" of a consumer camera is almost the wrong
question, as the differences are pretty small for most cameras in the same
price range.

I'd rather know the "f-rating" at 0db and 2000 lux. This gives a measure of
the camera's light sensitivity.

I'd rather know the S/N ratio. This is - - given the similarity of
resolution among a camera and its peers - - a better measure of picture
quality.

I'd rather know that I have manual control of when the gain kicks in. This
will allow you to keep the picture less noisy in marginal light situations.

I'd rather know that I had manual control of audio levels - - even if
they're buried in a menu.

But it will be like pulling teeth to get this info from the manufacturers.

Steve



"Jeffery S. Jones" <jeffsj@execpc.com> wrote in message
news:2c9hj0dgs71uk0faotkncq3c929ug5djbf@4ax.com...
> On Thu, 02 Sep 2004 20:33:19 GMT, "Bob Evans"
> <robert_evans_yah@yahoo.com._NOSPAM> wrote:
>
> >I was reading reviews of the Sony DCR-HC30 and DCR-HC40. It indicated
that
> >the 30 had 500 lines of resolution and the 40 up to 530. If these are
> >rendered to NTSC format which is 720x480, at what point woudl the extra
> >lines of resolution be visible and result in a better quality picture?
The
> >only time that comes to mind is while the editing/viewing on a computer.
If
> >it is intended to be burned to a DVD and viewed on televisions, would the
> >additional lines matter or improve clarity in anyway since they are
> >converted to 480 at that point anyway?
>
> First thing, "lines of resolution" isn't a measure of pixels. What
> it measures is the number of vertical lines visible within a square on
> the display (nowadays this is measured with electronic instruments,
> not visually). Since the TV picture isn't square, the total number of
> vertical lines which might be visible on the screen will be larger
> (roughly one-third larger) than the lines of resolution.
>
> Second thing, the frame size of a digital format extends outside the
> visible area on most TV monitors (some can show it out to the edge).
> For NTSC, that gives a maximum DV usable resolution of between 704 and
> 710 pixels. When you run through the numbers, that means that DV at
> 530 lines of resolution will need that 704 pixels to display it
> without loss, with a bit of rounding filling in the remainder.
>
> DVD resolution is only slightly smaller (704x480).
>
> The 480 dimension is fixed -- a poor TV or other video device might
> display them imprecisely, blurring the image a bit, but nothing can
> make NTSC TV show more than that (in standard definition anyway).
>
>
> Lines of resolution measures the apparent sharpness of the image,
> *not* its pixels of resolution. Some video devices offer sharper
> images than others, and if the recording medium can handle it, you'll
> actually see a difference. DV is already much higher resolution than
> SVHS or Hi8, let alone VHS, so 500 lines of resolution is quite good.
>
> An analogy might help: If you take a picture which is very out of
> focus, the image will be quite unsharp. You may not even see two
> clear lines on the screen. Yet the DV frame size of that blurry
> picture will be exactly the same -- 720x480 -- as one which is in
> perfect focus, showing excellent detail.
>
> Better camcorder technology can give you a little more detailed
> imagery from the DV format. 500 vs. 530 isn't a huge difference, but
> every little bit can help -- especially in poor light or other
> conditions where the image detail isn't easy to see.
>
> --
> *-__Jeffery Jones__________| *Starfire* |____________________-*
> ** Muskego WI Access Channel 14/25 <http://www.execpc.com/~jeffsj/mach7/&gt;
> *Starfire Design Studio* <http://www.starfiredesign.com/&gt;
Anonymous
September 4, 2004 12:48:24 AM

Archived from groups: rec.video,rec.video.desktop,rec.video.production (More info?)

"Tony Morgan" <tonymorgan@xtreme.pipex.net> wrote in message
news:X1c6ZnD+r7NBFwHW@zen54488.dircon.co.uk...
> In message <ch86pe$no1$1@plaza.suomi.net>, Jukka Aho <jukka.aho@iki.fi>
> writes
> >Bob Evans wrote:
> >
> >> I was reading reviews of the Sony DCR-HC30 and DCR-HC40. It
> >> indicated that the 30 had 500 lines of resolution and the
> >> 40 up to 530. If these are rendered to NTSC format which is
> >> 720x480, at what point woudl the extra lines of resolution
> >> be visible and result in a better quality picture? The only
> >> time that comes to mind is while the editing/viewing on a
> >> computer. If it is intended to be burned to a DVD and viewed
> >> on televisions, would the additional lines matter or improve
> >> clarity in anyway since they are converted to 480 at that
> >> point anyway?
> >
> >You are confusing "lines of resolution" (aka "tv lines") with
> >scanlines.
>
> He certainly is not.

