After the test cards, what?

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After the test cards, what?

Postby Viewmaster » Fri Apr 06, 2007 6:36 pm

I have just joined this forum, becoming interested in NBTV and have looked at all the great apparatus built by members and shown on the Loughboro' archives of photos on the NBTVA web site. Also many other sites on the web.

As I have already mentioned on the forum of, The British Heritage Television Project, my concern is that after looking at test cards etc what next?

I would like to be able to transfer, say, Laurel and Hardy films to NBTV.
The problem here is that if one uses, say, a 625/32 line converter, this is a 'catch all' image system, whereas NBTV requires big close ups of just part of the whole image.

So, I wonder if any NBTVA member has investigated ways of projecting 8/super8/16mm film and using a NBTV camera to go in close to capture the essential big close ups?
Are there lack of lighting problems I wonder?

My first thoughts were that one could either directly adjust the film projector speed right down to sync with NBTV or use, say, the film sprocket holes to trigger a single frame take on a slightly modified NBTV camera (to o/p a single NBTV frame on being triggered).

This could then be then recorded into a PC, the blank film 'pull down' time being removed later? This seems a relatively simple way without getting involved in yet more equipment.

In both these cases big close ups of Laurel and Hardy could be obtained onto the NBTV camera.......or Arnold Schwarzenegger if that is your preference ! :)
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Postby Andrew Davie » Sat Apr 07, 2007 12:39 am

How about using Video2NBTV from http://users.tpg.com.au/users/gmillard/nbtv.htm ?

I haven't used this yet, but this seems the way to go, to me. DOwnload any number of clips online, convert via the above, and you have NBTV content to your heart's desire.
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Framing NBTV Content.

Postby Stephen » Sat Apr 07, 2007 1:07 am

It seems to me that the problem with any converter, including Gary's software, would be the lack of means to "pan" the source material to capture desired content within the 2:3 aspect ratio of the NBTV frame. I would think that the best way to approach this would be with a computer programme that converts video content to display on a PC display screen at a 12.5 Hz rate. The actual display refresh rate would be high enough, say 75 Hz, so that the phosphor persistence of the PC display screen would provide a uniformly lit image. An NBTV camera, synchronised to the 12.5 Hz frame rate of the display, could then pan the displayed image on the PC display screen to capture the desired content.

I have no expertise in such computer programming, but it seems to me that such a programme is feasible and would be a worthwhile project for someone skilled in the art.
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Postby Viewmaster » Sat Apr 07, 2007 1:50 am

As I pointed out, and as Stephen said, a straight conversion of any kind is a 'catch all' system and not suitable for converting many medium/long shots which we find in filmed material.
Big close ups are required, not simple conversion.

Well, I've just stripped down a 35mm. projector to get at its condenser optics so maybe I will start building a NBTV camera and try find a way of getting close ups off filmed material without having to wait for some clever PC software to be developed.

I would have thought that those with a NBTV camera have already tried to do this straight off a film cinema screen at home. I wonder what the results were like?

For me, at any rate, it would be more of an adventure and romantic to use a NBTV camera, rather than let a PC to do the job.....
...just imagine staggering around in front of a big cinema screen with a NBTV camera in order to get close ups ! :)
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Postby Andrew Davie » Sat Apr 07, 2007 2:27 am

I just don't see this as an NBTV issue. The same problem happens when displaying (say) a 16:9 movie on a 4:3 screen. You either letterbox, or you pan&scan. There's obviously software to do this already, and I bet it is written generically. I'd run the film/video through this first, giving a pan&scan version, then run that version through the standard NBTV conversion (which will crop) and that would be good enough.
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Postby DrZarkov » Sat Apr 07, 2007 3:39 am

32 Lines are very good for portraits, but for "real" TV it is not enough. In the late 20th/early 30th in Germany they used a system similar to Baird's (in fact, the "Fernseh AG" and Baird were working together) an the germans decided to use 30 lines in horizontal 3:4, which is more looking like a cinema picture. The "Telehor" (a Nipkow-TV made in Germany) could be used in two ways: vertical scanning for portrait (Baird system) or horizontal "postcard" viewing (Berlin system). I think the easiest way if you want to watch converted movies or TV-porgrammes would be to make a "german" machnical TV, which would be a very simple change of a club-standard monitor. But is it worth it? Not without reason the british Baird system was much more successful than the german mechanical system.
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Postby gary » Sat Apr 07, 2007 11:21 am

I don't see any reason why it would be any easier to obtain close-ups with a camera rather than through software, so the only real reason for doing the this way would be for the adventure and romance you mention. Under some circumstances the resolution doing it this way could be higher than by doing it through software but this would only happen at high magnification where the area of interest of the original material has a lower resolution (after digital capture) than the 32 x 48 of the final result.

