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General discussion

Digital Projector Questions

Sep 1, 2005 1:23AM PDT

I have wanted a digital projector for a long time. I don't know if I have enough knowledge about them right now to buy one.

I'm looking at the EzPro 739 Micro-Portable DLP Digital Projector . I like this projector because of its resolution,DLP,lamp life, & portability.

It has a resolution of 1024 by 768 which is the resolution my monitor is now. I'm looking at cnet specs and it also says '1400 x 1050 (operating)' What does this mean? My monitor is at 1024 by 768, but with some games I use 800 by 600. Would this projector handle the switch?

I don't have HDTV yet, but when I do, can this projector display a good HDTV picture?

The lamp life is 5000 hrs in economy mode. How realistic is that amount of use? Can economy mode be used all the time(4 hours a day) for a 60" picture in a dim room?

I've read it takes at least 8ft to display a 60" picture with this projector. My room is only 13" long, so I would be sitting fairly close. Since I would be so close, I'm thinking that I really would not want an LCD projector because of the 'screen door effect'. A lot of my movies have dark scenes. I've read that with DLP, the rainbow effect is more noticeable in dark scenes. I don't know I would notice the rainbow effect, but I'm thinking it is less of a problem than the screen door effect.

I like that this projector is portable so I can move it to a place where I can use a larger picture than 60". What exactly makes a projector portable? Since DLP uses thousands of little mirrors, it sounds really fragile. Is it really any more fragile than an LCD projector?

I guess main reason I have not bought a digital projector yet is because of the price. I think prices have been falling, but by how much? Maybe $10 a year on average(just guessing)? Has the price of replacement lamps dropped at all?

If it helps answer any of my questions, I would be using a projector for pc games, dvds, and SDTV TV. My computer has a dvd player and a tv tuner so it would be connected to the same source all the time.

Discussion is locked

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Is this the wrong forum for these questions?
Sep 3, 2005 5:13AM PDT

Doesn't anyone have a front projection tv in their home theater?

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right forum, here are some answers...
Sep 3, 2005 5:44PM PDT

I have a forward projection system in my home theater & I love it. I definitely recommend it. I would suggest either buying a good screen or treating your wall with decent light gray flat paint & putting up black trim as border. As far as that particular projector... its aspect ratio is 4:3 & its out of production now. Here is a projection throw distance calculator so that you can know how big your screen will be if you place it in certain places.

http://www.projectorcentral.com/Optoma-EzPro_739-projection-calculator-pro.htm

When it comes to throw distance... remember that the further away the screen is the more stretched the image will be (& thus dimmer). But also... NOT A PROBLEM, my screen is 120 inches diagonal, & its an awesome picture.

That lamp life will never last 5000 hours, haha, good luck reaching 4000 Happy I wouldn't worry about the lamp life though. My wife & I bought our system without an understanding of how cool it would be & how much we use it. We have no quam about buying a tiny little bulb every 2 years. (Or just use that occasion as an opportunity to upgrade Happy

If you are ever going to watch a lot of movies (or any other HD content), then I would suggest checking out a projector that handles 720p (which is widescreen). Right now, I would recommend the Sony VPL-HS51. You can find it brand new online for around $2500-$3000, just ask some projector sites for some quotes... & believe me, they will come streaming in (to your email). : )

If you are strictly using this for standard TV & for your computer (which you already run at 1024x768, then get the optoma.

If you want an decent online contact/salesmen, I will recommend Jason Tawse at projector center. [jason@projectorcenter.com] Thats who I bought from, he's quick & tells it like it is. Ask him any question Happy

Oh ya, projector center matches any online price or quote too, they are always lower than or equal to the lowest price.

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More questions
Sep 4, 2005 5:34AM PDT

Hi,

Thanks for the salesman contact. I'll e-mail him.

I already have a small screen; it is about 60" 4:3 and is on a stand. I figured I would use it most of the time, but then use a bigger screen for special events. What technology does your projector use? CRT, DLP, or LCD? How close do you sit to your 120" screen? What is the model number of your projector? I would like to read more about its specs.

I have seen projectors with lower lumens that say can project a larger max picture than a projector with higher lumens. How is that possible?

You said you replace your lamp every 2 years. How many hours a day do you use it?

You said I need a projector with 720p for movies & HDTV. DVD has a resolution of 720 by 480, so wouldn't even a projector with 800 by 600 SVGA resolution handle DVDs as good as possible?

720p HDTV is 1280 by 720. On a screen with 1024 by 768, it has more than enough vertical resolution and 256 less horizontal pixels. So shouldn't 720p HDTV still look pretty good at XGA resolution?

