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Nick Beecham
23-10-2000, 8:00 AM
Please can some kind person answer the following and sorry for being a bit ignorant:

1)Which gives the better results: NTSC viewed with progressive scan or PAL without.
If the former, and I bought the Pioneer 737 (assuming I had a compatible projector) would there ever be a reason to buy Region 2 again?

2) What is a scaler? Is it the same thing?
(I suspect not, sorry to be thick)

Many thanks in advance
Nick

23-10-2000, 8:51 AM
Firstly, sorry, I can't really answer the first part, and sadly HCC didn't test the pro-scan output of this player. However, I suspect that pro-scan NTSC would better PAL - just an opinion though.

Never buy PAL R2 again? Well there are some discs available here not available on NTSC R2 & R1, but of course a chipped 737 will play both. (The 737 is based on the 'NTSC only' Pioneer DV-37 Elite model)

A video scaler performs a similar function to line doublers, tripplers and quadrouplers, however, it has the flexibility to tailor the output to the resolution of a particular display.

For example, if a LCD based device has say 800 pixels in the vertical, one could set the scaler output to 800. Also with front projector CRT's, too few scan lines could leave gaps between these lines if the 'dot size' is very fine, too many scan lines and they could overlap if the 'dot size' is too large, leading to a smeary soft look.

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HT Dude
23-10-2000, 9:32 AM
Originally posted by Nick Beecham:
Please can some kind person answer the following and sorry for being a bit ignorant:

1)Which gives the better results: NTSC viewed with progressive scan or PAL without.
If the former, and I bought the Pioneer 737 (assuming I had a compatible projector) would there ever be a reason to buy Region 2 again?

NTSC Progressive is better than PAL interlaced. You'd only want to buy region 2 if the region 2 version of a movie were better for whatever region. Or the DVD was simply not available elsewhere.

2) What is a scaler? Is it the same thing?
(I suspect not, sorry to be thick)

Many thanks in advance
Nick

A scaler scales the image to a different resolution. For example, the PC Software DVD players like Win DVD or Power DVD scale the image to whatever resolution (or window size) you want. They do a good job of it, too.

Nick Beecham
23-10-2000, 12:05 PM
Many thanks Guys

The reviews in HCC of the latest line doubled Barco projector also stated that a scaler was required to avoid the soft effect. I'm also considering the latest LCD Sony projector which is line doubled.

Does this mean that, for best results, only a PC based system will do? Can't you get stand alone DVD players with a built in or add-on scaler?

All the best
Nick

Gordon @ Convergent AV
23-10-2000, 2:50 PM
The Barco actually has a doubler built in not a scaler (although it will benefit from using one) and the SonyLCD has a scaler not a doubler.

In fact, virtually every Fixed panel projector has a scaler built in. These take the incoming video and re-size it to fit the native resolution of the panel in the device.

There are companies who will modify DVD players and fit video scaling boards inside them (cinematrix) spring to mind.

If you just watch DVD's then such a device or a HTPC(home theater pc) could be the answer. If youwatch lots of sources on a video projector then an off board video processor will improve the picture of every source you send through it.

All the best,

Gordon

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Nick Beecham
23-10-2000, 3:01 PM
Many thanks for all your help, everyone.

Nick

Lance
28-10-2000, 2:00 PM
I also have some beginners questions I would be grateful if you could help me out with.
I have seen you can get scalers/doublers that produce outputs that vary from 480p to 1080i and 1200p.
I would like to know how you can tell whether a projector can be scaled, if at all, and to what level.
Presumably the higher the amount of scaling the beter the picture?
Does the size of the lenses in the projector affect this?

Thanks very much

Lance

Oasis
29-10-2000, 8:50 AM
Lance,

You can scale to virtually any projector but it depends on the type as to what you should do.

If the projector is pixelated (LCD, DMD/DLP, D-ILA) then you should scale to the native resolution of that projector. i.e if the unit is 1024x768 then you should set that resolution on the scaler. If you cannot set exactly the right resolution on the scaler to suit the projector then you will end up with two stages of scaling (in the scaler and then in the projector)this is why a simple doubler/quadrupler is not usually worthwhile for these types of unit

If the projector is not pixelated (CRT or ILA)then you scale to the resolution that just causes the scan lines to meet, but not overlap. This is not the maximum resolution quoted, far from it in fact. as a guide -
6" CRT - 800x600 max
7" CRT - 800x600
8" CRT - 1024x768
9" CRT - 1152x864
There are variations depending on whether there is electromagnetic or magnetic focusing and whether there is astigmatism controls and the like, but these are rough guides. A scaler would normally be connected to the projector as if it were a PC source and to check whether a scaler would work with a projector, have a look at the spec sheet, it should be capable of easily exceeding the rate you intend to apply. As a VERY rough guide (I haven't sat down and done real calculations)
800x600 - 32Khz
1024x768 - 40Khz range
1152x864 - 50Khz range
1280x1024 - 60Khz range
the actual numbers depend on frame rate (50/60/72/75 Hz etc) but could be estimated far more acuratley by taking the number of active lines (the resoutions above are given as pixels x lines)adding 17% to allow for blanking and fly back lines and mulitplying by the frame rate in Hz, remember 1000Hz = 1KHz.

Hope this helps!
Oasis

Lance
02-11-2000, 3:46 PM
Thanks very much Oasis, for you reply, I think I understand it!
So If you have a 7" projector that has maximum resolution of 800x600, it would be ok to scale at 720p, as the maximum would be 800?
Thanks again

Lance

Oasis
02-11-2000, 8:10 PM
Lance,

Sorry, I guess I wasn't quite specific enough, sorry!

If we take 800x600 SVGA computer resolution. That means 800 pixels across the screen and 600 lines down the screen.

720P means 720 lines down the screen. this is more than the 600 of 800x600. The P bit means Progressive Scan (it would be I if it were interlaced like normal TV)
The number of lines when we are talking about PC resolution or HDTV resolutions is the number of active lines (i.e. ones that actually have picture information in them)
so;
PC Res = HDTV = Also known as!
640x480 = 480P = line doubled NTSC
576P = line doubled PAL
800x600 = 600P = SVGA PC
720P = HDTV format
1024x768= 768P = XGA PC
etc...

Hope this helps.
Oasis

[This message has been edited by Oasis (edited 02-11-2000).]

Lance
05-11-2000, 9:20 PM
Thanks Oasis,
I now understand!
Regards
Lance