Talk:S-VHS

Separated video?
Is it just me or does S-video standfor SEPARATED video ? mean Y/C on tape and thus, better quality


 * No, S-VHS stands for "SuperVHS." An S-VHS recording is no more separated than VHS; both use color-under recording, with the chroma subcarrier shifted to a low frequency and the luma signal recorded via FM on a higher-frequency carrier.  SuperVHS achieves greater luma bandwidth simply by using a higher carrier frequency and wider deviation in the FM. S-Video, on the other hand, refers to a signal, connector, and cable that carries the luma and chroma on separate conductors -- hence "separate video."  Jeh 23:08, 29 March 2006 (UTC)


 * The answer to the top question is YES! The question was asking about S-video connetors, not S-VHS.  Indeed the S here stands for Separated video, the luma and chroma are separated on this type of connector.  Some idiots think that the connector is a SVHS connector which it isn't, even some Panasonic SVHS recorder manuals are at pains to point this out. Colin99 20:46, 22 April 2006 (UTC)


 * IF the question had been about the S-video connector, then you would be correct. However I think the OP was asking about the tape format, even though he says "S-video", because of his wording "....mean Y/C ON TAPE...".  It seems very clear to me that the question is addressing the tape format and not the connector.  JVC contributed to this confusion by creating a logo, a graphic rendition of "S-VHS", which they used on tape and tape equipment.  Jeh 22:19, 17 February 2007 (UTC)

Well, back when the ONLY product that used an "S-Video" jack was an S-VHS VCR, it )in the JVC S-VHS decks manuals) referred (as well as many products around the late 80's/early 90's) to the jack as a S-VHS jack, not S-video. S-video came into play once S-VHS failed to gain popularity and DVD, videogames and other devices started using the S-VHS jack since it was the best until component.

I hate revisionist history... —Preceding unsigned comment added by 162.115.236.120 (talk) 20:07, 22 May 2009 (UTC)


 * A somewhat ironic statement. The first use of the S-video connector was in JVC's debut S-VHS machines, but it appeared on Sony Hi8 equipment within two years, and was never a proprietary JVC-only item. It was always intended as a industry-standard connector for separated video. That JVC (and some others) erroneously labeled chose it as "S-VHS" on some products - even after it was being used for Hi8 and other uses - does not change that. Nick Cooper (talk) 09:33, 19 July 2016 (UTC)

PAL information needed
No mention of PAL, only NTSC specific. Could somebody with more knowledge please expand this article? Peter S. 18:51, 5 April 2006 (UTC)

Is S-VHS demonstrably superior to VHS in a domestic environment?
We have something approaching a contradiction. Top paragraph says: "when timeshifting TV programs on S-VHS equipment, the improvement over VHS is not noticeable" The bottom paragraph says: "Nevertheless, viewing an S-VHS recording through a VCR's built-in RF modulator yields a discernable perceived quality improvement over VHS"

They're not quite saying the same thing, the first is talking about timeshifting and the latter about an RF hookup (which is presumably used for timeshifting, what else?). The truth is of course that it is subjective. Some people can see the difference between VHS and SVHS, some can't. It's influenced by the tape, recording source, monitor and make/model/condition of machine. I've seen one set of VHS recordings (only one mind you!) which was so clear, noiseless, and carefully made as to subjectively surpass many recordings made by low-end S-VHS decks. Often however VHS is a fuzzy noisy mess and S-VHS is a less noisy fuzzy mess.

