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Discussion Starter · #1 ·
Ok folks, the tweak-bug bit me again!


I have a Sony G70 fed by a HTPC outputting 720p / 60Hz. I have been very happy with it and have not done anything to it for more than a year.


However I am curious if this can do 1080p.

How many of you G70 owners out there use 1080p on your PJ on a daily basis?


Here is my reason of looking at 1080p:


When I display a 1080p version of (blu-ray) HD DVE's SMPTE RP 133 Resolution Chart on my setup I cannot read the percentage readouts around the squares in the center of the screen. For reference, look at this image:

http://upload.wikimedia.org/wikipedi...PTE_RP-133.png


Anyway, out of curiosity I changed the output of my HTPC to 1080p/60Hz and roughly corrected the geometry (I did not converge but I shut off R and B tubes)


I was surprised to see that now I was able to read the (above mentioned) numbers in that pattern (with only the green gun on.actually with only the red gun on.it is even more clear..forget about only blue it sucks (expected?))



Of course there are no scan-lines visible at 1080p. However I can still easily make out the 1-line on and 1-line off pattern easily (what is it called?) .in both horizontal and vertical planes. Does it mean this PJ is actually resolving 1080p just fine?


I would love to hear your opinion on this.


My setup:
  • Sony G70 PJ
  • Newer HTPC with nVidia 8600GTS card
  • Power DVD8, PDVD 7 and TMT for BD playback.
 

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The G70 can't fully resolve 1080p @60hz the image is soft compared to running A custom res, Then A LOW HOUR G70 is capable of displaying A stunning image....


The best results can be achieved with A Moome HDMI/Gamma card and A high end stand Alone VP

such as A DVDO VP50pro or similar that can run custom resolutions and has HDMI 1.3 or HDSDI, A Blu-Ray player set to output 1080 24p YcBcR 4:2:2.

and the VP setup to output A custom res of 1920x817 @48hz YcBcR 4:2:2 to A correctly calibrated low hour G70 + Moome HDMI/Gamma combo...

This will get you pretty much the best picture A G70 can produce the end result will Yield A super sharp picture compared to inputing 1080p @ 60hz from A Blu-Ray....


Cheers...
 

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Discussion Starter · #3 ·
Hmmm..... How about doing the same thing with a HTPC?


IMHO a HTPC>CRT can also do what your chain of "BD player > VP50 > Moome > CRT" can do.


Full gamma correction is there along with color correction.

My HTPC allows custom resolutions at custom refresh rates.


I have never tried 1920x817. I believe that will be 2.35:1 right?


But what about images which are 16:9...like I watch a lot of HD TV content in 720p native (FOX). That will have to be displayed in either 1280x720p @ 60Hz......which is displayed fine anyway.


But there are plenty of Blu-ray movies with are in 16:9 format. How do you display that on 1920x817 ?



As for 48Hz refresh....... Are you sure you are displaying that refresh rate on the G70?


When I tried 1920x1080p @ 48Hz yesterday, the PJ did sync up but the image was flickering a lot.....definitely not watchable.


I will try out 1920x817 @ 48Hz tonight.


Thanks!


Quote:
Originally Posted by cinema mad /forum/post/15412955


The G70 can't fully resolve 1080p @60hz the image is soft compared to running A custom res, Then A LOW HOUR G70 is capable of displaying A stunning image....


The best results can be achieved with A Moome HDMI/Gamma card and A high end stand Alone VP

such as A DVDO VP50pro or similar that can run custom resolutions and has HDMI 1.3 or HDSDI, A Blu-Ray player set to output 1080 24p YcBcR 4:2:2.

and the VP setup to output A custom res of 1920x817 @48hz YcBcR 4:2:2 to A correctly calibrated low hour G70 + Moome HDMI/Gamma combo...

This will get you pretty much the best picture A G70 can produce the end result will Yield A super sharp picture compared to inputing 1080p @ 60hz from A Blu-Ray....


Cheers...
 

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Quote:
Originally Posted by rajdude /forum/post/15413684

As for 48Hz refresh....... Are you sure you are displaying that refresh rate on the G70?

When I tried 1920x1080p @ 48Hz yesterday, the PJ did sync up but the image was flickering a lot.....definitely not watchable.

Hi Rajdude,

I can say that 1080p48 with reduced porches is OK on G70



Try these parameters in Powerstrip:

Freq.H = 53.946KHz

Sync.V = 47.952Hz

Pixel rate = 118.681MHz

Syncs = H+/V+

Hsize=1920

Vsize=1080


Porchs values :

H_Front=88

H_sync=44

H_Back=148

-----------

V_Front=4

V_sync=5

V_back=36


With these parameters while watching HD, it's very difficult to see the 48Hz flicker at 1080p48. On Windows desktop, it's flickering, yes, but almost no flicker when playing HD...

