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Don't mean to reel you in Dabingles... but just before you run off on this based on what a pretty biased site says (you expected HTPCnews to give you a balanced story?).

For what you're doing, if I understand it right, you're building your own projector out of a 15" LCD monitor and planning to project it onto a home made screen. Chances are you probably want to use a PC based solution (besides everyone understands them, and it's the easiest way to get a source into a computer monitor, strangely enough)

This really sounds like a Slashdot (oops, /. ) type project. As for HD quality - what is HD quality? You will be sending a 1600x1200 signal to a monitor and beaming a light source through it. Yes, the signal will be a high resolution, but if even professional manufacturers can't get a good contrast ratio on their projectors, I'm not so sure yours will fair very well. You can put a checkmark beside "high res" on your list of cool features, but I'm not so sure how great the final product will be.

As for video off a DVD, that's easy to demystify. It's an NTSC signal. MPEG-2 compressed, 720x480 at D1 pixel aspect. To get that to a projector at some resolution other than standard D1, it has to be scaled. Whether a player, a computer or the projector itself scales the image, it's still scaled. So it's hard to know where this "HD resolution" would be coming from... I can scale an NTSC source up to 4,000,000x3,000,000 square pixels, at Sooper-Dooper HD res, and it's just going to get either softer or chunkier depending how it's scaled.

I understand the "cool" factor of building it yourself (I built my own arcade game cabinet) and that you want to be able to play games on a large scale and use it as a PVR (which again is pretty tough - hard to get drives that will sustain high data rates for entire shows), but in the end, you may be very disappointed with how things turn out.

Ultimately your decision, but it seems like more of a science project than a solution.

Bren R.

Here is a fellow AVS-er that has done numurous tests between his standard DVD player vs a properly configured HTPC. In his site he has a capture of the same media in a DVD player vs his HTPC.

http://www.myhometheater.homestead.com/HTPC.html

There are many more AVS-er that have done this comparison...including me and we got a better picture using a properly configure HTPC vs a standard DVD using the same projector. A lot of this comparisons can be clearly seen on projectors because we blow up the image to 80-120 inches. You won't see it in standard 20-43 inch TV. In this case size does matter.

HTPC
matching output resolution to projector giving a 1:1 mapping so no scaling occurs. This then uses the technology inherent in software DVD players where hardware technology (chips) and current algorithyms can present the best picture possible. The software is the scaler in this case. Software such as DSCALER, FFDShow and NVDVD are some names that produce these.


DVD player
today there are DVD players that are top notch with built in scalers such as Faroudja or Pixelworks. Players such as the Bravo D2 or the Panasonic RP82. Alas not all DVD players are created equal. Chances are that $50 DVD player you bought mother-inlaw does not have as great as a picture as a properly configured HTPC player or any of the DVD players above.

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This really sounds like a Slashdot (oops, /. ) type project. As for HD quality - what is HD quality? You will be sending a 1600x1200 signal to a monitor and beaming a light source through it. Yes, the signal will be a high resolution, but if even professional manufacturers can't get a good contrast ratio on their projectors, I'm not so sure yours will fair very well. You can put a checkmark beside "high res" on your list of cool features, but I'm not so sure how great the final product will be.

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Here is a primer on HTDV
http://www.physics.udel.edu/wwwusers/watson/student_projects/scen167/ateam/HDTV/

A few of us actually are ISF calibrate our sets. If not the Avia or Home Theater Essensial DVD can help calibrate your set or projector.

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I can scale an NTSC source up to 4,000,000x3,000,000 square pixels, at Sooper-Dooper HD res

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So you didn't notice a difference of quality of the same source coming out of your Sooper-Pooper than your mother-in-laws DVD player?

Get a great DVD player like a Denon 2910 or 1910 and use Apple Airport Express to wirelessly send your music to your receiver from your PC. Then just use your PC that you already own to surf the internet. You also should look into getting a real projector. I cannot beleive that a $700 DIY projector would look any good when you can get an Infocus or Sanyo for $1000-1500.

Projectors by Optoma, Infocus, Epson, Benq have street prices below $1000.

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Here is a fellow AVS-er that has done numurous tests between his standard DVD player vs a properly configured HTPC. In his site he has a capture of the same media in a DVD player vs his HTPC.

