Torus 'Lite' with less extreme curves a success - AVS Forum
Forum Jump: 
Closed Thread
 
Thread Tools
post #1 of 158 Old 05-21-2005, 07:18 AM - Thread Starter
Advanced Member
 
Vince_B's Avatar
 
Join Date: Aug 2001
Location: Savannah, GA, USA
Posts: 686
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
My first attempt at a torus was less than successful, not the screen itself but I found that I was unhappy with the convergence and focus issues, and couldn't get enough bow from my G70 to compensate (some units have this quirk while others don't - your bow needs to start around 128 or so to have enough downward bow for the traditional curves commonly quoted). While I loved the look of the picture, the convergence and a few other issues were deal-killers.

The screen is ~ 88x48, the first attempt had curves on the horizontal edges about 7" deep, and about 2.5" deep on the vertical edges. The bow problem I've already mentioned, but the focus was impossible, the G70 just can't hack such a difference between center and edges very well. Since my screen is 'surface mounted' and protrudes off the wall, it protruded alot, about 11" total at the corners. Also I used one 80mm fan in a fanbox, and while it wasn't very loud, the rpm was fairly high and the noise it did make was fairly objectionable when the system was off (we walk through the den constantly and it just got on my nerves). Also I hoped to quiet the pj in the future so at that point I couldn't see how I'd get the fan to shut up when I did get the pj quiet. Lastly (this is still an issue and I'm surprised nobody has mentioned it) the curved screen has an annoying quality of echoing back at you when you talk in the room, esp from the sweet spot. I don't think this has too much effect on the audio but it must have an effect (I'm curious other's views on this).

So, I was one unhappy camper after spending $300 and alot of sweat. Finally I parked the screen in the garage and almost offered it to anyone fool enough to come get it. Well after getting tired of the flat pearlbrite I decided it would be a good experiment to cut gentler curves in the edges and try again. I figured it would help all the convergence issues and also require less suck power from the fan so I could use some really quiet fans. I have used the Silencer fan for years for pc projects and it's very quiet and reliable, the down side being low cfm and static pressure ratings. I decided to put in two silencers and not use fan boxes but instead something very simple and quick. I framed a little box in the two bottom corners 1/2" bigger than the fan and cut a hole to the outside so the fans can just pump air out. Quiet will come from the fact that the silencer is very quiet and besides most of the noise is airflow and the fanbox may just make it worse. I made the most direct clean air path I could. Here's one of the fanboxes (there is one in each bottom corner) from the inside showing the fan 'mounting' and wiring. The fan just nestles in the open-cell foam so there is no coupling between fan and frame.

http://homeyb.no-ip.com/images/torus...ite_fanbox.jpg

Here's a shot of the outside once mounted that gives a better idea of the whole thing.

http://homeyb.no-ip.com/images/torus...ox_outside.jpg

The two fans are not quite enough to totally pull the curve, after two days they have sucked the screen down 1.375 of the 1.75 dish. I don't see a problem here though, the center is the brightest anyway so it really doesn't stick out. To me quiet is the more important concern. The two fans have a much lower tone, and are barely audible from the seats in a quiet room.

The new screen box is much less dished, as I mentioned. The corners stick out 6.325" from the wall. The curve on the horizontal side is 3.5" deep, giving a low point on that edge that is 2.875" from the wall. The vertical edge dips 1.75" to a low point of 4.625" from the wall. These are much gentler curves than my last, approximately half the curvature, a little more than half on the vertical edges since I had less problems from that curve than the horizontal edges.

