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Anyone else have this problem with 720p?
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Kiev Savoie



Joined: 25 Oct 2007
Posts: 432


Posted: Sun Dec 13, 2009 2:26 am    Post subject: Anyone else have this problem with 720p?

I have had my PS3/RTC2200/G70 setup running in 1080i almost exclusively for TV and movies. Recently my neighbor gave me a game to try which, like most PS3 games is 720p. My projector wants to squeeze 720p down so that I can not make it fill the entire screen like 1080i. My solution to this was to uncheck 720p as a display resoultion in the PS3 settings menu, so now I guess it is upscaling to 1080i. which is fine with me... unless there are situations where i would be stuck with 720p as my only option. If there is anyone out there who has dealt with this issue please chime in.
Thanks
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AnalogRocks
Forum Moderator


Joined: 08 Mar 2006
Posts: 26706
Location: Toronto, Ontario, Canada

TV/Projector: Sony 1252Q, AMPRO 4000G

Posted: Sun Dec 13, 2009 2:35 am    Post subject: Re: Anyone else have this problem with 720p?

Kiev Savoie wrote:
I have had my PS3/RTC2200/G70 setup running in 1080i almost exclusively for TV and movies. Recently my neighbor gave me a game to try which, like most PS3 games is 720p. My projector wants to squeeze 720p down so that I can not make it fill the entire screen like 1080i. My solution to this was to uncheck 720p as a display resoultion in the PS3 settings menu, so now I guess it is upscaling to 1080i. which is fine with me... unless there are situations where i would be stuck with 720p as my only option. If there is anyone out there who has dealt with this issue please chime in.
Thanks


Hi Keiv,
The PS3 downscales 720p to 480p.

What aspect ratio screen do you have?

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Mark_A_W



Joined: 15 Mar 2006
Posts: 3068
Location: Sunny Melbourne Australia

Posted: Sun Dec 13, 2009 6:12 am    Post subject:

With a CRT you really do need a video processor or a PC.
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ecrabb
Forum Moderator


Joined: 13 Mar 2006
Posts: 15909
Location: Utah

TV/Projector: JVC RS40, Epson 5010

Posted: Sun Dec 13, 2009 3:23 pm    Post subject:

Come on, Mark... It totally depends on your sources, and if you're sensitive to judder or not. I run 1080p/60, and very rarely ever see judder. I'm certainly not going to spend $2000 to get a scaler to run 72 or 96hz. If you run a normal set-top BD player (as opposed to a PS3), it'll lock and stay at 720p/1080i/1080p, and you're not sensitive to judder, you'll never have an issue.

The PS3 is just a pain in the ass because it's all over the place on resolution, depending on the source: BD, BD w/SD content, games, etc.

Kiev, I run PS3 games on my G70 (including 720p), and I've never had the problem you're talking about. Are you sure your raster is set up correctly? Your problem sounds like the problem I had when I set up the internal patterns to match the screen size. I read that was a bad idea, and once I pushed the internal pattern way out beyond the screen borders, then everything else worked much better. I assume it's a problem with pushing the active image area to close to the edge of the raster.

SC
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CIR Engineering



Joined: 25 Aug 2008
Posts: 4269
Location: Chicago USA & Berlin Germany

Posted: Sun Dec 13, 2009 3:56 pm    Post subject:

I agree with Mark that you really should run a VP with a CRT. It's not just about sources and their resolutions, it is a question of convenience. With a VP you input all your sources into it and the VP outputs a scan rate that is then consistent with ALL your sources. This way the timings are the same with all your sources and there are no new memories needed every time you change scan rates, sources, or add new devices. You can then also run 817x1920 at either 60 Hz or 72 Hz to eliminate judder or sharpen the image (817x9120 60Hz is sharper than 1080p 60 Hz for 2.35 movies).

Also, with a VP like a Lumagen or DVDO you get a built in pattern generator. It is highly convenient to have a pattern generator always connected to the CRT.