Without making it all too wordy, we should modify these phrases to ensure that both tend to point to a superior performance of S-VHS over VHS which may or may not be immediately obvious depending upon various factors. Volunteers to clean this up? Colin99 15:50, 2 January 2007 (UTC)


 * I made a first change, very easily, by changing the first bit to say the improvement IS noticeable. It certainly is to me.  Jeh 22:18, 17 February 2007 (UTC)


 * If you record a foreign movie or TV show that has subtitles, the difference between VHS and Super VHS is immediately obvious. In VHS the subtitles take-on a blurry appearance and are difficult to read, whereas the Super VHS preserves them perfectly.  - 00:06, 13 April 2009 (UTC)

S-VHS, S-VHS ET, SQPB
Could someone with knowledge in this area expand the explanations of S-VHS ET and SQPB, paying particular attention to where S-VHS recordings on S-VHS medium is viewable (only S-VHS decks?) and where S-VHS ET recordings on "normal" VHS medium is viewable (is it viewable on standard VHS decks or only those that support a special "S-VHS ET" format?). What does SQPB stand for and what is it (medium, technology, recording format, etc)? Also the sentence "As a sidenote, most S-VHS VCRs can also make VHS recordings on S-VHS tape, and conversely, conventional VHS VCRs can record on S-VHS videotape" is a bit wordy and confusing as to its exact meaning. —The preceding unsigned comment was added by 68.153.109.3 (talk) 20:07, 13 April 2007 (UTC).


 * I've seen in a few places that most VHS VCRs made since 1995 can play S-VHS recordings made on S-VHS tapes, though the output is only VHS quality. I've also read that the "ET" S-VHS recordings 'may not' play on VHS VCRs.


 * VHS has 3 megahertz luminance bandwidth while S-VHS has 5.25 megahertz bandwidth. Old VHS decks will read the greater than 3 megahertz recording, but won't know how to handle it, so they display "garbage" on the screen.   VHS decks with Super-Quasi-PlayBack will use low-pass filters to remove anything above 3 megahertz, thereby cleaning up the image.   Theaveng (talk) 11:31, 21 November 2008 (UTC)

Combo decks
JVC, Matsushita(Panasonic), and at least one other company made combo decks that had both an S-VHS transport and a MiniDV transport. Many of them also included a Firewire port for connection to a computer. What I've never been able to find out is whether or not they provided computer control of the the S-VHS transport or direct digitizing from it, or if to digitize from VHS one had to first copy to a MiniDV tape. —Preceding unsigned comment added by 208.100.251.47 (talk) 10:48, 5 September 2007 (UTC)

from S-VHS, via Y-C, to S-Video.
SVHS is the follow-up of the video recording VHS, a video-recording standard, the old competitor of BETAMAX(SONY) and of VIDEO2000(PHILIPS). I am a PHILIPS man and in those days the competitors trick was to use a new way of transferring the video from the recorder to the TV. Instead of offering the usual composite signal of both Colour and Video Base band Signals: CVBS, where both signals: Colour and Black and White were mixed together, they send both signals separated to the TV. This excluded the necessity of using a signal-separation filter in the TV, thereby decreasing cross-interferences between both signals and.. improving Bandwidth and off course...... improving the definition of picture details! Because of that, PHILIPS and SONY just called the same idea: Y/C-signal-transfer. Y for video black/white and C for Color. I think the S originally stood for 'super', but the word 'separate' is actually better, because of the nature of the video-connection. So SVHS is correctly replaced by S-Video, forgetting the recording history. —Preceding unsigned comment added by 77.248.104.2 (talk) 20:40, 9 April 2009 (UTC)


 * S-video predates Super VHS by about ten years. In fact by the time S-VHS arrived, studios were already using component video as part of the Betacam format.  - 00:08, 13 April 2009 (UTC)

"Needs citations" template
Editor Hinata removed the "needs citations" parameter from the "multiple issues" template, saying that the article does "site[sic] references". And has now done so twice.

WP policy requires that inline citations (and it's Citations, by the way, not Sitations) be present for "any material challenged or likely to be challenged, and for all quotations" (see WP:CITE, WP:V), and that citations are strongly recommended for everything else: "All material in Wikipedia articles must be attributable to a reliable published source to show that it is not original research".

The policy does also state that "in practice not everything need actually be attributed", but that does not mean that two inline citations are sufficient for an article of about 20 paragraphs. Ideally it means a citation for every statement or claim of fact.

And by the way... the two citations that are present here do not even directly apply to the article topic! One is used to justify a statement regarding poor chroma resolution of other video tape formats, and the other for the resolution of HDV!