And of course the gratuitous screen shots, actually you can see the falloff in brightness toward the right edge (as always more evident in pictures but still present), it's really much better than the flat screen, no comparison actually.

http://homeyb.no-ip.com/images/torus...shot_front.jpg

And one where the curve is evident just for fun.

http://homeyb.no-ip.com/images/torus...nshot_side.jpg

I'm very pleased that I picked this project up again, the result is outstanding and I think a viable option that lessens some of the convergence issues. Also I think it's going to be much easier to come up with masking for this less-curved situation. So now I just need to finish the hushbox, mask the screen, build new speakers...
Vince_B is offline  
Sponsored Links
Advertisement
 
post #2 of 158 Old 05-21-2005, 07:50 AM
AVS Club Gold
 
Clarence's Avatar
 
Join Date: Oct 2003
Location: Northern Virginia Projector: G90 CRT
Posts: 8,850
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 12
Quote:
And one where the curve is evident just for fun.
Yes, those evident curves are very fun ;) :D

Nice job.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Clarence is offline  
post #3 of 158 Old 05-21-2005, 08:01 AM - Thread Starter
Advanced Member
 
Vince_B's Avatar
 
Join Date: Aug 2001
Location: Savannah, GA, USA
Posts: 686
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Thanks Clarence, wow to your theater, looking great!

Yes, I think Salma will be featured in more screenshots from now on.
Vince_B is offline  
post #4 of 158 Old 05-21-2005, 08:02 AM
AVS Special Member
 
overclkr's Avatar
 
Join Date: Jul 2003
Location: Chicago
Posts: 7,884
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Liked: 12
Very nice....

Cliff
overclkr is offline  
post #5 of 158 Old 05-21-2005, 12:01 PM
Senior Member
 
davidcrowe's Avatar
 
Join Date: Sep 2004
Location: Amherst, MA
Posts: 446
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
good idea. nice screen shot.
davidcrowe is offline  
post #6 of 158 Old 05-21-2005, 01:05 PM
AVS Special Member
 
MC Maniac's Avatar
 
Join Date: Jul 2001
Location: Southern Ontario
Posts: 1,827
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Congrats on sticking with it and making it work for you..

My fan is noisy too and I want to try others that may be quieter - I have the fan on a plug that has a 5 step voltage - you can lower the fan speed to quiet it down though, but I want the screen pulled all the way back..

What is your screen size?

What are you running your contrast at?

John
MC Maniac is offline  
post #7 of 158 Old 05-21-2005, 01:47 PM - Thread Starter
Advanced Member
 
Vince_B's Avatar
 
Join Date: Aug 2001
Location: Savannah, GA, USA
Posts: 686
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Screen is approx 88x48, contrast/bright at 50. You would likely find that the screen doesn't have to be pulled all the way back. Worth experimenting with, anyway.
Vince_B is offline  
post #8 of 158 Old 05-21-2005, 01:58 PM
AVS Special Member
 
MC Maniac's Avatar
 
Join Date: Jul 2001
Location: Southern Ontario
Posts: 1,827
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally posted by Vince_B
Screen is approx 88x48, contrast/bright at 50. You would likely find that the screen doesn't have to be pulled all the way back. Worth experimenting with, anyway.
Yeah I have experimented with the various fan speeds and lowering the speed hasn't affected the overall performance..

Your experience, that you can still get good results with a reduced curve depth, should encourage those with no seperate corner focus adjustments or limited bow range CRT's to go ahead and make one..

John
MC Maniac is offline  
post #9 of 158 Old 05-21-2005, 02:23 PM - Thread Starter
Advanced Member
 
Vince_B's Avatar
 
Join Date: Aug 2001
Location: Savannah, GA, USA
Posts: 686
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
When I realized that the lenses on the pj are designed for a flat screen, or for the factory curved screens (which seem to be very gently curved), it made sense to use a larger radius curve - if you want the tightest focus on any pj, even ones with corner focus. I still need to refocus the pj but it's not as far out as it was with the deeper curve.

One interesting thing is that the geometry irregularities of the pj are alot less conspicuous on the curved screen. I like that because I'm sensitive to the gullwing, pincushion, etc and it's just not apparent on the torus.
Vince_B is offline  
post #10 of 158 Old 05-21-2005, 03:02 PM
AVS Special Member
 
techman707's Avatar
 
Join Date: Nov 2002
Location: Florida & New York
Posts: 9,348
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 20
Hey Vince,

Are you using the Vutec "Pearlbright" on this screen also? How was the color shift when you were using the Pearlbright on the flat screen?