Video2NBTV makes the assumption that the area of interest is always in the centre of the screen, or at least within a centered rectangle of 3:2 proportion. It uses the aspect ratio of the original material to determine the overall rescaling and which axis is to be cropped (if necessary).

It would be relatively straight forward to allow these parameters to be modified by the user thereby providing pan and zoom. In addition it would be easy to allow the frame rate of processing to be altered allowing 'slo-mo' during panning and zooming, however, as Andrew has pointed out there is, almost certainly, generic software to allow this to be done as a form of pre-processing to the original material, so it is debatable as to whether it is worthwhile adding to the Video2NBTV application itself, however if there was enough interest in doing this I might be arm twisted...
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Postby Viewmaster » Sat Apr 07, 2007 5:59 pm

gary wrote:Video2NBTV makes the assumption that the area of interest is always in the centre of the screen, or at least within a centered rectangle of 3:2 proportion. It uses the aspect ratio of the original material to determine the overall rescaling and which axis is to be cropped (if necessary).

It would be relatively straight forward to allow these parameters to be modified by the user thereby providing pan and zoom. In addition it would be easy to allow the frame rate of processing to be altered allowing 'slo-mo' during panning and zooming, however, as Andrew has pointed out there is, almost certainly, generic software to allow this to be done as a form of pre-processing to the original material, so it is debatable as to whether it is worthwhile adding to the Video2NBTV application itself, however if there was enough interest in doing this I might be arm twisted...


As a newbie to NBTV could you tell me what Video2NBTV is please?
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Postby Andrew Davie » Sat Apr 07, 2007 6:05 pm

Viewmaster wrote:As a newbie to NBTV could you tell me what Video2NBTV is please?
Albert.


Video2NBTV is software written by Gary Millard. The blurb states...

"Video2NBTV is a programme which takes a video file (avi, mpg, mov, wmv, in fact just about anything that can be played by Windows Media Player) and outputs in NBTV *COLOUR* format (Robers/Brown colour format 32 line missing sync pulse vertical scan line format only). Note this format is Black & White Compatible, that is, the output will play back on B&W viewers/monitors. The audio track associated with the video file is extracted and placed in the right hand audio channel."

It can be downloaded for free at http://users.tpg.com.au/users/gmillard/nbtv.htm

PS: I might add that "programme" is a Television-type show, whereas "program" is a computer-type bit of software. In this case, the incorrect use is kind of ironic :)
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RE After The Testcard

Postby Phil Hunter » Sat Apr 07, 2007 8:32 pm

As a new member myself I have used a very crude transfer method via Gary Millard's conversion program.
I have simply ran a DVD on my laptop whilst filming it via a video camra,
I have just tried to pan manualy to get a 32 line close up on any particular scene.
Given that I have not attempted any form of sync it works far better than expected - if anyone can help me with an alternative I would be very
grateful !
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Postby gary » Sun Apr 08, 2007 12:40 am

Andrew Davie wrote:
Viewmaster wrote:As a newbie to NBTV could you tell me what Video2NBTV is please?
Albert.


Video2NBTV is software written by Gary Millard. The blurb states...

"Video2NBTV is a programme which takes a video file (avi, mpg, mov, wmv, in fact just about anything that can be played by Windows Media Player) and outputs in NBTV *COLOUR* format (Robers/Brown colour format 32 line missing sync pulse vertical scan line format only). Note this format is Black & White Compatible, that is, the output will play back on B&W viewers/monitors. The audio track associated with the video file is extracted and placed in the right hand audio channel."