Sorry but the notion that this article has enough references or inline citations is completely unsustainable. I did change the parameter from "unreferenced" ("it does not cite any references or sources") to "citations missing" ("It is missing citations or footnotes"), as that is a better fit. Jeh (talk) 23:17, 21 September 2010 (UTC)


 * Backed up, Jeh. I was going to add a "citation needed" tag on the "Modifying VHS Cassettes for S-VHS recordings" section, when I noticed that the need for citations was global to the article. Twipley (talk) 17:53, 22 September 2010 (UTC)
 * In this "modifying VHS Cassettes" section, I would have liked to add that i have about 100 modified VHS tapes recorded on a JVC S-VHS deck in 2002, that are still readable with a panasonic NV-HS1000 as I'm writing this in December 2014. However, this is "original research" and shouldn't probably be included in the article. Is the information about the weak coercivity leading to very fast deterioration sourced anywhere? Shouldn't it be deleted then? — Preceding unsigned comment added by 2A02:2788:A4:1480:85D1:987D:5A00:6C02 (talk) 19:06, 11 December 2014 (UTC)
 * I'll come back to the article with refs over the weekend. Plenty of RS available on the subject itself. As for the homegrown mods, it's better be reduced to just one line: "Yes, it was possible, no, it didn't work". Get real, it's all in the past, who really cares? It's like spending hours describing overclocking on a 286 (WTF is a 286, mommy ...). East of Borschov 09:29, 23 September 2010 (UTC)
 * Even though there is a global citation tag, specific tags are still a good idea as they serve to highlight which particular parts of the article are being challenged. 86.183.24.235 (talk) 16:44, 6 March 2011 (UTC)

confusing
this article is confusing. what are "-lines" that it keeps referring to? IWannaPeterPumpkinEaterPeterParker (talk) 21:09, 15 January 2012 (UTC)

Answer To Confusing/Explanation of Comparison's To Other Formats
These are extremely subjective, because the Kell Factor and EIA chart are very subjective results, as they rely solely on what different human eyes perceive, as well as how the different equipment is manufactured and processes the information. There is no scientific evidence that S-VHS is 400 lines, because it might appear that way to someone in their sixties, but for a twenty-year old they could, quite possible and depending on their equipment be able to make out up to 950 lines. What is scientifically known are the frequencies that the video is recorded at. S-VHS for instance records and plays back it's luminance between 5.4 and 7.0 MHz, depending on record speed and type of tape used, while its chroma is always recorded at 629kHz, but is up converted to the NTSC and PAL standards on playback. Compare this to Super Betamax that records between 4.4 and 5.6MHz with chroma stored at 688 kHz. Thus the comparisons on all the pages related to video recording should not be here, because they provide information that is not scientific and are very subjective conclusions that are misleading.24.156.246.33 (talk) 15:40, 19 August 2013 (UTC)


 * I have copied this over to talk:Betamax and answered there. Trying not to fragment the discussion... Jeh (talk) 10:21, 29 August 2013 (UTC)

Is S-VHS Can Be Recorded In The VHS VCR In Standard VHS Quality
Is S-VHS Can Be Recorded In The VHS VCR In Standard VHS Quality — Preceding unsigned comment added by 186.93.24.96 (talk) 00:07, 19 July 2016 (UTC)
 * Your question is a little unclear, so I'll cover all the bases:
 * * A standard VHS VCR will record standard VHS on an S-VHS cassette
 * * An S-VHS VCR will record standard VHS on a standard VHS cassette
 * * An S-VHS VCR can record standard VHS on an S-VHS cassette if S-VHS recording is switched off
 * * Some S-VHS VCRs can record S-VHS on a standard VHS cassette, but results vary depending on the quality of cassette used
 * * Some standard VHS machines can play back S-VHS recordings as slightly better than standard VHS quality
 * Nick Cooper (talk) 08:52, 19 July 2016 (UTC)

I Owned A Samsung VCR But It Can Record S-VHS Tapes?
I Owned A Samsung VCR But It Can Record S-VHS Tapes? — Preceding unsigned comment added by 186.93.24.96 (talk) 01:59, 20 July 2016 (UTC)