Bruce

P.S. When you setup the lens focus, did you reset the focus zones MG ALL, AQP and DQP to 128 BEFORE you attempted to focus the lenses? The HD-18 lens can be a real pain to get properly balanced between the center and sides right. If it's not right, ALL the focus can suffer.

"The greatness of a nation and its moral progress can be judged by the way its animals are treated." -Ghandi
techman707 is offline  
post #11 of 158 Old 05-21-2005, 03:37 PM
AVS Special Member
 
pcCinema's Avatar
 
Join Date: May 2002
Location: Portland, Oregon
Posts: 4,982
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Do away with the twin 80mm fans and use one 120mm running less than full speed. Much quieter than two "quiet" 80's.

Troy

The Non-Profit Home Theater Company will make your HTPC experience much easier.

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
pcCinema is offline  
post #12 of 158 Old 05-21-2005, 03:52 PM
AVS Special Member
 
stefuel's Avatar
 
Join Date: Apr 2001
Location: Marshfield, MA, USA
Posts: 5,883
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked: 13
Quote:
Originally posted by Clarence
Yes, those evident curves are very fun ;) :D

Nice job.
I've always been a fan of Salma's curves. Anyone seen her dance in "From Dusk till Dawn"? Damn if she don't fill out a two piece nicely?:D

Chip

Current owner of the last/best AmPro on the planet. The mighty 4600HD, and it's still running...better than Barco's, especially southern ones.
stefuel is offline  
post #13 of 158 Old 05-21-2005, 04:28 PM
AVS Special Member
 
techman707's Avatar
 
Join Date: Nov 2002
Location: Florida & New York
Posts: 9,348
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 20
Quote:
Originally posted by stefuel
I've always been a fan of Salma's curves. Anyone seen her dance in "From Dusk till Dawn"? Damn if she don't fill out a two piece nicely?:D

Chip
Easy there Chip!:D

"The greatness of a nation and its moral progress can be judged by the way its animals are treated." -Ghandi
techman707 is offline  
post #14 of 158 Old 05-21-2005, 04:52 PM - Thread Starter
Advanced Member
 
Vince_B's Avatar
 
Join Date: Aug 2001
Location: Savannah, GA, USA
Posts: 686
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Are you using the Vutec "Pearlbright" on this screen also? How was the color shift when you were using the Pearlbright on the flat screen?
Yes it's the same fabric. It was pretty bad flat, as was hotspotting (or as I've come to think of it the falloff of brightness away from the center - just a loss of light at the edges and the resulting poor CR)

Quote:
Do away with the twin 80mm fans and use one 120mm running less than full speed. Much quieter than two "quiet" 80's
Yeah, if I had a quiet 120 I probably would have tried that, this was all to prove out the 'lite' torus idea. I may order a couple of 120s and try them, the silencer is very quiet (have you used them?) and the small fan helps not protrude into the screen area any more than necessary, which in turn helps the fabric not come into contact with the corner of the fan mount when the fabric sucks down. I need one to stick in there and go 'hmm, looks like it will work.'

In reference to focus, this is killing me 'cuz about a month ago I did a tight focus on the flat screen, several hours worth. 'twas looking good, now very fuzzy in the center especially.

As to Salma, I forgot she was in Dusk til Dawn, but she's great in Desperado also, love the scene where the car accident happens due to driver distraction, just classic. Reminds me I need to rip that to my clips collection.
Vince_B is offline  
post #15 of 158 Old 05-21-2005, 05:17 PM
AVS Special Member
 
pcCinema's Avatar
 
Join Date: May 2002
Location: Portland, Oregon
Posts: 4,982
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Yes I've used the silencer fans, but any good (non quiet normal ) 120mm will beat it at less than full speed. Plain physics.
120mm won't add depth over 80mm.

Troy

The Non-Profit Home Theater Company will make your HTPC experience much easier.

