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Discussion Starter · #1 ·
One question, ALWAYS that bothered me.

In front projection CRT's we talk about hours.

But when it comes to RPTV's, we don't talk about hours?

Are RPTV CRT's more resilient or something?




Secnod question:


What advantages does FP have over a Mits RPTV that has 9 inch CRT's?
 

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Wrong forum.


At the main menu listing all forums, under this one, CRT Projectors, it says, "Front or rear mounted CRT projectors questions and answers. Note...Not Rear Projection all in one units."


THe forum you want is listed 5 more categories down. "RPTV" implies a built-in TV tuner, the projectors discussed in this area generally do not have one, not even my 67" Barco 801s Retro. Also, I believe pretty much all the units discussed here are commercial units, not consumer units, and I do not recall a consumer unit featuring an hour meter.


-Chris
 

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rear projectors use smaller high gain screens

so the projector is not run as hot

and and the tubes last longer


XANATOS
 

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As far as the RPTV vs. front projection differences:


1. RPTVs are so tiny (the biggest have a screen that's not even 6' wide) it's impossible to get a good theatrical sense of immersion in many domestic seating environments (seating > 9' from the screen) and multiple rows are out of the question.


2. RPTVs put a big box between your speakers which isn't good for acoustics, flat projection screens don't.


3. Projectors will usually sync to interesting signals like [email protected] for NTSC DVD playback with neither scaling artifacts nor inverse 3:2 pull-down judder. Consumer RPTVs will not.


4. Projectors give you a lot of latitude in screen shape. Based on how I move my chair, I think a 2.35:1 screen with a first row @ 1.2-1.3 screen widths would be ideal.
 

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Discussion Starter · #5 ·
I posted it here, because it relates to FP, and the people in the RPTV,

lets just say there are not as knowledgeable:)


So basically RPTV tubes last longer than FP tubes, thus hours need not be discussed? Isn't this a huge advantage for RPTV?


As for RPTV's being "so tiny," I guess this is relative. But I will tell you that a 73"mits is HUGE, atleast for me. And it has 9" crts.

I have a 55" and I am impressed how big it is, every time I see it, even though I had since Dec. 2000.


Besides the acoustics, and scaling stuff, please tell me why I should go FP?

Convince me to go FP rather than 73" mits.
 

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How about 27" addtional inches and a few extra grand left in your pocket? Assuming an excellent condition 8" CRT FP.
 

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ps24eva


i used a barco 808 with a 100 inch 4x3 13 gain curved

made by vutec i put over 7000 hours on the tubes

with out any burn or wear and the picture

was as bright as my 36 inch tube set

i now use a 10 foot 4x3 curved screen

with a sony 1292 and i expect to get the

same long life results


XANATOS
 

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PS24EVA


IT IS NOT OR JOB TO CONVINCE YOU TO BUY ANYTHING

IF YOU LIKE THE MITS BUY IT


IF YOU WANT THE BEST

READ THIS FORUM AND LEARN ABOUT CRT PROJECTORS AND SCREENS

AND THEN BUY WHAT YOU WANT



XANATOS
 

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Quote:
Originally posted by ps24eva



Besides the acoustics, and scaling stuff, please tell me why I should go FP?

Convince me to go FP rather than 73" mits.
I agree with Xanatos but I'll answer anyway.


Why?


1.) My XG110 was probably about 1/3 the cost of the 73" Mits.

2.) My 100" diagonal screen is 1/3 bigger.

3.) The lenses in a CRT FP are must better than a RPTV so even though the Mits uses 9" CRT's the picture from a high end 8" or 9" CRT FP will be better.

4.) My XG110 will accept almost any resolution I feed it. Will your Mits?


Oh, and did I mention it was 1/3 the cost:D
 

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Discussion Starter · #10 ·
Ok some comments:

the comments regarding res are a non-issue. I am going to build a HTPC, and thus any res will be at my disposal. Size is a non-issue. Acousitcs is a non-issue. (getting RPTV recessed)

The only comment that interests me is the one made about the FP CRT's being better than Mits. Just for clarification, I already have a mits, am very knowledgeable about FP (not a newbie, but I also never had a FP either), but just wondering to buy another mits or go for FP. If someone can prove that FP's have better CRT's than the 9" inch CRT in a mits, that would be great. That is, can someone definitely say a FP will have better quality. Also the cost issue is intriguing. 1/3 as much? But don't you have to replace/rebuild your tubes? Isn't that money right there?