You just put your foot in your mouth with that statement. Video equipment
specs for lines of resolution are not the same as scan lines. So the
statement "...since they are converted to 480..." clearly indicates he is
confusing lines of resolution with scan lines.
Anonymous
September 4, 2004 12:58:31 AM

Archived from groups: rec.video,rec.video.desktop,rec.video.production (More info?)

In message <Li2_c.22435$3l3.11121@attbi_s03>, Bob Evans
<robert_evans_yah@yahoo.com._NOSPAM> writes

Snipped....

>Now to test my understanding....
>
>1. Lines of resolution as measured with the reference card is a way of
>measuring the effective clarity or detail obtainable.

Yes - as viewed from the "end" medium.
>
>
>2. There would be no discernable difference in detail of a DVD as long
>as the recording source supported 480 lines or greater.

Yes.
>
>3. If I am going to make an exact copy of a VHS tape to a DVD using the
>A/D pass through conversion feature of my Sony camera, and I am only
>concerned with playback as a DVD on a TV, I can capture this input in
>with an NTSC compatible setting rather than DV-AVI which will create
>smaller files but yield the same clarity in the resulting DVD.

This is a little confusing (to me at least). On carefully re-reading it
a couple of time it is in essence correct - though not quite.

Your "...rather than DV-AVI" is not correct, since analogue pass-through
on your Sony camcorder can only convert the analogue (from VHS) to DV
(miniDV) which is captured as AVI DV on your computer. With your video
software (aka video editor) you will then "make" your AVI DV into an
MPEG-2, which is then used to create your DVD.

Because the "end" lines resolution depends on the lowest lines
resolution throughout the process, you will be unable to get much any
more than 240 lines resolution (which is what your VHS was at the start
of the process). To give it an overly simplistic analogy, if you have a
water supply that will provide a maximum of 1 gallon per hour, no matter
how far you open the tap at your washbasin, you'll never be able to get
more than 1 gallon per hour out.
--
Tony Morgan
http://www.camcord.info
Anonymous
September 4, 2004 12:58:32 AM

Archived from groups: rec.video,rec.video.desktop,rec.video.production (More info?)

Thanks Tony. The use of DV-AVI was copied from Windows Movie Maker. I'll be
sure to refer to as AVI DV in future posts. Funny you gave the pipe analogy.
That was very similar to the way I conceptualized the information from the
earlier posts. It also helps me confirm that I would be wasting my money
upgrading from the HC30 to the HC40 if my primary concern is picture clarity
of resulting DVD's which would be the minimum res in those two cases. I know
there is a lot more going on than that when determining picture quality, but
assuming all other things being equal I won't get better results if I do
everything the same with the more expensive camera in this line.
Anonymous
September 4, 2004 1:10:13 AM

Archived from groups: rec.video,rec.video.desktop,rec.video.production (More info?)

In message <Qq2_c.6458$w%6.4485@newsread1.news.pas.earthlink.net>, Steve
Guidry <steveguidrynospam@earthlink.net> writes
Snipped....

>But it will be like pulling teeth to get this info from the
>manufacturers.

Indeed. And the thing that really disturbs me is that no manufacturer
will specify just what quality of picture they're looking at when they
quote their "low light" lux figure. So you just cannot make meaningful
comparisons (from the specs) of how a camcorder (or digital camera for
that matter) performs in low light conditions.

--
Tony Morgan
http://www.camcord.info
Anonymous
September 4, 2004 1:18:08 AM

Archived from groups: rec.video,rec.video.desktop,rec.video.production (More info?)

"Tony Morgan" <tonymorgan@xtreme.pipex.net> wrote in message
news:tT5UAuFnzMOBFwru@zen54488.dircon.co.uk...
<snip>
>
> This is a little confusing (to me at least).

Everything is to you Mr Morgan, you're confused about non-loss formats,
non-lousy formats and now UK copyright lawn amongst others... :~(
Anonymous
September 4, 2004 1:51:07 AM

Archived from groups: rec.video,rec.video.desktop,rec.video.production (More info?)

Bob Evans wrote:

> I also appreciate saving me the time of reviewing and
> trying to understand the wrong material.

I can assure you the two links I originally gave (in the article
<http://google.com/groups?selm=ch86pe$no1$1@plaza.suomi.net>)
correctly explain the numbers you were asking about.

I can also give you several other references in similar vein:

<http://www.spectra-one.com/digitalvideo.html#tvlines&gt;
<http://jkor.com/peter/tvlines.html&gt;
<http://www.home-theater-faq.com/what_is_meant_by_lines_...;
<http://www.hometheaterforum.com/htforum/printpost.php?p...;
<http://www.hometheaterhifi.com/volume_6_3/essay-video-r...;

What I cannot give you is an explanation of Tony's post.

--
znark
Anonymous
September 4, 2004 2:09:55 AM

Archived from groups: rec.video,rec.video.desktop,rec.video.production (More info?)