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More questions
Sep 4, 2005 10:19AM PDT

There a lot of things to consider.
The first one is the room, to use a front screen projector you need to be able to control the room lighting!!! This is VERY important.
The projector should be permintely mounted!!! As shoud be the screen.
Here is another link to a good place to buy.
They have some tutorials in the tool bar that some time and read up. John

http://projectorpeople.com/

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Why does it need to be permanent?
Sep 4, 2005 12:30PM PDT

What is wrong with having the projector sit on a desk most of the time and then having a screen on a portable stand that you fold up and take somewhere else? I didn't think a DLP projector would be too hard to set up like a CRT with 3 lenses.

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ok...
Sep 4, 2005 2:58PM PDT

I see where you're headed... you'd like something you can move around & right now you are probably thinking you can take it to your buddies & hook it up for a LAN party or movies/video-games all night. I'd recommend against that "lifestyle", especially if you are going to pay 3 grand for this sucker. Projection components are sensitive to various levels of heat & humidity, & can be damaged if you are not EXTREMELY careful. I fixed mine in a ceiling mounted cabinet downstairs where its cool & dry.

Also, not all movies are 720x480, that is specifically why they make some projector screens 854x480. If that optoma receives a 720p signal, it will definitely scale it down to 80% of its original size & you'll have black bars on top/bottom that take up exactly 25% of the screen. How good your picture looks when non-native signals are sent to it depends on how good its video processors are, you'll just have to go & see for yourself. I like Faroudja, they are have really decent components. I think Samsung puts Faroudja scalers in some of their upconverting dvd players & InFocus has them in some projectors. I'd imagine their scaling is a little bit more sophistocated then simple static bi-linear interpolation.

About the brightness ratings, or any kind of ratings... don't trust any online site or even the companies themselves, EVERYBODY IS SUBJECTIVE & the almighty dollar controls the world. You'll just have to go see yourself. (most sites report on projectors & they sell certain brands too, so whattya know : )

I haven't replaced my bulb yet, I was just guessing. We use are system a fair amount, but we don't turn it on unless we will have it on for at least an hour.

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ok
Sep 6, 2005 1:14AM PDT

So if a projector is advertised as 'portable', that does not mean it is more durable than any other projector?

Is there way to tell if a dvd is 720 by 480 or 854 by 480? Would a full screen dvd be 720, and then a wide screen be 854?

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Another reason for a portable projector
Sep 6, 2005 10:51AM PDT

Another reason I'd like a projector to be portable is to rent it out. I've seen projectors rent for at least $175 a day.

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Another reason for a portable projector
Sep 7, 2005 2:20AM PDT

Sorry for the confusion, I though you were setting up a permanent home theater. To rent out?? OK go for it. John

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heh...
Sep 6, 2005 3:26PM PDT

Hey, sounds like you have a lot already thought out, I can only offer suggestions as to what you do with your equipment, don't let me rain on your parade Happy

As far as dvd resolution, its my understanding that all DVDs have 480 horizontal lines. This means that 4:3 aspect ratio dvds have 640 vertical lines. This also means that widescreen dvds (16:9 aspect ratio) have 854 vertical lines. Some DVDs claim to have a 1.85 : 1 aspect ratio, which would mean they have 888 vertical lines. The really crappy DVDs are the ones that actually have 4:3 aspect ratio, they just leave black bars on the bottom & top so that the image part of the frame has a "widescreen" ratio.

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I'm confused about DVDs
Sep 6, 2005 11:22PM PDT

I make my own dvds from home videos and they are all at one point 720 by 480 with a 4:3 picture. Viewing raw video in 720 by 480, the picture is stretched. After the video is burned on dvd, the aspect ratio is fine. I think this has to do with square pixels vs. non-square pixels in pc monitors and in TVs. I forget which one uses which kind of pixels.

I'm thinking that 480 is the vertical resolution, a 16:9 picture would need more pixels horizontal than a 4:3 picture.

Did you just say vertical when you meant horizontal?

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heh...
Sep 7, 2005 5:29AM PDT

you are saying that 480 is the vertical resolution (which isn't very clear), but if I can guess at what you mean, you are trying to say that if you count pixels from the top to the bottom, there are 480 of them. Thats the same as saying there are 480 horizontal lines from the bottom line to the top line. I was correct in what I said.

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480 is the vertical resolution
Sep 8, 2005 1:04AM PDT

Well the problem is that NTSC 525 interlaced lines video is only 320x240 pixels, or EGA graphics. Commodor 64 any one?
Some markting type came up with the idea of calling NTSC SD or 480i to make easer for salesmen to say.
This is an apples to oranges way of stating things.

When talking about picture quality in NTSC they use the term "lines of horizontal resolution" or LHR (that's a mouth full) and it referfs to how much picture detail can be seen on each of the 525 horizontal scan lines.
So VHS VCR will have around 240 LHR and a 3 chip studio camera will have 700 LHR. Have fun. John

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Umm.
Sep 11, 2005 12:09AM PDT

So NTSC is 525 LHR or 320x240.

DVD is 640x480. 1050 LHR?

VHS is 240 LHR. What would be the pixel resolution?