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So what we're looking at is some extra signal processing (unsharp masking) we used to do the same thing in film by shooting a blurred positive (slide) and two sharp negatives, you superimpose them on high contrast paper (like Kodak Polycontrast IV RC) - you get blurred fields of similar color (like subtle face tones), yet you get crisp edge detail. It's a great way of selectively blurring blotchy skin tones, etc - in video it works similarly, regaining lost edge detail without making the entire picture pixelated. That's great, and will a cheap projector do this? Maybe not. But for the extra cost of a HTPC, you could probably bump yourself up to a good projector and DVD-P with DVI or component connectivity.

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matching output resolution to projector giving a 1:1 mapping so no scaling occurs. This then uses the technology inherent in software DVD players where hardware technology (chips) and current algorithyms can present the best picture possible. The software is the scaler in this case. Software such as DSCALER, FFDShow and NVDVD are some names that produce these.

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It's misleading to say no scaling occurs. It occurs in the software signal processor. It's just been moved from whatever is inside the cheap projector to the PC processor. You're still blowing up a 720x480D1 signal to 1600x1200 (or whatever res your projector runs at) - you're just sending it a more contrasty image to make up for the inherent softening. You can't blame a DVD-P for outputting an NTSC signal just because you want to use it on something developed for computer output.

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today there are DVD players that are top notch with built in scalers such as Faroudja or Pixelworks. Players such as the Bravo D2 or the Panasonic RP82. Alas not all DVD players are created equal. Chances are that $50 DVD player you bought mother-inlaw does not have as great as a picture as a properly configured HTPC player or any of the DVD players above.

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Again, the Daytek player puts out an NTSC (television) signal. If someone is looking for a signal that isn't at a standard broadcast resolution, something in the chain better be good at scaling it, be it software, or hardware inside the projector. If the projector was worth it's salt, it would look just fine whether fed from a Mac G5 or a Koss My First DVD Player. The only thing that site you sent shows me is that the projector was a low-end consumer/business model that does a terrible job of upres'ing.

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Here is a primer on HTDV

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*laughs* Thanks for the primer. I work in broadcast.
There's no HDTV standard... 1080i? 720p? and I was asking more where he thought this Hi-Def signal was coming from... any DVD is just standard television resolution and worse, it's highly compressed MPEG-2 video.

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So you didn't notice a difference of quality of the same source coming out of your Sooper-Pooper than your mother-in-laws DVD player?

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You missed the point. No matter how much you scale up standard resolution off a DVD, you don't unlock hidden resolution on the disc, you interpolate the information that's already there. Any signal can be scaled to any size, but it's only as good as the original video stream.

Bren R.

Yeah I think buying a commercial projector might be the best and safest bet. I have just been reading at DIY audio and many people have gotten some really impressive results such as, this, or this or even this
The last one is probably the best one I have seen. The LCD I plan to use has a higher native resolution, response time and contrast ratio.

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Projectors by Optoma, Infocus, Epson, Benq have street prices below $1000.

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But are those projectors HD?

HOLY CRAP! Bren/Saturn.
When I get the money to upgrade my viewing capabilities, will one of you guys come down and help? I'm scared now.

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When I get the money to upgrade my viewing capabilities, will one of you guys come down and help? I'm scared now.

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It's really not that daunting a task... you just have to realize what the limitations of technology are, and right now is not the time to be buying displays (sad but true) - everyone's still got their hat in the ring on the HD standard... or non-standard - the letters HD mean nothing anymore - they're used in so many ways, they've lost all meaning... hell, the middle setting on an APS snapshot camera has now been renamed "HD" - it's wider than classic (1.5:1 ratio) prints. (actually, the neg is shot at "classic" it's just tagged to be cropped at print time to look wider - and gets grainy)

The HDTV debacle makes VHS vs Beta look like a fight over where to put the couch. And until a real standard gets pinched off by whoever has the strongest marketing campaign, I'll stick to my 4:3 27" tube TV. I am pulling for 1080i - I prefer an interlaced display. Of course, the skateboard video kids and music video producers for "ExTr33m Bl1nG" mook rock-rap bands you'll never hear of like shooting progressive to give their $1000 Panasonic handicams "film cred, yo!"

Geez, I've been taking my share of rants lately - there's so much marketing BS that gets swallowed that I feel like my head will explode every time I hear it.

Bren R.

I thought 1080P was the HD standard. Did I miss something?