Used Lumagen VisionHDP series processors can be had on eBay these days for $200 ~ $500 and they are very capable. They are the cheapest processor that can do true IVTC and extract 72Hz from 60Hz sources like DVD. The VisionHDP also supports any custom timing you want and has a great pattern generator.

craigr

_________________
JETI 1501-HiRes 2nm Spectroradiometer
JETI 1211 Spectroradiometer
Photo Research PR-650 Spectroradiometer
Klein K10-A Colorimeter
Murideo Fresco SIX-G HDMI 2.x Multimedia Generator
Murideo Fresco SIX-A HDMI 2.x Analyzer
Light Illusion ColourSpace XPT Color Calibration Software
Light Illusion LightSpace XPT Pro Version 10.x Color Calibration Software
OMARDRIS JVC Software Patch to use K10-A and Jeti with JVC OEM AutoCal Software!
Sencore CR7000 CRT Tube Analyzer / Rejuvenater
Authorized Dealer for Lumagen & just about everything worth buying Wink
www.CIR-Engineering.com - craigr@cir-engineering.com
Phone: 865-405-6892
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ecrabb
Forum Moderator


Joined: 13 Mar 2006
Posts: 15909
Location: Utah

TV/Projector: JVC RS40, Epson 5010

Posted: Sun Dec 13, 2009 4:08 pm    Post subject:

Craig... I don't disagree with the essence of what you're saying - running 817x1920 @ 72 is great for sharpness and frame rate matching. But, convenience? Come on. So, I need to configure a memory and res/refresh for every aspect ratio, then switch those every time I switch from a 1.85 movie to a 2.40 movie, and back to a 16:9 game. Yeah, my wife will love that "convenience".

That said, I do have a processor - just not a standalone. I have the Reon HQV in my Integra prepro... So, I can force everything to one resolution, as long as it's 720p or 1080p.

Oh, with the PNGs on my PS3, I have a built-in pattern generator, too! Wink

So, does the $200-500 used Vision HDP take a 1080p/24psf input, and output cropped 1920x817/48 or 72? Can it do IVTC on 1080i?

SC
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macgyver655



Joined: 22 Aug 2007
Posts: 8508


Posted: Sun Dec 13, 2009 4:26 pm    Post subject:

Hmmmmmmm......... Very Happy
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CIR Engineering



Joined: 25 Aug 2008
Posts: 4269
Location: Chicago USA & Berlin Germany

Posted: Sun Dec 13, 2009 7:10 pm    Post subject:

ecrabb wrote:
Craig... I don't disagree with the essence of what you're saying - running 817x1920 @ 72 is great for sharpness and frame rate matching. But, convenience? Come on. So, I need to configure a memory and res/refresh for every aspect ratio, then switch those every time I switch from a 1.85 movie to a 2.40 movie, and back to a 16:9 game. Yeah, my wife will love that "convenience".

That said, I do have a processor - just not a standalone. I have the Reon HQV in my Integra prepro... So, I can force everything to one resolution, as long as it's 720p or 1080p.

Oh, with the PNGs on my PS3, I have a built-in pattern generator, too! Wink

So, does the $200-500 used Vision HDP take a 1080p/24psf input, and output cropped 1920x817/48 or 72? Can it do IVTC on 1080i?

SC

It can be very convenient... On a Lumagen you can choose to just run EVERYTHING 1080p 60Hz if you want. That way every single source uses the exact same output timings and only one memory is required in the projector for everything you ever connect to the projector.