S-VHS quality
S-VHS had around 400 tv scanlines of resolution, while NTSC had 480 active and 525 total scan lines. 330 scan lines for NTSC is wrong.Rockclaw1030 (talk) 14:35, 25 May 2018 (UTC)


 * I'm sorry, but you are making a fundamental (but very common) error. The word "lines" is being used here in two different ways. You need to understand when we are talking about "lines of horizontal resolution per picture height" vs "horizontal scan lines". They are not the same thing, are not limited by the same factors, and do not have the same specs in NTSC.


 * The phrase "scanlines of resolution" is indicative of your confusion. That is not a phrase that should ever occur. It's a little like saying "volts of power" or "amperes of energy". We just don't measure that property with that unit. It isn't even wrong.


 * Yes, "330 scan lines for NTSC is wrong", but the article is not saying that. It's saying that NTSC broadcast has about 330 lines of horizontal resolution per picture height. And that's correct. Even though there are about 480 visible scan lines.


 * "NTSC had 480 active and 525 total scan lines" is correct but we're not talking about scan lines here. The article never claimed that any NTSC format had "330 scan lines". Please note that both NTSC VHS and NTSC S-VHS VCRs, as well as NTSC laserdisc, likewise record and play back video with 525 total scan lines and about 480 active. If they didn't they couldn't play on older NTSC TVs! The sweep circuits in such TVs simply could not create a raster with a much different scan line count than that. In other words, the vertical resolution of all of these machines is identical, and identical to that of NTSC broadcast, as long as they are all NTSC. These recording or broadcast formats all have the same number of scan lines. Nevertheless their horizontal resolution varies greatly. Horizontal resolution is not determined by the number of horizontal scan lines!


 * The number of scan lines limits vertical resolution. (Not to 480, though!)


 * The 330 figure is the horizontal resolution. In other words, how many different-brightness details could you resolve in the horizontal dimension? It is unrelated to the number of scan lines (except by design decision, which I'm not going to get into here). It derives from the bandwidth of the luminance signal and by the observable period of the horizontal scan line. This is about 51 microseconds in all NTSC media. (Assuming the pre-color 15750 Hz horizontal line rate, 15750 scan lines/sec = about 63.5 microseconds per scan line. Only 51 usec of that is visible, the rest taken up by the horizontal sync pulse, etc.) In broadcast NTSC, the luma bandwidth is limited by the presence of the sound subcarrier to about 4.3 MHz. A 4.3 MHz signal has time for about 220 cycles (which would show as alternating light and dark spots) in 51 usec. Which is 220 line pairs (as the photographers would express it), or in video terms, 440 lines ("details") resolvable across the scan line.


 * It is expressed in "lines of resolution" because it is measured with a test pattern consisting of lines. Vertical lines. Or an array of converging nearly-vertical lines, with numbers along side the array to show the "lines of resolution" at each density, as you see on older test patterns. In broadcast NTSC, these "fuzz out", become indistinct, at about 440 (not 480!) lines counted across the width of the picture. Since it was deemed more useful to express this figure of merit over a width of the picture equivalent to the picture height, and NTSC uses a 4:3 aspect ratio, this figure is multiplied by 3/4 to get "330 lines of horizontal resolution per picture height".


 * It's 240 for VHS, and about 400 for S-VHS and Laserdisc, because these formats provide different luminance bandwidth than NTSC broadcast. Jeh (talk) 18:40, 25 May 2018 (UTC)


 * See also the article television lines, which is what we're talking about in horizontal resolution. That article is linked from the text you keep deleting. And this article from Broadcast Engineering, an industry magazine confirms my analysis above and also shows why the effective vertical resolution is about 330 lines per picture height, even though there are about 480 visible scan lines. Jeh (talk) 21:49, 25 May 2018 (UTC)