Should NTSC be considered 240i ?

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ok
Sep 15, 2005 1:38AM PDT

I don't think I understand the connection between LHR and pixel resolution. You told me VHS is 240 LHR, but I have read that the 'nearest approximation' of VHS resolution is 352x480.

So either that pixel measurement is wrong or your measurement of 320x240 for NTSC is wrong because I'm pretty sure VHS has lower resolution than NTSC broadcasts.

The reason I asked if NTSC should be considered 240i is because the resolution you gave doesn't match up. DVD would be 480i because its resolution is 640x480. So NTSC should be 240i if its resolution is 320x240.

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Apples and Oranges
Sep 15, 2005 3:12AM PDT

Or analog and digital!!!!
The digital naming convention doesn't work in analog!!!!!!!!!! Like tring to put a round peg in a square hole, it just doesn't fit.
When the commodor 64 came out it used a standard NTSC 525 interlaced horizontal scan line analog TV for the monitor. You could hook it to any standard TV the had a video input.
It was called EGA graphics and the resoultion was 320x240 in computer terms.

So again analog NTSC video is 525 interlaced horizontal SCAN lines.
Allwise, there are 525 interlaced horizontal SCAN lines.
The quality is determined by how much detail can be seen on each of the 525 horizontal lines. And this will vary a lot depending on the source.

And it was never stated the way pixel resoultion is in digital. It doesn't fit!!!!!
DVD is 640x480p, the small i or p at the end ONLY applies to digtal. Since analog 525 is ALLWISE interlaced.
Back before VHS no one ever heard of the term "lines of horizontal resoultion" outside of engineers.
The home video happned and the VHS-Beta wars started and decks were rate in LHR. Then people who wirte for magizines started wirting columes about this. But may of them were not engineers and didn't realy understand what they were writing about, sort of the blind leading the blind. After a while things got straghinted out.
Now we have even more with all the digital formats and thoes writers are stll out there doing it all over again. John

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Apples and Oranges
Sep 15, 2005 3:59AM PDT

Or analog and digital!!!!
The digital naming convention doesn't work in analog!!!!!!!!!! Like tring to put a round peg in a square hole, it just doesn't fit.
When the commodor 64 came out it used a standard NTSC 525 interlaced horizontal scan line analog TV for the monitor. You could hook it to any standard TV the had a video input.
It was called EGA graphics and the resoultion was 320x240 in computer terms.

So again analog NTSC video is 525 interlaced horizontal SCAN lines.
Allwise, there are 525 interlaced horizontal SCAN lines.
The quality is determined by how much detail can be seen on each of the 525 horizontal lines. And this will vary a lot depending on the source.

And it was never stated the way pixel resoultion is in digital. It doesn't fit!!!!!
DVD is 640x480p, the small i or p at the end ONLY applies to digtal. Since analog 525 is ALLWISE interlaced.
Back before VHS no one ever heard of the term "lines of horizontal resoultion" outside of engineers.
The home video happned and the VHS-Beta wars started and decks were rate in LHR. Then people who wirte for magizines started wirting columes about this. But may of them were not engineers and didn't realy understand what they were writing about, sort of the blind leading the blind. After a while things got straghinted out.
Now we have even more with all the digital formats and thoes writers are stll out there doing it all over again. John

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DVD's
Sep 7, 2005 2:14AM PDT

To clear up some things.
Fisrt DVDs are 640x480p pixel format(3x4), or ED TV.
What you see on the screen depends on what you are watching it on. Analog TV or a digtal TV.
The black bars are the result of putting a 16x9 format in to a 3x4 size, or putting a 3x4 format into a 16x9 format.
When you use the term "lines" this refers to analog NTSC 525 line TV. Analog TV is in lines! Digital TV is in pixels! This does cause a lot of confusion!!!
True all wide screen formats are not 16x9, but this is the most common format. John

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KEEP YOUR COMPUTOR, GAMES, ETC IN THE BEDROOM
Sep 9, 2005 8:03AM PDT

Your home theater system is designed for just that awsome hi.def. and 5.1 sound When you add your computor stuff you are going to have a nitemare of problems with cables, poor performance etc. So what happens when someone wants to watch t.v. and your playing vidio games which could cause burn in on your display. even your computor could do damage to your t.v.

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Poor performance?
Sep 10, 2005 12:59PM PDT

What do you mean by 'poor performance'? There wouldn't be many cables because the only source it would be hooked up to (most of the time) would be my computer. My computer has a dvd player, surround sound speakers, a tv tuner card, and of course it can play pc games.

It is also my understanding that DLP projectors do not suffer from burn-in.

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Just a word of encouragement:
Sep 10, 2005 11:15PM PDT

I've also been in the market for a projector for quite a few years, but don't know which to buy. I do hope you succeed. Please tell me when you choose what projector you want. Good Luck!
-Ibrahim

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