Furthermore, on the Lumagen you set up a second output scan rate of 817x1920 72Hz that automatically starts when you just push the 2.35 button on the remote. Two scan rates is not at all complicated and only requires that you press either 16x9 or 2.35 on the Lumagen remote... and if you default everything to 16x9 1080p 60Hz output your wife does not have to do anything ever to change anything if she wishes not to Wink

And yes, the VisionHDP, VisionHDQ, and VisionHDPPro all can take 1080p 24Hz input and output 1920x817 72 Hz. And the three can all do IVTC on both 1080i and 480 i/p. The VisionHDP series can also support 1080p 72Hz through the RGBHV output if you don't use HDMI.

craigr

_________________
JETI 1501-HiRes 2nm Spectroradiometer
JETI 1211 Spectroradiometer
Photo Research PR-650 Spectroradiometer
Klein K10-A Colorimeter
Murideo Fresco SIX-G HDMI 2.x Multimedia Generator
Murideo Fresco SIX-A HDMI 2.x Analyzer
Light Illusion ColourSpace XPT Color Calibration Software
Light Illusion LightSpace XPT Pro Version 10.x Color Calibration Software
OMARDRIS JVC Software Patch to use K10-A and Jeti with JVC OEM AutoCal Software!
Sencore CR7000 CRT Tube Analyzer / Rejuvenater
Authorized Dealer for Lumagen & just about everything worth buying Wink
www.CIR-Engineering.com - craigr@cir-engineering.com
Phone: 865-405-6892
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Mark_A_W



Joined: 15 Mar 2006
Posts: 3068
Location: Sunny Melbourne Australia

Posted: Mon Dec 14, 2009 6:24 am    Post subject: Re: Anyone else have this problem with 720p?

Kiev Savoie wrote:
I have had my PS3/RTC2200/G70 setup running in 1080i almost exclusively for TV and movies. Recently my neighbor gave me a game to try which, like most PS3 games is 720p. My projector wants to squeeze 720p down so that I can not make it fill the entire screen like 1080i. My solution to this was to uncheck 720p as a display resoultion in the PS3 settings menu, so now I guess it is upscaling to 1080i. which is fine with me... unless there are situations where i would be stuck with 720p as my only option. If there is anyone out there who has dealt with this issue please chime in.
Thanks



Oh, and nobody told you what is going on...


Basically, the 720p timings have too many or too few porch pixels - pixels off the side of the image, not visible.

If the image is cropped, then it's too few porch pixels and your projector has not got a fast enough retrace to get the whole image in.

If the image is just too small, then there are too many porch pixels and the deflection can't go wide enough.



The solution is a custom resolution, and yup, that means a VP or a PC.
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cinema mad



Joined: 25 Nov 2009
Posts: 219


Posted: Mon Dec 14, 2009 7:08 am    Post subject:

Yep, I had the same issue as mark discribes with my G70 running SD DVD Pal 50Hz scaled up to 720p @75Hz..

Once I set up A custom 720p timing (changed porches) with my vp50pro the G70 displays 720p @75Hz perfectly thus the need for A VP with the capability of setting up custom timings... 720P prob gives use the biggest headache without A means of runing A custom timing'/ changing porches...

Cheers...
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CIR Engineering



Joined: 25 Aug 2008
Posts: 4269
Location: Chicago USA & Berlin Germany

Posted: Mon Dec 14, 2009 4:06 pm    Post subject:

Basically 720p was a real PITA and wasn't ever really meant for CRT to display. That's why all the rear projection CRT's only display 1080i (or something similar).

craigr

_________________
JETI 1501-HiRes 2nm Spectroradiometer
JETI 1211 Spectroradiometer
Photo Research PR-650 Spectroradiometer
Klein K10-A Colorimeter
Murideo Fresco SIX-G HDMI 2.x Multimedia Generator
Murideo Fresco SIX-A HDMI 2.x Analyzer
Light Illusion ColourSpace XPT Color Calibration Software
Light Illusion LightSpace XPT Pro Version 10.x Color Calibration Software
OMARDRIS JVC Software Patch to use K10-A and Jeti with JVC OEM AutoCal Software!
Sencore CR7000 CRT Tube Analyzer / Rejuvenater
Authorized Dealer for Lumagen & just about everything worth buying Wink
www.CIR-Engineering.com - craigr@cir-engineering.com
Phone: 865-405-6892
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draganm



