Mailing List archive
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[linux-dvb] Re: Help with J2 RGB
In an email sent to me rather than the list you mentioned the
following. I hope you don't mind me forwarding this part to the list as
I wanted further opinions.
On 29/04/2004, at 10:19 PM, Emil Naepflein wrote:
You have to terminate the RGBS lines with 75 Ohm to ground and don't
connect anything to the regular outputs. I once experimented with RGB
output with a RGB to S-video converter. This converter has switchable
termination for each input signal. Without termination the picture was
horrible as you have seen, with termination switched on the picture was
fine, but not better than the picture on the direct S-Video output.
In the meantime I dropped the RGB output all together because you
cannot
expect much better quality without considerable effort to clean/filter
the high-frequency RGB signal. The PC environment is just to noisy. I
am
happy with the S-video signal into a Lumagen scaler which feeds an XGA
DLP beamer with with an anamorphic ISCO lens with VGA. Depending on the
quality of the transmission the image is breathtaking on a 243 cm wide
16:9 screen.
Emil
So I'd just like to know whether I have indeed been chasing an
impossible dream with the RGB output of J2. Is it true that in practice
the RGB will not give a visibly better picture than the S-Video? I
certainly know that on my STB and DVD players the RGB gives a
significantly better picture than S-Video. Is this impossible due to
the noise in the PC?
If it is impossible then why have so many on the list claimed that this
is the best way to go?
Furthermore is it significant that I am connecting the 75 Ohm resistors
to the J2 ground at the SCART end? Should I be connecting to the SCART
ground? Indeed is SCART from the TV delivering ground on pin 21? How
about all the other ground signals on the SCART? Would it be better to
connect the resistors to the SCART ground coming from the TV? Or would
it be better to connect them to the J2 ground at the J2 end?
But wait, there more! What about shielding? How can I effectively
shield the connectors at the SCART end? It's all essentially out in the
open INSIDE the PC case. I could take photos to help explain what I
mean.
I have secondary reason for wanting to use RGB though and that is so
that I can use the pass through on my STB and DVD player to have
everything going through one AV input and therefore one channel on the
TV (for usability purposes associated with my parents). I have already
tested that with good SCART cables there is no visible reduction in
image quality. In order for this to work though all devices must be set
to RGB output as the AV input on the TV is manually set to RGB and
displays a black screen if the signal it gets is not RGB.
Regards,
Michal
--
Info:
To unsubscribe send a mail to ecartis@linuxtv.org with "unsubscribe linux-dvb" as subject.
Home |
Main Index |
Thread Index