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Discussion Starter · #1 ·
I was told my thread would be better received here rather than the HTPC section so here it is again:


Hey everyone here is my first post. Been reading up on the site, but couldn't find an answer for this seemingly simple problem. I have an AmPro 2000G CRT projector and an HTPC (soyo dragon plus, Radeon 8500, AMD 1.2, 256 Crucial, Toshiba DVD, onboard sound). My question is this: First off just to clear things up I understand that you have to pull back to make the screen bigger and forward for smaller (not that helpless ). I followed the manual for exact measurement for table mount from floor and from screen for an 84-inch wide screen. In test mode while aligning the CRT's the picture fit the screen perfectly, but when I hooked up the HTPC through the 5 BNC from VGA connection the picture was way off to the left and there was a total of about 24 inches of screen not filled up between the left and the right of the screen. I tried making the screen larger with both the internal AMPRO electronic adjustments and with powerstrip, but maxing both of them out still leaves me with a picture that is to small (although I can center it using these fixes.) I am confused because when I center it like this then turn the test screen back on that is way off the screen now. I think it is obvious that I am missing something here! Please Help


One more thing, I am a little worried about CRT burn using Windows because desktop icons and the start menu are constantly on the screen. Also right now when I play a dvd through Power DVD there are the black bars on the top and bottom for the 16:9 screen size, will these black bars cause CRT burn?


Thanks,

DAN
 

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Say Dan


Welcome on board to the Forum; sounds like you have a few issues here. I don't know the Ampro machines, but chances are there is an H Centering or H Phase control somewhere that will allow you to center the image. If you a have a 4:3 screen and show a 16:9 movie then you will have black bars top and bottom. I shall let the Ampro gurus run with this from here.
 

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Discussion Starter · #4 ·
ThurmanWitte,


Thank you. I got your previous reply. The problem is I've tried those back porch settings and such with powerstrip... have those just about to the limit and it is still coming up fairly short on width. So I've pulled the projector back about another 12 inches to make up the difference. To my knowledge it is still not using all the phosphor (if that is the correct term) because the test image is still larger than my tweaked image with power strip. I also have the Ampro's width tweak at 95%. Is it bad to not use all the phosphor?

I also posted this message again because I wanted more info. on the black bars in 16:9 mode and whether or not these black bars pose CRT burn risk. I thought the Gurus here on the CRT threads would have more knowledge on the using all the phosphors and black bar burn threat questions.


Thanks,

DAN
 

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Is the power strip outputing a 4:3 aspect ratio and the progector is set to 16:9?


This was sort of the problen I had with my 13031Q at initial set up. I had a 16:9 screen and was only running composit video (yuch) at first then I was informed how incredible the 1031Q is with a doubler so I got a doubler :)


My image all of a sudden went from fitting the screen perfectly with the test pattern and video image to being WAY to small.


I think that when you go from composit input to an RGB input or for that matter internal test generator to an external source (HTPC) you have to set up from the source and not rely on the internals. I am not really knowlegable with HTPC so I wont say anymore about that, but this may be a good place to start checking the set up. See what ratio the projector is set up for and then see what your feeding the projector.


Oh yea, the windows task bar and what ever else you see of windows will eventually burn i nif it is ON ALL THE TIME (not good) anything for that matter that is static, does not move will eventually burn in. If you watch 16:9 all the time and you have a 16:9 screen there should not be any bars, but it sounds as if your on a 4:3 screen? Again if your watching 16:9 format all the time there really is no black bars on the face of the CRT just an aspect ratio area of 16:9. you see bars because of the screen. If you flip between aspect ratios 16:9 and 4:3 often enough there wont be too much to worrie about. If you search this forum, and Curt Palme just posted some good burnt tubes you can see what will eventually happen to the CRT tubes. If you are running at respectable brightness / contrast levels you could go thousands of hours without burnig the tubes.


Do a search on burn in there have been millions of posts on the subject.


check this out for burn in. You can see the windows dispaly granted the phosper area was set up all wrong, but more importantly you can see 4:3 burn.

http://www.avsforum.com/avs-vb/attac...postid=1063065
 

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Dan,


Vic has a good point. The aspect ratio from the HTPC needs to match your screen.


You also need to stick with the distance the manual specifies for your screen width.


I am currently running my HTPC at [email protected] on a 16:9 80"x45" screen. You don't say what your settings are. Before I tried my current settings I was running [email protected], which produced a default image smaller than the 48Hz setting. You might want to give the 48Hz setting a try.


On your initial post you say "In test mode while aligning the CRT's the picture fit the screen perfectly". Do you mean the test pattern, or at the point in the guided setup procedure where the projector shows just the green tube with the picture of the current source so you can get the proper H and V size and position?

When I am adjusting my projector, it is normal for the test patterns to be larger than the screen.


I currently have my Ampro width set at 95, so I think you are OK there. If I go much beyond 95, the upper part of my picture begins tearing. It is kind of hard to tell by looking through the lenses how much phosphor I am using, but I would say mine is maybe a quarter inch from the edge.