Joined: 08 Mar 2006
Posts: 8990
Location: Colorado

Posted: Mon Dec 14, 2009 4:35 pm    Post subject:

ecrabb wrote:
Your problem sounds like the problem I had when I set up the internal patterns to match the screen size. I read that was a bad idea, and once I pushed the internal pattern way out beyond the screen borders, then everything else worked much better. I assume it's a problem with pushing the active image area to close to the edge of the raster.
SC
Good point. I didn't even think it was possible to have active image and raster the same size? The raster should always be a little larger IMO.
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ecrabb
Forum Moderator


Joined: 13 Mar 2006
Posts: 15909
Location: Utah

TV/Projector: JVC RS40, Epson 5010

Posted: Mon Dec 14, 2009 5:37 pm    Post subject:

Weird. Why are you guys having so much trouble with 720p? I run 720p from the HTPC with standard HD timings, and I have no problem at all. Nor, do I have any problem with the PS3 at 720. What's the deal?

CIR Engineering wrote:
Basically 720p was a real PITA and wasn't ever really meant for CRT to display. That's why all the rear projection CRT's only display 1080i (or something similar).


Craig, weren't the ATSC standards for 1080i and 720p developed almost 15 years ago? There was hardly anything but CRT back then!

I always assumed it was a matter of cost (for little direct benefit) that the RPTV manufacturers chose to exclude 720p as a usable input resolution.

SC
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Axatax



Joined: 01 Nov 2006
Posts: 403


TV/Projector: Sony VPH-G70Q (aka Barco Cine8 Onyx)

Posted: Tue Dec 15, 2009 4:16 am    Post subject:

Quote:
Weird. Why are you guys having so much trouble with 720p?


Because the OP is running at 720p50 (note the 50) - this is problematic on most sets. Very Happy
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AnalogRocks
Forum Moderator


Joined: 08 Mar 2006
Posts: 26706
Location: Toronto, Ontario, Canada

TV/Projector: Sony 1252Q, AMPRO 4000G

Posted: Tue Dec 15, 2009 4:49 am    Post subject:

Many of the PS3 games are 60Hz only. So even if you have your PS3 set to 720p/50 when the game fires up it will switch to 720p/60.
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CIR Engineering



Joined: 25 Aug 2008
Posts: 4269
Location: Chicago USA & Berlin Germany

Posted: Tue Dec 15, 2009 2:48 pm    Post subject:

ecrabb wrote:
Weird. Why are you guys having so much trouble with 720p? I run 720p from the HTPC with standard HD timings, and I have no problem at all. Nor, do I have any problem with the PS3 at 720. What's the deal?

CIR Engineering wrote:
Basically 720p was a real PITA and wasn't ever really meant for CRT to display. That's why all the rear projection CRT's only display 1080i (or something similar).


Craig, weren't the ATSC standards for 1080i and 720p developed almost 15 years ago? There was hardly anything but CRT back then!

I always assumed it was a matter of cost (for little direct benefit) that the RPTV manufacturers chose to exclude 720p as a usable input resolution.

SC

I can't remember when ATSC came up with 720p / 1080i, it must have been the late 90's. The reason they allow for both 720p and 1080i was to appease two crowds. One crowd wanted resolution and the other wanted progressive for flicker free. I guess you must be correct that 720p was intended for CRT to remove interlaced flicker. The thing is that no rear projection CRT supported 720p natively. They all converted it with an internal scaler to 1080i, of 540p, or something custom. The timings required by 720p are much more strenuous and require better components in the display device and manufacturers didn't think it would be cost effective to implement 720p on consumer grade CRT TV's. Even front projectors run hotter and have a more difficult time with 720p verses 1080i (let's not talk about 1080p).

Conversely, the first good digitals that were available were limited to 720p for years. There really weren't widespread digital sets that supported 1080p until a few years ago. 720p broadcasts would look best on 720p digital because no scaling is required.