Lines of resolution, as a term used within the broadcast industry, are
quite definitive and relate to the ability to differentiate lines on a
converging pattern from the sides towards the centre on a standard EBU
test card. The point is to count the individual lines resolved that have
not merged into a homogenous grey area.

With Standard Definition PAL video for example the limit is 540 lines
regardless of whether its a Digi Beta, D1 or DV device. The reason for
Sony only being willing to declare such cameras as the PD150/170 as
being "over 530 lines" is typically Sony cynical when the measure can be
quite specific. They don't want to confuse the market by admitting that
a PD170 achieves the same resolution as a ten time more expensive
DVW790. Picture quality however is defined by a lot more than just
resolution.

Analogue formats such as Betacam SP for example can read as many as 720
lines, not much different to Panasonic's ersatz version of High
Definition, but again quality is defined by a lot more than just
resolution.

Tape formulation has no effect on digital recording at all, since the
picture is defined by binary coded mathematics and compression ratios,
that's why long play mode on DV does not effect picture quality as with
analogue formats, what is effected is reliability and increased
vulnerability to glitches etc.
--
John Lubran
Anonymous
September 5, 2004 10:32:00 PM

Archived from groups: rec.video,rec.video.desktop,rec.video.production (More info?)

> You just put your foot in your mouth with that statement. Video equipment
> specs for lines of resolution are not the same as scan lines. So the
> statement "...since they are converted to 480..." clearly indicates he is
> confusing lines of resolution with scan lines.

I think you are right. But to an extent, if a device supports 480 scan
lines, wouldn't the lines of resolution supported for this device be that or
lower? In other words, if I only have 480 scan lines to depict an image
with, then I can't possibly show more than 480 rows in a single rendering,
right?

Anyway, if I understand the posts and the readings I have encountered over
the past two days, lines of resolution is a way of measuring the ability to
visually distinguish between lines in a pattern that converge. It would seem
to be a measure of effective clarity/detail whereas scan lines would not.
There are numerous elements through the process of recording with a camera,
storing to the media, capturing to a computer, converting formats, editing,
and storing back to DVD that could impact resolution. The process/artifact
involved in this activity that has the lowest effective lines of resolution
would seem to be the bottleneck defining what the maximum lines of
resolution observable when playing back the final product. Obviously it
could be less than this if there is a problem with the player or display
device, but it would seem to be the maximum.

Please let me know if I am viewing this incorrectly. I am trying to
understand enough about these concepts so that I can make an informed
decision regarding returning the camera I just purchase to obtain the next
model up in the Sony line of cameras which indicates it supports a greater
number of , etc.
Anonymous
September 6, 2004 2:20:06 AM

Archived from groups: rec.video,rec.video.desktop,rec.video.production (More info?)

Bob Evans wrote:

> But to an extent, if a device supports 480 scan lines,
> wouldn't the lines of resolution supported for this
> device be that or lower?

Neither: scan lines are horizontal, the lines measured for
"lines of resolution" figures are vertical.

Howver, by counting the highest number (densest pattern)
of _vertical_ lines you can distinguish when shooting a
test pattern, you get the maximum _horizontal_ resolution.
See <http://www.bealecorner.com/trv900/respat/&gt;.

"If a device supports 480 scan lines" does not even need
to be call into question: generally speaking, _all_ NTSC
camcorders are based on 480 active scanlines. The vertical
resolution is fixed to 480 scanlines for standard definition
(NTSC) tv; the horizontal resolution is not - and the "lines
of resolution" numbers refer to the horizontal resolution.

--
znark
Anonymous
September 8, 2004 7:04:25 PM

Archived from groups: rec.video,rec.video.desktop,rec.video.production (More info?)

Huge mistake on my part. Thanks for the correction.


"Jukka Aho" <jukka.aho@iki.fi> wrote in message
news:IFJ_c.2144$5m2.1872@reader1.news.jippii.net...
> Bob Evans wrote:
>
> > But to an extent, if a device supports 480 scan lines,
> > wouldn't the lines of resolution supported for this
> > device be that or lower?
>
> Neither: scan lines are horizontal, the lines measured for
> "lines of resolution" figures are vertical.
>
> Howver, by counting the highest number (densest pattern)
> of _vertical_ lines you can distinguish when shooting a
> test pattern, you get the maximum _horizontal_ resolution.
> See <http://www.bealecorner.com/trv900/respat/&gt;.
>
> "If a device supports 480 scan lines" does not even need
> to be call into question: generally speaking, _all_ NTSC
> camcorders are based on 480 active scanlines. The vertical
> resolution is fixed to 480 scanlines for standard definition
> (NTSC) tv; the horizontal resolution is not - and the "lines
> of resolution" numbers refer to the horizontal resolution.
>
> --
> znark
>
!