Before I started messing with the porch settings my projected screen width was about 8" too narrow on both sides. It took a lot of experimenting with the porch settings on my HTPC to finally determine how to max out the width of the projected size. I tried dozens of different combinations. Be prepared to cancel out of the powerstrip setting you are testing on the HTPC if you pick one the projector does not like. You will probably have to adjust the horizontal phase on the Apmro when you pick a new powerstrip setting, which becomes tedious after a while.


If you have an HDTV source to input to the projector it will give you a picture much wider than what you will get from the HTPC with the default settings on powerstrip, but it will also show you how wide you should be able to get the HTPC image.


When you first started the alignment and convergence process were all the settings for size, position, keystone, pincushion, shift, phase etc. at their midpoints (i.e. a value of 50)? Were the left and bottom blanking values set to 0 and the top and right set to 100?

It took me a long time to get the hang of converging my projector. Part of my initial difficulty was the inter-relation of the functions with each other such as size, line, and edge.
 

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Also remeber this, image width and Raster size are not the same thing.

Your Raster should sit centered on the tube face, without touching any edge to the tube...the picture should sit inside that raster area.


With contrast turned way down and Brightness way up, you should see raster all around your picture.

If you can see the Raster lit up around your picture, how much Raster would you say is surrounding your picture?

As your resolution (or refresh rate) increases picture size gets smaller, so either pj must be moved back or horizonal and vertical sizing adjustments must be increased. At a horizonal size of 95% I don't think I'd increase that any more.

Realize that picture size is never as large as your grid patterns.


If however, your pj is sitting 12" farther back than the factory spec's...there is something set wrong
 

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Dan, something else you may want to consider...at a setting 95% of max width, you are running that circut at 95% of it's max operating voltage (or at least some part of it)...and for these Ampros,perhaps 95% is closer to 100%...perhaps this picture breakup is a "clipping" condition.

I am learning a 3600 right now, and it has that same "tearing" Thurman speaks of at 97%

My XG has no such problem...but, I've been on it's H width pots and set them to the correct factory voltages...perhaps the Ampro's need calibration in this area.

It may be wise to keep that horizonal amplitude closer to 90%...this gives that circut a little operating cushion.
 

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Discussion Starter · #9 ·
Thanks for throwing some ideas around guys. I was wondering if you could further on the 16:9 ratio thing. I have an 84 inch by 84 inch screen, but am really only interested in watching 16:9 movies and don't really care if there is some white screen above the projected image. I am wondering how to do a 16:9 screen without the black bars. I am feeding the projector a 72 hz signal, which could be the reason that the image is smaller as ThurmanWitte suggested. However, reading on this fourm I saw that 72hz was the point where the human eye can't see any flicker. If this is true I would rather try solving the problem staying at the 72hz level. Also I have tried playing with the different screen sizes with powerstrip such as 1280X720... on my computer screen this gives me an image that is way off the screen and I have to scan left and right with the mouse in order to get to either end of the desktop (by the way I have the projector and my computer screen hooked up at the same time using the second video out on the Radeon 7500). The projected image of the Ampro 2000G does the same thing, it shows exactly what the monitor is showing and as I scan back and forth with the mouse it reveals the rest of the desktop. Is there a way to feed the whole 16:9 image to the projector so it displays the whole desktop at this ratio without having to scan back and forth? Again I think I'm missing something.


Thanks again,

DAN
 

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I'm not quite sure what you mean by "scan left and right".

Is the monitor filled, but the entire desktop is not being shown and you have to "pan" left and right? If so, then something is not set properly in Windows. I've come across that before, but it has been a long time and I can't remember the way to fix it.

OR

Do you have part of the image cut off on one side of the monitor, and the other side of the monitor you have a black area equal in size to what was cut off.


You may need to go over to the HTPC forum and ask specifically about the Radeon and the problem you are having.


For 16:9 you need to have the computer set to a resolution which is a 16 x 9 ratio. The 1280 x 720 is 16:9, so you will be OK with it. You then need to adjust the vertical height of the projected image to get a 16 x 9 ratio. Measure the width of the projected image and then determine the height necessary for 16:9. If you are getting an 84" wide image, you will need a height of 47.25". Use something like masking tape to temporarily mark the top and bottom of the 47.25" portion of the screen where you want the projected image to be. Use the Ampro remote to (1)reduce the master vertical height to get 47.25", and (2)vertical shift the image to the proper spot. The vertical size and shift are part of the guided registration process on the Ampro, so it might be simpler to do it that way.
 

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Discussion Starter · #11 ·
"Pan" left and right is what I mean. More problems more fun! Just upgraded to windows XP and now my remote program I was running doesn't work! Here we go again!


DAN
 

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If you have to pan the desktop around to see everything then you have Windows convinced that your display device isn't capable of the resolution you are attempting to display - look in your advanced settings of the display properties and see if you have the monitor type set to 'TV' or something like that. If it's set to 'analog monitor' then I don't think this will happen...
 