 * Dear JEH, I apologize for my mistake. I looked it up, and yes, NTSC has around 339 TV lines and 480 scan lines. TV lines are different from scan lines. I did make that mistake. I ask for you forgiveness. I was wrong. Though, I have not found any any reference to S-VHS being at 400 TV lines. If you have some source, I would love to see it. Also, the source used in the article, "Comparison Of VCR Formats - Sencore tech tips" (PDF). Sencore. AV-iQ.com - NewBay Media, LLC. Retrieved 20 May 2016., is iffy, as when I click on it, it is not a secure or safe link. I think that another safe source should replace it. ThanksRockclaw1030 (talk) 23:33, 25 May 2018 (UTC)


 * Admittedly the "lines" terminology is confusing. You are far, far from the first to fall into this trap!
 * For the reference for S-VHS's resolution, you could start with google "S-VHS" "400 lines".
 * The "unsafe" warning from your browser just means that it's an http link, not https. So there is no certificate that associates sencore.com with Sencore, the company. (Well, there may be, but Sencore isn't using it.) But Sencore has been in the professional test equipment business for decades; I think we can trust them to not knowingly host malware! Emphasis on "knowingly" - an https link provides no guarantee that someone within Sencore didn't put malware on their site, or that bad guys on the outside have not found a way to hack the site to add malware to it. https only says that the web site is authenticated as being controlled by whoever owns the sencore.com domain and that the protocol between you and the site is encrypted by either TLS or SSL. Jeh (talk) 00:22, 26 May 2018 (UTC)


 * Good to know Sencore is a reputable place. Thanks for the reference!Rockclaw1030 (talk) 00:54, 26 May 2018 (UTC)

MAGMA
OK, one big confusion is that most often, but not always, lines means line pairs, especially in the analog case (horizontal in TV signals). In the discrete (raster) case, lines often means lines. For video signals, there are many ways to lose bandwidth, filtering being a favorite. In the case of video tape, with an FM luminance channel, it is even worse. The bandwidth of an FM signal is a complicated function of the bandwidth of the modulation, in theory going to infinity. FM is needed for luminance, which goes down close to 0Hz (close enough) and up to some MHz. The limitations of lower quality tape are hard to quantify. There is the capture effect for FM demodulation (though that page does a poor job of explaining it). One result of the capture effect is that the S/N after demodulation is much higher than before. Gah4 (talk) 23:32, 25 May 2018 (UTC)


 * In photography, "lines" indeed means "line pairs". But in video, "330 lines of horizontal resolution" means that you can visually resolve a test pattern with 165 pairs of alternating white and black details across a width equal to the picture height. It could be measured with a single scan line with alternating white and black dots, but it's far easier to see if you stretch that vertically... forming vertical lines. That's why we measure horizontal resolution with a test pattern consisting of vertical (or nearly so) lines, and vice versa. Anyway, in video we count both the white and the black lines in that pattern in the count of "lines".  Jeh (talk) 00:29, 26 May 2018 (UTC)


 * But video is photography. But OK, for digital images, including video, it is commonly in pixels on both axes. And with scanned raster, it is scan lines because there isn't much other way to do it.  I said most often because sometimes it isn't, and as video gets more digital, pixel counts will become more common. Looking at line pair, photography, video, and display resolution didn't help much. Do you have a reference for analog video being in lines that are not line pairs?  Gah4 (talk) 00:49, 26 May 2018 (UTC)


 * Yes. The RS-170 standard and everything that followed it. I have a copy. Do you?
 * The Image resolution article isn't much better... but anyway... regardless of whether "video is photography", common practice in photography is to quote resolution in "line pairs", while in analog video, horizontal resolution has always been expressed in "television lines" that are counted as I described above. This has nothing to do with video getting "more digital". It's been that way since before NTSC. One white + one black line on the test pattern counts as two lines. The bandwidth calculations I went through in the preceding section will confirm this. If it were quoted in "line pairs" then we would be saying that NTSC broadcast was at just 165 or 170 line pairs of hor. res. pph.
 * The vertical res, by the way, if by that you mean "the number of resolvable details," is not the same as the number of scan lines, but only about 70% of that due to Kell factor. Jeh (talk) 01:15, 26 May 2018 (UTC)