It can be downloaded for free at http://users.tpg.com.au/users/gmillard/nbtv.htm

PS: I might add that "programme" is a Television-type show, whereas "program" is a computer-type bit of software. In this case, the incorrect use is kind of ironic :)


Hmmm, I don't allow that "programme" is incorrect in this context:

http://simple.wiktionary.org/wiki/programme

although I do admit that "program" has fallen into common usage, and even The Concise English Dictionary appears to have "rolled over":

http://www.askoxford.com/concise_oed/programme?view=uk

although I do find that a bit ambiguous.

I'm sure that the use of the spelling "program" reflects the locality within which it's use in relation to computer software first became popular rather than indicating that it has a specifically different meaning. In which case it is fair to use the spelling "programme" in a locality that prefers that form.
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Postby Viewmaster » Sun Apr 08, 2007 12:54 am

gary wrote:Video2NBTV makes the assumption that the area of interest is always in the centre of the screen, or at least within a centered rectangle of 3:2 proportion. It uses the aspect ratio of the original material to determine the overall rescaling and which axis is to be cropped (if necessary).

It would be relatively straight forward to allow these parameters to be modified by the user thereby providing pan and zoom. In addition it would be easy to allow the frame rate of processing to be altered allowing 'slo-mo' during panning and zooming, however, as Andrew has pointed out there is, almost certainly, generic software to allow this to be done as a form of pre-processing to the original material, so it is debatable as to whether it is worthwhile adding to the Video2NBTV application itself, however if there was enough interest in doing this I might be arm twisted...


As a newcomer here I don't wish to twist any arms, but looking at this clever application wouldn't it be nice if, as it was transfering to NBTV one could drag, using the PC mouse, a NBTV window outline about the picture selecting just those parts to be converted. In this way one could not only pan about but even crane up the scene......
......by twisting both arms one could zoom in/out at the same time too. :)
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Postby DrZarkov » Sun Apr 08, 2007 5:08 pm

Maybe that would be possible using another software first? With any graphic-software you could do that, you can define in Photoshop for example a mask with the aspect ratio of 3:2 and move it by hand over the picture. It would not be too difficult 1. to convert a movie to a lot f single frames (at the Macintosh I would use Graphic Converter for the whole thing, fo the PC I think Irfan View in connection with Photoshop would be a good choice), cut the frames (you could easily write a plugin, which takes automatically takes all the single frames one after the other), and save it after that as a movie again. Where are the Photoshop-experts here?
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Postby Viewmaster » Sun Apr 08, 2007 6:23 pm

I make animated films so are used to dealing in single frames etc, (using Adobe Premier and Stop Motion Pro).
But breaking a film down and selecting and manipulating frames to be re assembled is very time consuming.

One really needs to take close ups, pan and zoom on the hoof in real time, whilst the original is playing.
That is why I first mentioned using a NBTV camera in front of a cinema screen at the start of this thread.

Anyway I have decided, (well nearly!), to build a combined camera/monitor even tho' I have to position 48 holes instead of the 32.....
...I do have mechanical experience....and a NBTV beginners optimism! :)

A very nice example of such a machine is shown here (13th photo down)...
http://www.nbtv.wyenet.co.uk/conv04.htm
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Postby Phil Hunter » Tue Apr 10, 2007 11:45 am

Viewmaster wrote:I make animated films so are used to dealing in single frames etc, (using Adobe Premier and Stop Motion Pro).
But breaking a film down and selecting and manipulating frames to be re assembled is very time consuming.

One really needs to take close ups, pan and zoom on the hoof in real time, whilst the original is playing.
That is why I first mentioned using a NBTV camera in front of a cinema screen at the start of this thread.

Anyway I have decided, (well nearly!), to build a combined camera/monitor even tho' I have to position 48 holes instead of the 32.....
...I do have mechanical experience....and a NBTV beginners optimism! :)

A very nice example of such a machine is shown here (13th photo down)...
http://www.nbtv.wyenet.co.uk/conv04.htm
Albert.


I have come to the same conclusion also.
I have hidden behinnd making a commercial telervisor fit a "nice" case so my next objective is to make a scanner.
Good luck and keep us all posted.
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