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Tom Wood
06-19-2003, 03:24 PM
Hi All,

I'll be creating a program entirely in Lightwave and editing in VT. From what I've determined, it's a good idea to keep an eye on things in production using a NTSC monitor. I read the setup article from the color bars thread, and it appears that having a monitor with the Blue Only feature is handy. Trouble is, all the Sony models with that feature are over $1,000. Can anyone recommend an inexpensive monitor with the blue only feature that is good for monitoring the NTSC signal during production in Lightwave and VT?

Thanks,

TW

John Huffman
06-19-2003, 05:06 PM
Hi Tom,

Go to http://www.ebay.com and type in "sony pvm 8" or "Sony pvm 13" in the search box. Look for Sony 802x series or Sony 134x series. The seller usually states whether blue gun is an option or you can tell by how many buttons are on the front panel. You can get an 8" for around $200 or a 13" for around $400. I also have one if you're interested.

John

Tom Wood
06-19-2003, 05:36 PM
Hi John,

You read my mind. I found this one:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3029967019&category=21517&rd=1

And Google turns up several other places with it for sale as low as $350:

http://www.vtrspecialists.com/usedvideo.htm

So I guess my next question would be, what other features are relevant to my needs? Are the number of TV lines important to me? It seems odd that this number would vary when the number of lines on a regular TV is fixed. What's up with that?

Thanks,

TW

John Huffman
06-23-2003, 09:05 AM
Hi Tom,

That's true about a standard analog TV. Their horizontal resolution is fixed at around 250 TV lines. However broadcast cameras and editing equipment can output up to 800 lines. Dv camera can output 400 lines. That is why they make 250, 400 and 800 line monitors. You would want to purchase the resolution according to your purpose and need. If you are editing or using one for a program or preview monitor higher is better. If you are just monitoring cameras for multi-camera switching lower is OK.

As far as other features: (uncommonly used) Multiple inputs, NTSC/PAL auto switch, 4:3 / 16:9 switchable, underscan, audio inputs, genlockable,

(commonly used) blue gun, loop throughs, AC/DC operation

Hope this helps...

John

vanguard
06-24-2003, 12:07 PM
Actually all tube based (picture that is...) NTSC televisions(and monitors) have 525 scan lines. Your DVCPro camera (and mine) that has a limiting resolution of 750 ish lines still pumps out 525 lines NTSC on composite (and component).

The stuff leaking out of the composite video cable in your hand : 525 lines.

Don't matter if'n its hooked to a 2" quadruplex, or a D-5 deck, its 525 lines.

"Lines" as a definition has grown to equate to bandwidth. So makers of fine production gear have reversed this to show relative betterness in the market.

One of my favorites is: "DVDs (video) can reproduce up to 450 lines of resolution.." Yeah right, perhaps on a still image of a multiburst chart at the highest bitrates.

People, your average hollyweird DVD lands somewhere between VHS and SVHS everytime.

But, back to monitors:

The limiting factor is the "grid" at the big end of the picture tube that focuses the three guns onto the phosphor.

It can reduce the number of lines by combining scan lines with less open grids.

BTW Trinitron monitors have not round holes in their grids, but wee rectangles...

Black and white monitors appear sharper than color ones because there is no grid.

LCD, plasma, and other display types usually (but not always) have less than the 525 broadcast standard.

This is why plasma displays in their current availability are cool to look at from a "gee it hangs on the wall perspective", but if you look critically, and do side-by-side comparisons, you see the picture quality when you look close (like around 10 feet away) pretty much sucketh.

Now they are improving....

One of our clients recently went from HD plasma displays in a tradeshow booth to direct-view CRTs, because they are waaay better from an image perspective...


For some fun ask the weiner at Best Buy or whatever to show you some direct view HD TVs.... He'll probably show you some rear projection junko, but if you hold out (like I did) the manager will be able to find it on the bottom shelf somewhere....

Weiner at my store was pretty darn impressed at how much better it looked...

Faroudja labs has made line doublers, and quadruplers, but need to be connected to special RGB projectors.

Oh please let the commish make the DTV standard 1080i!!!!!!

Whoops that opens a new can of worms...

Proof: If all analog tvs (and all CRT based NTSC displays are...) are fixed at "around 250 lines" then everything would look like VHS (which IS actually fixed at 230ish lines)... DVDs would look no better than VHS, Broadcast would look no better than VHS, and cable would look no better than VHS, no wait, its only marginally better than VHS anyways.

More important than lines IS bandwidth, which I'm sad to say is lacking in most reports on quality of signal from most manufacturers.

BTW the T2 actually has adjustable bandwidth!

.50 and a cup of Joe to the first person to correctly identify where this (nearly) secret slider is, and why you shouldn't fool with it!

JReble
06-24-2003, 02:25 PM
Ya. Mostly correct but you neglect to make the distinction between Scan Lines and TV lines of resolution. For the benefit of those having the above discussion regarding monitors....

There are in fact 525 "Scan Lines" in every NTSC signal since the format is established to include 525 horizontal scan lines per frame.

