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50 Hz VS 100 hZ


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#1 Bobstar

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Posted 19 January 2004 - 11:33 PM

I have a Sony 50 Hz set and occasionally I notice flicker.

I understand that 100 Hz sets remove flicker. Does this also apply to digital TV transmissions or only to analogue?

Read that 100 Hz sets can have vibrations in horizontal lines and that this is resolved by a digital scan set? Is this correct?

What are the pros / cons of 100 Hz sets as compared to 50 Hz sets? I know that some people don't like 100 Hz sets.

#2 surroundfan

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Posted 20 January 2004 - 02:47 AM

The big problem with 100Hz sets vis-a-vis 50Hz sets is the introduction of digital motion artefacts if the 100Hz processing is implemented poorly. To my eyes, they can also reduce the sharpness of the picture.

See whether you can find a set where you can disable 100Hz processing and compare them back to back.

#3 shannon c

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Posted 20 January 2004 - 01:08 PM

For comparison purposes David Jones (Sydney, City) have an LG 76cm 50hz running alongside the 100hz model.

#4 delbz

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Posted 20 January 2004 - 02:05 PM

My Panasonic TX-51P100H has a vertical split-screen feature in the menu that displays both 50 and 100Hz on the TV. The flicker in the 50Hz part of the screen is very noticeable when compared in this way.

#5 countryslicker

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Posted 20 January 2004 - 03:36 PM

Definitely try and see a side by side test.

When I went down to Encel to buy my STB ten days ago, I was able to see a side by side test watching a high definition Ch 9 live telecast. The standard definition 100 Hz Loewe CRT TV (one of which I own) was noticeably superior (somewhat sharper, no flicker) to that of a high definition widescreen Loewe 50 Hz TV (at 3 times the price). Doesn't really make sense to me - I'm no expert - but the comparison was a real eye opener.

#6 surroundfan

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Posted 20 January 2004 - 07:10 PM

What were the two Loewe models used to compare the picture?

#7 robertr

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Posted 20 January 2004 - 07:40 PM

A HD Loewe Television - Interesting, to my knowledge HD displays manufactured in Germany do not exist.

#8 countryslicker

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Posted 20 January 2004 - 08:11 PM

Impossible to remember what I saw...in a large store like that there were about 50 TV's playing, lots of customers waiting to be served, and (I suspect) a lot of smoke and mirrors being used by the salesman oiling their way around the floor.

I have always been under the impression that all Loewe TV's are 100 Hz anyway. Luckily I already have one, and only needed a STB.

I'm no expert - I was only reporting on a side by side demo during which the the salesman led me and the other customers through a demo of what I stated in my post. He did give me a brochure in which he has circled the Xelos 5381 ZW.

In general, I think that down the track there's going to be a lot of customers being sold the wrong equipment by misinformed salespeople. Locally here, a salesman at one of the larger stores tried to convince me that by buying a HD STB I would be able to watch HD programs on my existing Loewe TV. True, except not in HD. I'm lucky I didn't fall for that - maybe others won't be.

#9 mrtv

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Posted 21 January 2004 - 03:39 AM

countryslicker, on Jan 21 2004, 02:11 PM, said:

Impossible to remember what I saw...in a large store like that there were about 50 TV's playing, lots of customers waiting to be served, and (I suspect) a lot of smoke and mirrors being used by the salesman oiling their way around the floor.

I have always been under the impression that all Loewe TV's are 100 Hz anyway. Luckily I already have one, and only needed a STB.

I'm no expert - I was only reporting on a side by side demo during which the the salesman led me and the other customers through a demo of what I stated in my post. He did give me a brochure in which he has circled the Xelos 5381 ZW.

In general, I think that down the track there's going to be a lot of customers being sold the wrong equipment by misinformed salespeople. Locally here, a salesman at one of the larger stores tried to convince me that by buying a HD STB I would be able to watch HD programs on my existing Loewe TV. True, except not in HD. I'm lucky I didn't fall for that - maybe others won't be.
Hi there,

You say that salesmen are miss informed, I think not it's more like I'll sell you that product and by the time you find out bad luck...

Also I don't think Loewe make HDTVs.


Regards,


Mrtv

#10 Darklord

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Posted 21 January 2004 - 03:06 PM

mrtv, on Jan 21 2004, 09:39 PM, said:

Also I don't think Loewe make HDTVs.
Loewe definitely don’t make any TVs with HD input out of the box. However Encel are now marketing the optional VGA card as an "HD input" as it supports 480p and 576p input (technically HD in Australia).