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Discussion Starter · #13 ·
Ok. Running at 1280X720 @ 72 HZ without haveing to pan now... However the picture is still to small for the screen (tried changing to 45 hz and also messed with front/back porch settings to no avail). Also are you guys sure there isn't suppose to be black bars at all at the top and the bottom of the screen while playing 16:9 DVD's in PowerDVD? I've tried everything (at least everything I know how to do :) ). The only thing that works is selecting "Pan & Scan" in PowerDVD and then going to "2.25:1" I don't even know what that means. It is weird because the FBI warning and so forth all fit the screen perfectly, but they aren't 16:9 which is what my screen should be running 1280X720. Any ideas?
 

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Discussion Starter · #14 ·
Sorry... just wanted to clear this up real quick. The FBI warning doesn't "fit perfectly" like I said. It eliminates the black bars on the top and bottom of the screen as does the Pan & Scan solution, yet the picture still comes up short as far as filling up my screen width. I have since pushed my projector back to the distance from the screen stated in the manual, leaving me with my original problem of the width coming up short still.


DAN
 

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A 2.35:1 aspect ratio will give you black bars on top and bottom when you have a 16:9 screen. Get a DVD with a 16:9 aspect ratio (try a Warner Brothers DVD which says "Enhanced for Widescreen") and see if the output from PowerDVD when playing the movie is 16:9 on your screen.


You may want to try YXY to make adjustments to the aspect ratio. You can find it here:
http://www.keohi.com/keohihdtv/htpc/yxy/yxy.html
 

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Discussion Starter · #16 ·
I'm using Gladiator for my tests... it says WIDESCREEN huge down at the bottom... and I know for a fact it is wide screen because I've watched it on my regular tv with the black bars at the top and bottom. I was thinking maybe powerstrip was just telling me I was in 1280X720 and I really wasn't, but I went to properties for the video card and it says I'm doing 1280X720 in there also. I guess the only answer is that I am somehow still not in 16:9 format though, because like I said the FBI warning which is not 16:9 has no black bars, and now you're telling me that the 2.35:1 converts 16:9 to whatever "normal" ratio is 4:5 or something like that, which for me gets rid of the black bars. Makes no sense...


DAN
 

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If the DVD says the aspect ratio is 2.35:1, it means the movie is 2.35:1. The FBI screen and the DVD setup/option screens are not the aspect ratio of the movie (unless the AR of the movie is 16:9).


Quite a few DVDs explicitly state the AR, the Warner Bros DVDs do not, they just say enhanced for widescreen (some of the newer WB DVDs are starting to give the AR). The Warner Bros movies that say they are enhanced for widescreen and do not give an AR, are stored on the DVD in 16:9 even if the movie is a 2.35:1. The black bars are stored along with the movie on these DVDs. Just the actual movie is recorded on an anomorphic DVD, the black bars are not - they leave it up to the DVD player/display device to do a vertical squeeze to display it properly.


Find a non-anomorphic DVD with a 16:9 AR so you can get all of the HTPC adjustments/sizing for 16:9 worked out without having to worry if the HTPC and PowerDVD are doing the anamorphic processing properly.
 

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Discussion Starter · #18 ·
Let me see if I have this straight... are you saying that even though the movie says it is 16:9 it was made to play 16:9 aspect ratio on a 4:3 ratio screen? So no matter what there will be black bars at the top and bottom? I looked at the black of Gladiator it says it is Anomorphic 2.35:1 so you're right if I have the theory correct. What should I be looking for on the back of the dvd to find one that is not Anomorphic. I have one here that says it "a widescreen version and preserves the original theatrical aspect ratio approximately 1.85:1" I saw this 1.85:1 setting in powerDVD as well, can you tell me what that is as well?

I have a bunch of DVD's maybe you could also give me a few titles that you know to be in "True" 16:9 format.


Thanks,

DAN
 

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The setting of the display device is what is important, i.e. your projector and HTPC. You have these set for 16:9 (or will once you have the projector setup properly)


The only time you will have 4:3 is when the DVD states "full frame" or "formatted to fit your screen" (they should be saying "butchered to fit your NTSC TV", because they sure aren't talking about my screen)


From your discussion in this and other threads I am under the assumption you have an 84"x84" screen and your HTPC is set at 1280 x 720 (16:9) and you are trying to set your projector up for 16:9.

You need to adjust the projector to give you an image size 84" wide x 47.25" high. This is why you need a DVD which will provide a 16:9 picture.

See if you have any Warner Bros DVDs and check the case. If it says "enhanced for widescreen" and does not give an AR, it should be 16:9.
 

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Quote:
are you saying that even though the movie says it is 16:9 it was made to play 16:9 aspect ratio on a 4:3 ratio screen? So no matter what there will be black bars at the top and bottom?
Indeed. The "16:9" refers to the aspect ratio of the display device. The actual aspect ratio of the movie itself may differ, and in this case it does.
 
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