 * OK, but Kell factor says up to 0.9 for modern source and display devices. I have wondered for some time about the filtering done in resolution reduction for video. I know the math, and it isn't so hard in 1D, but way more computation than current devices could do in 2D. But it should also be higher for digital sources, such as character mode video displays, which naturally follow the scan lines, and aren't sampled analog signals. Gah4 (talk) 08:12, 26 May 2018 (UTC)


 * "modern source and display devices" doesn't apply to analog-sourced television, which means any time you have a camera (even a digital one) pointed at the real world - or at a frame of film for that matter. Don't take my word for it! Get an NTSC video test DVD and look at the resolution test patterns. And once Kell factor has happened at your source, because your picture details can't be relied on to fall exactly on your scan lines, it doesn't matter how "modern" everything downstream is. Jeh (talk) 10:23, 26 May 2018 (UTC)


 * Also, I find it hard to ascribe this to the storage S-VHS recorders and tape will store and play back whatever vertical resolution the source has. This is not true for horizontal resolution, which will be limited by amplifiers and other filters along the way, and finally the tape itself. Gah4 (talk) 08:29, 26 May 2018 (UTC)
 * "S-VHS recorders and tape will store and play back whatever vertical resolution the source has." Absolutely not true. An NTSC VCR is designed for 262.5 scan lines per field and 60 fields (well, 59.94 in color) per second. Each field exactly occupies one "track" recorded by the head on one side of the head drum. Each track is written diagonally, starting near one edge of the tape and nearly reaching the other. The start and end of each field must match the start and end of the track. Now, you think you can change the vertical resolution. That means changing the number of scan lines per field, yes? Ok... if you do that but don't change the line rate, then you've changed the field rate. (They are mathematically linked; line rate = field rate x lines per field.) Your VCR flatly won't work if you change it by much, because it is designed for a very narrow range of field rates (drum rotation rate) and it just won't follow Vsync if it's much different from expected. If on the other hand you change both the number of lines per field and the line rate, so as to keep the field rate the same, then the VCR won't know what do to with the different line rate. (If it somehow managed to keep working, your older CRT couldn't follow it anyway, so why would the VCR have been designed to cope?) A VCR is not a general-purpose recorder of analog signals! It is made specifically to record NTSC or PAL video and there are many design decisions and compromises in it that are built around the specs of those standards. Jeh (talk) 10:15, 26 May 2018 (UTC)


 * OK, that isn't what I meant. You have the 262.5 lines, minus sync pulse time, and those lines all have to be displayed. A VCR can't, for example, average out, that is, vertically low-pass filter, between lines. A display device, for example CRT with a defocused beam, will reduce resolution, essentially as a low-pass filter. If I generate a source with alternate black/white lines, easy to do digitally, and record it, the VCR can't reduce it. In theory it is possible with analog delay lines and such, or with digital filters, but even digital systems don't do that. Any Kell factor filtering is done before the signal gets to the VCR, and not by the VCR itself, or after in the display device. I suppose in theory, one could build a multi sync (in computer terms) VCR, that would adjust the drum speed and such to match. And I believe that there are multi-system NTSC/PAL/SECAM VCRs that can do that for those frequencies. I have seen explanations of the effect of playing PAL/SECAM tapes on NTSC VCRs, and I suspect some can figure it out and some can't. But the meaning of the statement was that the VCR can't change the vertical resolution within the fixed line rate. I haven't thought about this before, but I presume they put the same optical low-pass filter on video cameras as on still cameras, if the optical system has higher resolution than the CCD. Gah4 (talk) 16:04, 26 May 2018 (UTC)


 * I don't specifically have RS-170, no. As you note, for photography, and I now assume you mean film photography, and I suspect optics too, it is commonly in line pairs, but commonly specified as lines, the pairs being implied. As far as I know, the implied pairs goes back to the beginnings of actual study of photographic systems. It is, at least, in all the Kodak data sheets that I read. Is there a place to download actual RS-170?  Gah4 (talk) 02:20, 26 May 2018 (UTC)