720p and 1080i require the same bandwidth to broadcast and is how they were both allowed because they fit inside of a station. I find it very short sighted that stations decided to use 720p at all. We always knew that 1080i only needs to be deinterlaced to extract the full 1080p resolution with zero flicker of a progressive signal. And we pretty much knew that digitals were coming that would support 1080p. Now we are stuck with stations and networks that chose 720p because forever into the future these stations will need to be scaled to 1080 to be displayed on modern devices. The only thing 720p will look its best on is low end or antiquated digitals that are getting older every year and will vanish...

craigr

_________________
JETI 1501-HiRes 2nm Spectroradiometer
JETI 1211 Spectroradiometer
Photo Research PR-650 Spectroradiometer
Klein K10-A Colorimeter
Murideo Fresco SIX-G HDMI 2.x Multimedia Generator
Murideo Fresco SIX-A HDMI 2.x Analyzer
Light Illusion ColourSpace XPT Color Calibration Software
Light Illusion LightSpace XPT Pro Version 10.x Color Calibration Software
OMARDRIS JVC Software Patch to use K10-A and Jeti with JVC OEM AutoCal Software!
Sencore CR7000 CRT Tube Analyzer / Rejuvenater
Authorized Dealer for Lumagen & just about everything worth buying Wink
www.CIR-Engineering.com - craigr@cir-engineering.com
Phone: 865-405-6892
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dturco



Joined: 06 Feb 2009
Posts: 3778
Location: Eastern Shore Maryland

TV/Projector: Runco DLP VX-3000i Marquee 9500 parts doner

Posted: Tue Dec 15, 2009 5:14 pm    Post subject:

So I take it that's why when I am watching Star Trek TNG or Stargate they look the best in 720p { [45 60] [720x1280] } even though they both are 185:1 scope enhanced for HDTV? They both look terrible in 1080i [33 60] or 1080p [67 60] out of adjustment and stretched?
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Zebu Fellenz



Joined: 21 Dec 2006
Posts: 2567


Posted: Tue Dec 15, 2009 5:39 pm    Post subject:

CIR Engineering wrote:

It can be very convenient... On a Lumagen you can choose to just run EVERYTHING 1080p 60Hz if you want. That way every single source uses the exact same output timings and only one memory is required in the projector for everything you ever connect to the projector.

Furthermore, on the Lumagen you set up a second output scan rate of 817x1920 72Hz that automatically starts when you just push the 2.35 button on the remote. Two scan rates is not at all complicated and only requires that you press either 16x9 or 2.35 on the Lumagen remote... and if you default everything to 16x9 1080p 60Hz output your wife does not have to do anything ever to change anything if she wishes not to Wink

And yes, the VisionHDP, VisionHDQ, and VisionHDPPro all can take 1080p 24Hz input and output 1920x817 72 Hz. And the three can all do IVTC on both 1080i and 480 i/p. The VisionHDP series can also support 1080p 72Hz through the RGBHV output if you don't use HDMI.

craigr


Craig,

Quick question. If I got a processor like the Lumagen could I place it between my HTPC and my G70 so when I'm watching a Blu-ray in 2.35:1 or 2.40:1 I could keep feeding 1080p 60 into the lumagen and then feed out 800p 60? I also have some issues with the porches on my 1080p 60 output that the Nvidia control panel won't fix, and powerstrip won't run right on Windows 7. Could the Lumagen be setup to easily fix these problems like I did with powerstrip in the past.

I know most people don't use a processor with a HTPC but the convenience sounds like it may be worth it, in addition to being able to easily add other sources in the future.

Thanks,

Erik
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Spanky Ham



Joined: 22 Mar 2006
Posts: 5643
Location: Comedy Central

Posted: Tue Dec 15, 2009 7:55 pm    Post subject:

CIR Engineering wrote:
ecrabb wrote:
Weird. Why are you guys having so much trouble with 720p? I run 720p from the HTPC with standard HD timings, and I have no problem at all. Nor, do I have any problem with the PS3 at 720. What's the deal?

CIR Engineering wrote:
Basically 720p was a real PITA and wasn't ever really meant for CRT to display. That's why all the rear projection CRT's only display 1080i (or something similar).