1080p48 @ 118MHz is really delivering a very sharp picture (because pixelclock is under 120MHz) and judderfree. Thanks to the reduced video porches setting that reduce the flicker very well ...


I've been using this setting on G70 (and now on my G90) for years to watch HD-DVD or BR material



John
 

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Discussion Starter · #5 ·
Hi John,

Thanks a lot for these tips!

I will try it out.


May I ask what video card you have?


Last I checked, Powerstrip did not work with newer nVidia cards.

Quote:
Originally Posted by JohnHWman /forum/post/15413891


Hi Rajdude,


I can say that 1080p48 with reduced porches is OK on G70



Try these parameters in Powerstrip:

Freq.H = 53.946KHz

Sync.V = 47.952Hz

Pixel rate = 118.681MHz

Syncs = H+/V+

Hsize=1920

Vsize=1080


Porchs values :

H_Front=88

H_sync=44

H_Back=148

-----------

V_Front=4

V_sync=5

V_back=36


With these parameters, for me it's very difficult to see the 48Hz flicker at 1080p48 so image is very sharp (pixelclock is under 120MHz) and judderfree. Thanks to the reduced video porches setting that reduce the flicker very well ...


I've been using this setting on G70 (and now on my G90) for years to watch HD-DVD or BR material



John
 

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Some alternatives:


1920 x 1080i at 95.904 hz Similar to 1080p 48hz but no FLICKER.


PowerStrip timing parameters:

1920x1080=1920,112,128,115,1080,46,5,30,126655,542


Generic timing details for 1920x1080:

HFP=112 HSW=128 HBP=115 kHz=56 VFP=46 VSW=5 VBP=30 Hz=48


VESA detailed timing:

PClk=126.66 H.Active=1920 H.Blank=355 H.Offset=96 HSW=128 V.Active=1080 V.Blank=81 V.Offset=46 VSW=5


Linux modeline parameters:

"1920x1080" 126.655 1920 2032 2160 2275 1080 1126 1131 1161 interlace -hsync -vsync






1920 x 802p at 71.928hz



"C:\\Program Files\\PowerStrip\\PStrip.exe" /t:1920,138,64,154,802,7,3,18,135877,534
 

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Quote:
Originally Posted by rajdude /forum/post/15414364


May I ask what video card you have?

I've been using Powerstrip with ATI card on my first HTPC. Then for my second (G35) and now my third HTPC (G45), I'm using Intel embedded graphics (IGP) and tweak it (like powerstrip does) with DTD Calculator.

John
 

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Discussion Starter · #8 ·
I tried it last night and I have one word.

WOW !
  • Scanlines on 1080p !
  • No flicker (I get no flicker even on my desktop)
  • I can read everything on the SMPTE RP 133 Resolution Chart

Thanks a million for the tip, John!


I don't have powerstrip. My nVidia drivers have these fields I can change in the manual mode. The only fields I did not see are the ones in red below:


Freq.H = 53.946KHz

Sync.V = 47.952Hz

Pixel rate = 118.681MHz

Syncs = H+/V+

Hsize=1920

Vsize=1080


Porchs values :

H_Front=88

H_sync=44
H_Back=148


-----------

V_Front=4

V_sync=5
V_back=36


Still I was able to get it working fine.

Anyone who is after 1080p should try this out.


Video was very smooth earlier (720p @ 60HZ), but now it is even smoother WOW!


I know lot of people here want to do 1080p at 72Hz. After yesterday night, I am wondering, why bother? Why stress out the electronics further.


Now for the curiosity-killed-the-cat question:


What the heck are porches and why reducing them gets rid of the flicker at low refresh rates?


googling porches....
 

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Quote:
Originally Posted by rajdude /forum/post/15421767


What the heck are porches and why reducing them gets rid of the flicker at low refresh rates?


googling porches....

The way I understand it is, it flickers less is because the projector spends less time off before it redraws the image again.


smaller porches = less off time



Ok, here is my question....Let's say you have a stack like Cliff's but 8" projectors both running 48Hz but somehow you could make the 2 projectors retrace times out of phase, would the results be less flicker?


Mike
 

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Discussion Starter · #10 ·
Mike,

your idea may work but how do you make them out of phase?


Also I am never a fan of stacks.....it makes an already soft image softer.

I mean CRT PJs throw a soft image (compared to dPJs)


Stacking them makes them even softer.