TV Lines of resolution (or horizontal resolution) which I believe they are speaking about on the other hand is the terminology used and abused by manufacturers of equipment to indicate video bandwidth capabilities. With higher horizontal resolution a piece of gear can reproduce or display the NTSC signal with its 525 scan lines in better clarity. The 525 scan lines of an NTSC signal equates to a vertical resolution of 525. Horizontal resolution measures the individual picture elements running along a screen from left to right.

The greater the number of vertical lines (or picture elements running from left to right along the screen), the greater the resolution. Higher resolutions result in images which are better defined and more fully whole. With low resolutions, the individual elements of the image become visible but with higher resolutions these elements tend to blend together to form a solid, cohesive image. This is why the phrase "lines of resolution" is so important even though the vertical resolution is effectively fixed at 525.

This is important while editing since you are better able to discern the ongoing quality of your NTSC signal before it is further distorted with lower bandwidth equipment down the line.

JReble
Fellow Engineer

http://www.ntsc-tv.com/images/tv/lum_bw.gif

Tom Wood
06-24-2003, 03:36 PM
This is all very helpful, thanks everyone.

But I still need to ask: How many lines of "TV lines of resolution" should I be considering when buying a broadcast monitor for -my- needs, which is to monitor the image as it is created in Lightwave and eventually processed out through VT onto DVD or DVCAM tape? It appears that 250 is typical on the smaller screens, with 400, 600 and 800 costling progressively more on the larger screens.

Thanks,

TW

JReble
06-24-2003, 04:00 PM
I'd go for at least 600 lines of horizontal resolution.

vanguard
06-24-2003, 07:27 PM
Ya know you're right.

The scan lines vs. TV lines is what is correct there...

So please excuse my micro-rant there.

I'll be more awake before I get all fired up next time....

JReble
07-09-2003, 09:10 AM
Also as an F.Y.I. :

I was pouring through some old articles and found that you can create a functional blue only pattern on monitors that do not support it by placing a blue gel over the screen. SMPTE recommends the Kodak Wratten 47b. The equivalent from Rosco is the #385 Royal Blue.

Tom Wood
07-09-2003, 11:02 AM
I ended up getting this one:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3032874406&category=21517&rd=1

It should be here tomorrow, looks like a good deal if it works.

TW

vip3dran
07-10-2003, 11:37 AM
Tom,

I have that EXACT monitor as my primary video monitor!

Take my word . . . you will love it!!
(if it works, that is)

Tom Wood
07-10-2003, 01:09 PM
Thanks vip3dran,

I'm going to connect it to a regular VCR to test it. I assume that if it turns on and shows a decent image, then that would be considered 'working'.

How do you have yours hooked up? I don't have the breakout box so I only have the one set of BNC connections out of the VT card. But I also have a S-Video out on my graphics card, the NVidia 380 XGL. I thought I'd use that connection to monitor things while in Lightwave. The Sony DSR-11 DVCAM tape recorder only has composite and S-Video in, no component. I got an adapter that converts the two BNC connections for luminance and chrominance to S-Video, so I'd use that for recording.

Or, it looks like I could plug the S-video adapter into the Sony monitor and run a S-Video cable from the monitor to the DSR-11, assuming there is no signal degradation on the loop-thru. Boys and their toys....

TW

JReble
07-10-2003, 02:17 PM
You should be able to run your video through your monitor with satisfactory results. That's what I was going to recommend. You can feed your y/c video from the Toaster into the monitor and take the loop through from the monitor on to the VTR. Just make sure to use good quality s-video cables for the connections.

Then you can take the composite out of your DSR-11 and feed that into the other input on the monitor and feed the Y/C out of the deck right into your Toaster card direct. That keeps your video in and out of the editor high quality while letting you monitor your deck alone as well via composite.

ned
07-10-2003, 02:52 PM
But even with NTSC 525 lines aren't there only 480 or 486 (in the US) lines on screen because of vertical and horizontal blanking taking out some of the 525 in the signal?

JReble
07-10-2003, 09:20 PM
Essentially correct. The entire NTSC video image is 525 lines. NLEs generally assume that the active video portion is 486 minus the vertical blanking interval which is not visible on consumer televisions which are overscanned by design. Most NLEs only work with the active video portion and then the hardware generates the full NTSC signal on output. This is why most computer based editors are not capable of retaining the extra interval data like closed captioning. This portion of the incoming signal is stripped on input since it is not part of the active video portion.

DonN
07-23-2003, 08:43 PM
You can make any monitor have a blue only button if you look at it thru a piece of Wrattan #42 blue filter gel (plastic) which is fairly dark blue. I have several of these mounted on 35MM slide frames, cardboard, collected over the years.
The only use is for looking at NTSC color bars and adjusting, the hue, sat and brightness controls to calibrate the monitor.
Ive never bought the stuff, but should be in photographers supply stores.
I put the same bars up on my computer rgb monitor, look at ToasterVision, and adjust it to match the video monitor.
Works out great.
Don