[vdr] Re: Deinterlacing

["Reinhard Walter Buchner" <rw.buchner@freenet.de>]

Hi Guido,

> What exactly is the screendoor effect (sorry for my ignorance)
> - maybe a german term?

No its a common term. Think of looking at a movie through a fly
screen (the stuff in front of your windows).

> Brightness and contrast is good, at least i'am satisfied (1200 ANSI,500:1)
if
> the sun is not directly shining into the room - all the white walls...

Don't try to compare digital lumens vs CRT lumens. They are
NOT measured the same. Hence the difference. A contrast
ratio of 500:1 is pretty low ;o)) A CRT will have a MUCH
higher (factor 15-20 at least) contrast ratio. It DOES require
a dark room, tho. But cinemas don't have flood lights on
during the movie either ;o))

> The only thing is the noise it makes (36dB) -

That is indeed another reason. As are lamp prices. I didn't
want to mention those to prevent a CRT vs. digital war ;o))

> But i wonder why they can have such extremely high contrast ratios
> (beside  that the room has to be really dark to make use of them).

Well, that's quite easy to understand. A CRT which is set to dark
emits *NO* light. An LCD even at full voltage will never be able
to block out all the light. That's the reason why LCDs can't faithfully
reproduce black images. They are a washed out grey. To increase
contrast, digital folks use grey screens. While this improves blacks
a little bit, it also reduces the reproduction faith at the top of the
IRE scale. Whites are no longer a true white.

> Well - and i assume the price is the most  important factor - not
everybody
> has the money to screw something the price of a decent car to the ceiling
and
> hopefully have a good insurance!

Well, I didn't pay anywhere near 50K Euro for my CRT ;o)) I paid 2250
Euro for it. It has under 3000 hrs on it and the tubes are in pristine
condition (tube lifetime when not run under industrial conditions is
somewhere around 15K hours) So, I'll have to watch a few more
DVD before I reach that limit ;o)) BTW: mine frame floor mounted,
so it can't fall down  ;o))

> My PJ autodetects the output of the DVB-S as 680x554 (viewing PAL
> material) so  the resolution is already interpolated once and a view
> pixels cut away...

A CRT doesn't do that ;o)) It puts out what you throw at it (within
sensible limits). If you are viewing a film that has 704 x 576, then
your PJ is cropping the picture.

As Emil pointed out, it is a matter of personal taste and how picky
you are and what your living conditions are like (space, etc)..

Greets,
Reinhard