VHS resolution???

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Can i burn a Video cd with the vhs res.?

-- SaSy Superior (bufeo@hotmail.com), December 15, 1999

Answers

No. VCD resolution must be 352x240 for NTSC and 352x288 for PAL.

-- Josh (josho@hotmail.com), December 15, 1999.

I have often wondered about the term "resolution".

What if the original is a full frame 720 x 576 or 720 x 480 resized to 352 x 288 or 352 x 240 in the process of making the vcd.

In PAL a full frame 720 wide is expanded to the full width of 768 and the vcd goes from 352 to the same 768.

Tests support that there is a loss as a result of that and the full frame version wins and VHS quality is not achieved from the VCD.

If on the other hand, you compare two images from the same size source, for example, if both are expanded from 352 to 768 wide then there is little difference and the VCD will win and in that case VHS+ quality is achieved.

Put another way, anyone working from full size frames (720 wide) is always going to see VHS- quality from the VCD and if working from approximate half size frames (352 wide), is going to see VHS+ quality as the end result.

In NTSC the analogue TV screen of 4:3 format is only 640 wide, so the 640 wide image from a dv camera is expanded to 720 in the camera at the take and is reduced to 640 wide when processed for viewing on the TV, the reverse of the PAL system.

If your scanning photos for use on a VCD then this process needs to be taken into account so that circles are viewed as circles and not elipses on the TV.

Thats why there is a different pixel ratio quoted in the specs for each of the TV systems NTSC & PAL, in round figures PAL 0.916 and NTSC 1.12 or there abouts.

-- Ross McL (rmclennan@esc.net.au), December 20, 1999.


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