 * You are correct about line pairs. And photographers' resolution test charts are "calibrated" the same way. Even when you use them with a digital camera, we may still speak of "lines" but we mean "line pairs", because that's what the legend on a photographer's resolution test card means. This is likely why the term "television lines" originated, to avoid that ambiguity.
 * The RS-170 spec should not be a free download anywhere, as it is copyrighted material. Jeh (talk) 05:00, 26 May 2018 (UTC)


 * Just being copyrighted doesn't mean there aren't free versions. The ethernet standards are copyright IEEE, but they have free downloads for non-commercial use. Also, ECMA standards are free, and often similar to others. Gah4 (talk) 08:12, 26 May 2018 (UTC)


 * (Must you argue with every little point, however non-germane?) True, but I have never seen a legitimate free download of an EIA spec. IEEE and ECMA are different organizations and have their own policies. The copy of RS-170 (actually EIA-170) I have is revision TR-135, dated November 1957. I bought it maybe 20 years ago. (EIA-170A incorporates the color standards defined by the NTSC.) It says "reproduced by GLOBAL ENGINEERING DOCUMENTS with the permission of EIA under royalty agreement." Selling copies of their standards is one way that standards orgs earn money to continue operations. Of course I wouldn't be surprised if there are non-legit versions that are out there.
 * (Short version of above: "It's copyrighted material and the IP owner is enforcing that." Better?)
 * But US copyright law does permit copying of short excerpts for reference purposes, so...
 * 2.5.5 Resolving Power
 * DefinitionThe resolving power [...] is expressed in terms of a number of lines resolved on a test chart. For a number of lines N (normally alternate black and white lines) the width of each line is 1/N times the picture height.
 * There you go. Both the white and black lines are counted. Again, this is consistent with the derivation from the bandwidth that I gave in the previous section, and that in turn is confirmed by the ref I gave to Broadcast Engineering magazine. Jeh (talk) 09:27, 26 May 2018 (UTC)


 * Thanks. I sometimes post in photography forums, and the problem of line counting comes up there pretty often, especially in the compare digital to film sense.  It is especially interesting, as film has a long tail on its MTF curve, so you have to choose some point on the curve. But also, digital cameras usually have an optical low-pass filter, or optical system of limited resolution, so you can't directly compare to pixel count. Gah4 (talk) 15:46, 26 May 2018 (UTC)

depiction of military use in popular culture
Some day someone with too much time on their hands may want to substantiate the references to S-VHS tape in

1) Blue Thunder when Lymangood learns of the tape storage in the Blue Thunder helicopter and knows of a similar system from his time on an aircraft carrier. 2) Red Storm Rising by Tom Clancy where it is used in a recording system mounted on F-14 Tomcats who are surreptitiously trailing a flight of bombers to see where they are headed. Both of which refer to or call back to uses by the U.S. Navy. ...and place them in a Popular References section. This assumes it's worth the effort which I am not at all sure that it is. — Preceding unsigned comment added by 50.34.131.98 (talk) 23:37, 4 April 2020 (UTC)

0.4MHz, and I-Q coding
The article often mentions the 0.4MHz limit of the chroma signal, and how much worse that is than broadcast. With I-Q modulation, and not well described in NTSC, I has 1.2MHz and Q has 0.5MHz limit. But NTSC was designed to make it easy to decode along the blue and red axes, with only 0.5MHz resolution, and just about all TVs made do that. (There are a few exceptions.) So, 0.5MHz is more than 0.4MHz, but not a lot more, and I suspect one would have to look pretty carefully to see the difference. NTSC did the actual studies to find which color differences people can see with more resolution, and came up with the I-Q axes to match. As well as I know, neither PAL nor SECAM followed that. Gah4 (talk) 22:22, 16 February 2022 (UTC)

PAL ED-Beta?
In the section discussing S-VHS vs. ED-Beta, there is this sentence: "In PAL markets, depth multiplexed audio was used for both formats." Did PAL ED-Beta exist? 86.142.94.246 (talk) 09:06, 17 September 2023 (UTC)