The catch is there are only two set top boxes that will output a 576p picture via VGA that is suitable for use with the VGA card. The Thompson and Panasonic HD boxes. And even then there are issues given the VGA card is not designed to work with STBs.

Considering its VGA input only (no progressive component input), there are associated display problems with the VGA input, and the card only supports 576p, I think its very unfair, and 'borderline misleading' (even though it is legal) to market the VGA card as an ‘HD option’. Now all Encel do is put the card in any Loewe TV with the Q2500 chassis, feed it a 576p signal and call it an "HDTV". No wonder many of their superior quality 100Hz TVs look better when displaying the Nine demo loop. Down-converting 1080i to 576p@50hz actually looks worse than down-converting 1080i to 576i@100hz unless you use advanced ‘per pixel motion adaptive de-interlacing such as that from Faroudja (certainly not available in any STBs in Australia)

More about this topic here.

#11 mrtv

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Posted 21 January 2004 - 04:16 PM

Darklord, on Jan 22 2004, 09:06 AM, said:

mrtv, on Jan 21 2004, 09:39 PM, said:

Also I don't think Loewe make HDTVs.
Loewe definitely don’t make any TVs with HD input out of the box. However Encel are now marketing the optional VGA card as an "HD input" as it supports 480p and 576p input (technically HD in Australia).

The catch is there are only two set top boxes that will output a 576p picture via VGA that is suitable for use with the VGA card. The Thompson and Panasonic HD boxes. And even then there are issues given the VGA card is not designed to work with STBs.

Considering its VGA input only (no progressive component input), there are associated display problems with the VGA input, and the card only supports 576p, I think its very unfair, and 'borderline misleading' (even though it is legal) to market the VGA card as an ‘HD option’. Now all Encel do is put the card in any Loewe TV with the Q2500 chassis, feed it a 576p signal and call it an "HDTV". No wonder many of their superior quality 100Hz TVs look better when displaying the Nine demo loop. Down-converting 1080i to 576p@50hz actually looks worse than down-converting 1080i to 576i@100hz unless you use advanced ‘per pixel motion adaptive de-interlacing such as that from Faroudja (certainly not available in any STBs in Australia)

More about this topic here.
Hi there Darklord,

I have just one question, Are the Loewe tubes capable of 576p. Because I thought that they can only do 576i.

But I agree with you about 576p wouldn't be HD. I personally think it has to be 1080i.

Regards,

Mrtv.

#12 Darklord

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Posted 21 January 2004 - 04:25 PM

mrtv, on Jan 22 2004, 10:16 AM, said:

I have just one question, Are the Loewe tubes capable of 576p?
Yes. They support up to 1024x576p. Admittedly they do look very good when fed a native progressive signal (such as that from Channel 7), or a properly de-interlaced film on DVD (from an HTPC) but down-converted 1080i from an STB looks fairly average.

#13 Adrianr

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Posted 21 January 2004 - 04:50 PM

I bought a cheap 100Hz 76cm Teac Widescreen (<$1500) and are extremely happy with the picture, after tweaking some settings including the noise filter (which if mine has it, then pretty much any 100Hz must)

Ultimately I really find the quality of the picture LIVES AND DIES by the quality of the source.

I.E.:

- Put a poor quality DVD, D-STB or god-fordbid Analog PAL source up and it will look *average* - worse than putting it on a 50Hz screen. All the noise and poor resolution of the image gets totally shown up by the digital resampling of a 100Hz TV.

However,

- Put a good quality picture - any *good* DVD (even something like Kath and Kim - filmed digitally) or the best SD stuff (Ch.7 HD, 9 or 10 studio stuff, latest TV shows) - and the picture quality blows away 50Hz.

You not only get no flicker, but even more importantly I love NO MORE SCANLINES !! The 100Hz and Digital processing really clean up and sharpen the image. Also it's suprising how many DVD's can look near-perfect on 50Hz CRT's but really get shown up on my 100Hz (Their problem not mine).


So yes I'm extremely happy overall with my screen and can't stand looking at 50Hz TV's anymore!! And it's about the cheapest 100Hz you can get

Adrian

P.S. Darklord your dead right regarding Ch.7 HD on a 576 screen. It's native resolution so its about the sharpest source for a 576 screen - 50 or 100Hz - p or i.