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
pcCinema is offline  
post #16 of 158 Old 05-21-2005, 05:23 PM
AVS Special Member
 
techman707's Avatar
 
Join Date: Nov 2002
Location: Florida & New York
Posts: 9,348
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 20
Quote:
Originally posted by Vince_B
Yes it's the same fabric. It was pretty bad flat, as was hotspotting (or as I've come to think of it the falloff of brightness away from the center - just a loss of light at the edges and the resulting poor CR)



Vince,

The dark sides comes from running with too large a raster, but what makes me crazy from high gain flat screens is "color shift", where when you get a scene that's supposed to look like B&W, the color temp shift to 2 or 3 different temps accross the screen.

Bruce

"The greatness of a nation and its moral progress can be judged by the way its animals are treated." -Ghandi
techman707 is offline  
post #17 of 158 Old 05-21-2005, 05:54 PM
Member
 
lukewarm's Avatar
 
Join Date: Apr 2005
Posts: 176
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
In all the reading I've done about torus screens, I am still not sure what the advantages are supposed to be?
lukewarm is offline  
post #18 of 158 Old 05-21-2005, 08:12 PM - Thread Starter
Advanced Member
 
Vince_B's Avatar
 
Join Date: Aug 2001
Location: Savannah, GA, USA
Posts: 686
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
The dark sides comes from running with too large a raster, but what makes me crazy from high gain flat screens is "color shift", where when you get a scene that's supposed to look like B&W, the color temp shift to 2 or 3 different temps accross the screen.
The color shift is wicked bad with pearlbrite on a flat screen. That said it's only really an issue on bright scenes, but it is really, really noticeable. That and the hotspotting drove me to work on this again.

Quote:
In all the reading I've done about torus screens, I am still not sure what the advantages are supposed to be?
Torus screens address the issues we're talking about above, hotspotting and colorshift. For a really good idea of what these problems look like look at this great thread where they posted simulations of the various flat and curved screens with low and high gain and the issues that each displays. Take a look and I think it'll make sense.
Vince_B is offline  
post #19 of 158 Old 05-21-2005, 08:42 PM
Advanced Member
 
armstrr's Avatar
 
Join Date: Aug 2003
Location: sarnia, ontario, Canuckland
Posts: 693
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Liked: 18
yes, i too have noticed how the screen also focuses sound to the sweet spot...i'm getting used to it...its really only evident when you are talking with someone while facing forward...you sound as though you're yelling at them.
armstrr is offline  
post #20 of 158 Old 05-22-2005, 12:08 PM
Senior Member
 
davidcrowe's Avatar
 
Join Date: Sep 2004
Location: Amherst, MA
Posts: 446
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
I'm just waiting for the kids to discover this. Ok, I'm hoping they don't discover it.
davidcrowe is offline  
post #21 of 158 Old 05-22-2005, 01:22 PM
AVS Special Member
 
techman707's Avatar
 
Join Date: Nov 2002
Location: Florida & New York
Posts: 9,348
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 20
Quote:
Originally Posted by Vince_B
The color shift is wicked bad with pearlbrite on a flat screen. That said it's only really an issue on bright scenes, but it is really, really noticeable. That and the hotspotting drove me to work on this again.

What I can't deal with is when you see a terrible color shift running down the center of the screen on B&W material. Is the Torus you're now using able to make the entire screen the "hot spot"?

"The greatness of a nation and its moral progress can be judged by the way its animals are treated." -Ghandi
techman707 is offline  
post #22 of 158 Old 05-22-2005, 04:55 PM - Thread Starter
Advanced Member
 
Vince_B's Avatar
 
Join Date: Aug 2001
Location: Savannah, GA, USA
Posts: 686
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
here's a black and white image, only thing I could come up with...

http://homeyb.no-ip.com/images/torus...britney_bw.jpg

here's a full white image, as usual colorshift is more evident on the camera, actually much more, if I had time I'd color correct it to look more like what I'm seeing. Actually that's quite heinous. I don't know if my eyes are compensating or if the camera is exagerating it, but at any rate it looks really bad here but nothing, and I mean nothing like the flat. I no longer notice it when watching a movie, I would have to really scrutinize the frame to pick up on it. Interesting.