I suspect your solution may make a stack even more soft.

Quote:
Originally Posted by MikeEby /forum/post/15422777


The way I understand it is, it flickers less is because the projector spends less time off before it redraws the image again.


smaller porches = less off time



Ok, here is my question....Let's say you have a stack like Cliff's but 8" projectors both running 48Hz but somehow you could make the 2 projectors retrace times out of phase, would the results be less flicker?


Mike
 

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Quote:
Originally Posted by rajdude /forum/post/15423151


Mike,

your idea may work but how do you make them out of phase?


Also I am never a fan of stacks.....it makes an already soft image softer.

I mean CRT PJs throw a soft image (compared to dPJs)


Stacking them makes them even softer.


I suspect your solution may make a stack even more soft.

Your right about the sharpness, however when I look at the 1:1 pattern at 48Hz on my XG is way better then at [email protected] because of less bandwidth requirements for 48Hz the flicker on an XG is unbearable at 48Hz with any porch settings that will sync correctly. Getting the 2 projectors out of phase....Any ideas...anyone?


Mike
 

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Discussion Starter · #12 ·
I guess you have already tried the porch settings above, right?


I wonder why a G70 would sync to these porch settings and not flicker.....but a XG wont.


Design/electronics difference?

Quote:
Originally Posted by MikeEby /forum/post/15423248


...........the flicker on an XG is unbearable at 48Hz with any porch settings that will sync correctly.


Mike
 

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Hi

I just got my g-70 up with a PS3 for bluray and the new hdmi card from moome and it is doing 1080P pretty well. Picture looks much better than when I ran 720 thru an older crystal image. Churchuf came over to redo the setup with the new output. My g has about 3K hrs on it but I was surprised at how well the image is at 1080p.


Bob
 

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Quote:
Originally Posted by rajdude /forum/post/15423608


I guess you have already tried the porch settings above, right?


I wonder why a G70 would sync to these porch settings and not flicker.....but a XG wont.


Design/electronics difference?


G70 has a shorter retrace.


The XG has a pretty picky deflection system. My PG Xtra was more robust - much less likely to foldover or raster ring on the LHS.
 

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Quote:
Originally Posted by rajdude /forum/post/15423151


Ok folks, the tweak-bug bit me again!


I have a Sony G70 fed by a HTPC outputting 720p / 60Hz. I have been very happy with it and have not done anything to it for more than a year.


However I am curious if this can do 1080p..

Have you tried [email protected]? or [email protected]?


Ken W setup 720p/72 on Wallace's 9PG next door and it looks great.

Quote:
Originally Posted by rajdude /forum/post/15423151


Mike,

your idea may work but how do you make them out of phase?


Also I am never a fan of stacks.....it makes an already soft image softer.

I mean CRT PJs throw a soft image (compared to dPJs)


Stacking them makes them even softer.


I suspect your solution may make a stack even more soft.

My storage closet recently restocked... I've recently got some G70's if you want to experiment with a 48Hz x 2 stack. Or 1080i/60 x2.

Or 1080i x4.
 

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Quote:
Originally Posted by Clarence /forum/post/15442404


Have you tried [email protected]? or [email protected]?


Ken W setup 720p/72 on Wallace's 9PG next door and it looks great.




My storage closet recently restocked... I've recently got some G70's if you want to experiment with a 48Hz x 2 stack. Or 1080i/60 x2.

Or 1080i x4.

That is one hell of closet...I'm sure AR will take them off your hands.


Mike
 

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Quote:
Originally Posted by MikeEby /forum/post/15443436


That is one hell of closet... I'm sure AR will take them off your hands.

The G70's are currently parked in a corner of my boys' playroom.


Yeah, AR said he wanted to live next door, plus he'd be closer to Wallaces BBQ.
 

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Wow four G70's



How are the tubes?
 

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Quote:
Originally Posted by Fellenz /forum/post/15448724


Wow four G70's



How are the tubes?

Down boy!



Mike
 

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Quote:
Originally Posted by Clarence /forum/post/15442404


Have you tried [email protected]? or [email protected]?


Ken W setup 720p/72 on Wallace's 9PG next door and it looks great.




My storage closet recently restocked... I've recently got some G70's if you want to experiment with a 48Hz x 2 stack. Or 1080i/60 x2.

Or 1080i x4.

Rajdude,

You need to come up here and see our HT. We are planning on having a "mini-meet" here soon and I'll let you know what the date is.


Ken Whitcomb did an outstanding job setting up our nec 6pg xtra. I hope to get him out here soon for some other work and I would think he could work his magic on your pj as well.


wallace
 
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