Quote:
Originally Posted by user58
i dont know much about vhs i not even know if the 50 frames are full pictures
if i assume they are lines and not full pictures that raise new questions
some information say they are frames called "even field/odd field" are they lines are they full frames ? are the 50 or 60 lines or fullframes ?
the pictures i took dont look different from the example i repostet
progressiv made the best quality (interlacing looked very smooth but lower resolution and lagging)
progressiv had the line artefacts
it looks like the colorcomb.jpg example from above
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They're probably 25i with rasters so you get even and odd fields; by bob-deinterlacing them with, let's say, QTGMC, you get 50fps progressive and that's the way it should be. Leaving aside the whole phosphors story of CRT TVs, modern TVs are all progressive and whenever they get an interlaced signal, they bob-deinterlace it on the fly, so you should bob it.
Interlace was made because CRT TVs displaying rasters were based on a beam hitting the screen and making raters brighten up (you can think about rasters as ancient pixels). The problem was that the beam could hit only a few rasters at a time, so doing it progressively would have led to flickering as when the last raster (bottom right) was lit, the first raster (top left) was already fading, so they split the screen in 50 lines, 25 even and 25 odd that were refreshed every time, so you could think at the Even lines displaying the current frame and the odd lines displaying the immediately successive frame. In Europe it was 50 times per second 'cause it was easier to make it work at the same rate as the monophasic current reaching user homes and in the U.S it was 60 times per second for the very same reason. Nowadays, interlaced doesn't make sense as TVs have been able to display pixels for years and, you know, all the pixels bright up at the very same time all together, so there's no need for interlacing and every display is progressive, therefore you should bob-deinterlace it to 50p using both Even and Odd fields to make a progressive frame, otherwise your TV will do it for you.