http://homeyb.no-ip.com/images/torus...full_white.jpg

here's another shot so you can evaluate the geometric distortion of the curves, wink, nudge.

http://homeyb.no-ip.com/images/torus...salma_desp.jpg
Vince_B is offline  
post #23 of 158 Old 05-22-2005, 08:25 PM
AVS Special Member
 
Ericglo's Avatar
 
Join Date: Oct 2004
Location: Just below the US in South Florida
Posts: 6,272
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 99 Post(s)
Liked: 43
This is great work Vince. One of the big issues has been what is the minimum curve needed to get good results. I really like your angle shot. If that is what your actually seeing, then I guess Torus screens do have a good viewing angle.

Ericglo

Call AVS For the Best Deals!!!


My new favorite game is Stop the Bots
Ericglo is offline  
post #24 of 158 Old 05-22-2005, 10:43 PM - Thread Starter
Advanced Member
 
Vince_B's Avatar
 
Join Date: Aug 2001
Location: Savannah, GA, USA
Posts: 686
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Thanks, I'm loving the screen. That screenshot is untouched except to size it, and the relative brightness should compare directly with the straight on shots (room conditions etc exactly the same). I would say this is the minimum curves to get some of the benefit of the torus without sacrificing too much in the way of focus or geometry.

There have been several threads where it has been pointed out that off-angle is not a problem for torus screens. One thing is that the vertical curve is helping regardless of where you are in the room. Even with the first torus, I watched from the couch on a side wall as I was whooped after hanging it, and I remember commenting that it was the best projected image I'd ever seen, this was about 35 degrees off axis or maybe more. This is definitely a compromise situation where you can control which factors are most important to you - alot of products are made that way and you aren't the wiser, I think it is actually part of the fun to know the limitations and be able to see the flaws and the good points. The htpc people will understand this from the standpoint of dscaler etc. where it's not perfect and you can see it working it out but that's part of the fun, at least to me it is.
Vince_B is offline  
post #25 of 158 Old 05-23-2005, 05:22 AM
AVS Special Member
 
Semisentient's Avatar
 
Join Date: Sep 2003
Location: Woodbridge,Ontario
Posts: 1,417
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by Ericglo
I guess Torus screens do have a good viewing angle.

Ericglo
Yup. That's what me and MC Maniac have been saying all along!

There's no place I can be, since I found Serenity. You can't take the sky from me.
Semisentient is offline  
post #26 of 158 Old 05-31-2005, 08:54 PM - Thread Starter
Advanced Member
 
Vince_B's Avatar
 
Join Date: Aug 2001
Location: Savannah, GA, USA
Posts: 686
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
I had a request for more details on the construction so I kludged together a drawing that hopefully will help visualize the thing. It's not that bad to build and I would emphasize giving some thought to the fan situation and testing the noise of your proposed fan before going there and having to do it twice. I found that elaborate fanboxes were not very helpful but using more quieter fans helped alot. As mentioned above 120mm fans would likely be the best but if you use my fan mounting (very simple and quick) you'll need to watch that the fabric will not draw down and touch the corner of the fan mount that is nearest the center of the screen. I'm quite happy with what I've got but may pick up some big fans to try out the idea - the main noise is air movement like the projectors themselves, so I don't know how much better it can be got. Ok you're bored enough if you read this far....

http://homeyb.no-ip.com/images/torus...ed_drawing.jpg

let me know if there's still some confusion. One real important thing to remember is that when the fabric pulls down you have to keep it from hitting anything, so leave clearance.