Craig, weren't the ATSC standards for 1080i and 720p developed almost 15 years ago? There was hardly anything but CRT back then!

I always assumed it was a matter of cost (for little direct benefit) that the RPTV manufacturers chose to exclude 720p as a usable input resolution.

SC

I can't remember when ATSC came up with 720p / 1080i, it must have been the late 90's. The reason they allow for both 720p and 1080i was to appease two crowds. One crowd wanted resolution and the other wanted progressive for flicker free. I guess you must be correct that 720p was intended for CRT to remove interlaced flicker. The thing is that no rear projection CRT supported 720p natively. They all converted it with an internal scaler to 1080i, of 540p, or something custom. The timings required by 720p are much more strenuous and require better components in the display device and manufacturers didn't think it would be cost effective to implement 720p on consumer grade CRT TV's. Even front projectors run hotter and have a more difficult time with 720p verses 1080i (let's not talk about 1080p).

Conversely, the first good digitals that were available were limited to 720p for years. There really weren't widespread digital sets that supported 1080p until a few years ago. 720p broadcasts would look best on 720p digital because no scaling is required.

720p and 1080i require the same bandwidth to broadcast and is how they were both allowed because they fit inside of a station. I find it very short sighted that stations decided to use 720p at all. We always knew that 1080i only needs to be deinterlaced to extract the full 1080p resolution with zero flicker of a progressive signal. And we pretty much knew that digitals were coming that would support 1080p. Now we are stuck with stations and networks that chose 720p because forever into the future these stations will need to be scaled to 1080 to be displayed on modern devices. The only thing 720p will look its best on is low end or antiquated digitals that are getting older every year and will vanish...

craigr


ATSC was started in the early 90s. There were a lot of people to satisfy and consensus came up with the forty or so formats. I just read a good quote from Margaret Thatcher "Consensus -- the absence or death of leadership." I didn't even know that 352x288 was a format. Anyway, I won't argue the whole 1080i or 720p issue with you. Fox and ABC thought that 60 fps with 720p would give them an advantage with sports.
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Mark_A_W



Joined: 15 Mar 2006
Posts: 3068
Location: Sunny Melbourne Australia

Posted: Tue Dec 15, 2009 9:14 pm    Post subject:

Zebu Fellenz wrote:
CIR Engineering wrote:

It can be very convenient... On a Lumagen you can choose to just run EVERYTHING 1080p 60Hz if you want. That way every single source uses the exact same output timings and only one memory is required in the projector for everything you ever connect to the projector.

Furthermore, on the Lumagen you set up a second output scan rate of 817x1920 72Hz that automatically starts when you just push the 2.35 button on the remote. Two scan rates is not at all complicated and only requires that you press either 16x9 or 2.35 on the Lumagen remote... and if you default everything to 16x9 1080p 60Hz output your wife does not have to do anything ever to change anything if she wishes not to Wink

And yes, the VisionHDP, VisionHDQ, and VisionHDPPro all can take 1080p 24Hz input and output 1920x817 72 Hz. And the three can all do IVTC on both 1080i and 480 i/p. The VisionHDP series can also support 1080p 72Hz through the RGBHV output if you don't use HDMI.

craigr


Craig,

Quick question. If I got a processor like the Lumagen could I place it between my HTPC and my G70 so when I'm watching a Blu-ray in 2.35:1 or 2.40:1 I could keep feeding 1080p 60 into the lumagen and then feed out 800p 60? I also have some issues with the porches on my 1080p 60 output that the Nvidia control panel won't fix, and powerstrip won't run right on Windows 7. Could the Lumagen be setup to easily fix these problems like I did with powerstrip in the past.

I know most people don't use a processor with a HTPC but the convenience sounds like it may be worth it, in addition to being able to easily add other sources in the future.

Thanks,

Erik



Don't use Powerstrip with an Nvidia card, use the Nvidia custom resolution settings.

Unless you want to do something "else" with the Lumagen, it is a total waste fitting it between a PC and a CRT.
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