Oh, just my $0.02... and I was guilty of this too before seeing it in action. Listen to the guys when they say not to worry about being real careful with the dimensions etc. If that stops you from doing a torus it would be a real shame, any torus or even a simple curved screen will be better than a flat one. Period. So, kludge up something and see for yourself how great it is. Also DON'T get hung up on the fan issue of whether to put a mechanical switch or to try to vary the speed. A simple 100 ohm *potentiometer* resistor in line with the fan will let you turn it up and down, but if you use the silencer fans you will need to run them full out and even then they won't pull the screen all the way. IT'S OK, remember you will be so happy with the result and you'll realize that it doesn't matter. You really DON'T need the curve totally deep in the center anyway, it's not your problem area, the edges are (remember the torus makes the edges behave more like the center - this is all about what happens AWAY from the center). If the screen never makes it that last 1/4" YOU WILL NOT BE ABLE TO TELL WITHOUT A RULER. Ok, enough, build a torus.
Vince_B is offline  
post #27 of 158 Old 05-31-2005, 09:23 PM
AVS Special Member
 
techman707's Avatar
 
Join Date: Nov 2002
Location: Florida & New York
Posts: 9,348
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 20
Vince,

It looks like you're really smokin now. I'm going to try one out when I feel strong enough to do it. I have a few special "Globe 120mm fans that I bought for PC assembly because they were rated as the one of the quietest 120mm fans made. From what I've heard, if you do too good a job, you will have TOO MUCH fan pull and might even have to reduce the fan size and speed. One guy posted that he had to actually drill holes in the frame to allow MORE air to reduce the pull.

How does HDTV look on the screen with the G70?

Bruce

"The greatness of a nation and its moral progress can be judged by the way its animals are treated." -Ghandi
techman707 is offline  
post #28 of 158 Old 05-31-2005, 09:44 PM - Thread Starter
Advanced Member
 
Vince_B's Avatar
 
Join Date: Aug 2001
Location: Savannah, GA, USA
Posts: 686
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
How does HDTV look on the screen with the G70?
it's fantastic - all we're getting right now is OTA, only nbc and cbs. Not to beef too much, CSI is on three nights a week :) . I'm really, really looking forward to hd-dvd. I guess 720p will be a standard and maybe 1080i, well since they're talking about a possible merger who knows but either one is really great on this setup. Thanks for the great pj!

Let me know if you need any input on the screen design, maybe I can help. It's not that bad if you steer clear of the really detailed (and unnecessary) obstacles and (let me borrow your method of emphasis again) KEEP IT SIMPLE. :D Oh, I forgot to mention above, plywood greatly, greatly reduces the weight of the beast, using 1/2" for the sides is adequate with glue and nails, maybe a couple of braces but doing the lite really doesn't need bracing.
Vince_B is offline  
post #29 of 158 Old 05-31-2005, 10:00 PM
AVS Special Member
 
techman707's Avatar
 
Join Date: Nov 2002
Location: Florida & New York
Posts: 9,348
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 20
Vince,

I get all the networks here in NY OTA and I'm using a Samsung SIR-TS360 box. While HD is fine overall, I'm not really happy with ANY "film material" in HD. It usually appears muddy to me. However, you should see "American Idol" on Fox. That is BY FAR, the BEST HDTV I have seen to date and that includes watching the studio monitors at the networks directly. To me, it PROVES that they're NOT transferring film correctly in HD. I've never used the newer Rank Flying Spot Scanners that do HD, but at some point, someone should wake up and open their eyes. It has NOTHING to do with CRT because I've tested it with digitals also and they're not really any better. I would sure like to see what a log Gey Scale looks like coming off the scanner, it can't possibly be right.

Bruce

"The greatness of a nation and its moral progress can be judged by the way its animals are treated." -Ghandi
techman707 is offline  
post #30 of 158 Old 05-31-2005, 10:06 PM
Advanced Member
 
madclammer's Avatar
 
Join Date: Mar 2003
Location: east
Posts: 715
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Hello. great reading.some questions if i may.You are trading focus for brightness is that right? or is it possible to have as good a focus with a torus ? Could the torus screen physics be aplied to a rearscreen set up? I pursued rear screens hoping to achieve greater brightnes through total light control with no loss of focus. Can someone here post diy plans for a fiberoptic rear screen that is 5x brighter than my gerriats and also increases focusing power by at least 3x. thanks.:)
madclammer is offline  
Closed Thread CRT Projectors

User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off