Secondly, I get the impression that people are not really sure about why no one talks about RPTV hours. yes, someone said the CRt's are being less stressed, thus last longer. But lasting longer still means they have a lifetime. Thus I am still confused nobody talks about RPTV hours.
 

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73" is huge compared to the TVs in people's living rooms, although that's the wrong comparison to make. You want to compare it to how big a cinema screen would be if you scaled it down to match the seating distances in your home theater.

Quote:
Originally posted by GScott


2.) My 100" diagonal screen is 1/3 bigger.
That 73" diagonal screen covers 2277 square inches. A 100" diagonal screen measures 4263 square inches. 4263/2277 = 1.87. Our small 100" diagonal screens are 187% the size of tiny 73" screens. A modest 110" diagonal (8' wide screen) covers 5184 square inches - 228% the area of the 73" RPTV. Big screens are in the 9-10'+ width range, have diagonals 124"-137" and beyond when in 16:9 format, and areas at least 289-352% of the 73" RPTVs.


Of course, this is only interesting for bragging rights, because immersion is determined by subtended angles and not absolute size. A 73" screen is 64" wide. To sit in your front row and have the same sort of image scale you get in the last row of a THX theater that meets their recomended 36 degree minimum subtended angle suggestion, it must be no more than 99" from the screen (IOW, 8'). If you don't sit in the back row when you go out for a movie, you'll want to sit closer - perhaps at the 1.2-1.3 screen widths that work well for good transfers of scope movies. In that case, you'd need to set within 77" of the screen (as in under 6.5').


To have the same field of vision filled that you do sitting 99" from that 73" diagonal screen, 100" lets you back up to 136", and 110" allows for a 149" seating distance. Likewise, given a good scope transfer that would have you sitting just 77" from the 73" screen you can move back to 105" with a 100" screen, and 116" with a 110" screen.


The bigger screens keep you from sitting silly close, and allow for multiple rows of seating where the front row is not close enough for compression/projection artifacts to be objectaionable and the back row is not far enough back to loose the sense of immersion.
 

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Quote:
Originally posted by ps24eva
If someone can prove that FP's have better CRT's than the 9" inch CRT in a mits, that would be great. That is, can someone definitely say a FP will have better quality.
Someone previously mentioned the lenses. Assuming the 9" tubes are the same as a FP it will depend on how the light gets transmitted. Kind of like having two exact camera bodies but using different quality lenses say Carl Ziess and Vivitar. I'm sure the Ziess lenes will yield a better picture. You are unlikely to find HD8 lenses on a RPTV.


Generally speaking the FPs will scan at a higher rate.


Also the viewing angles (top to bottom and side to side) will be broader than a RPTV. More people can see the screen / picture.


More tweakability on mechanical and electronic adjustments on a FP like centre / out focus, schlemplug etc


As for quality try a test DVD like Avia or Video Essentials and put some test patterns up and see for yourself.


As for the tube hours - good question. 10k hour is nothing to sneeze at on FP. I do have a few friends with RPTV and the ones who had problems with them it was not the tube wear but instead other things like power supplies dying etc.
 

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Quote:
Originally posted by ps24eva
Ok some comments:

the comments regarding res are a non-issue. I am going to build a HTPC, and thus any res will be at my disposal.
Sorry - I'm not an RPTV owner but I did wonder if this assumption is correct. From the little I've read about RPTVs they have a number of set resolutions that you have to be able to match with the output from your source (whether an STB or an HTPC), whereas with a CRT FP PJ you can pretty much throw any resolution at all at it (certainly that's the case for the 9-inchers).


Could someone please clarify this for me - am I right or wrong?


Andy.
 

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Andy, I think you are right, using HTPC for RPTV is perhaps a waste of computing power. I have never heard of any RPTV that can sync to multiple res's. I believe they may take different input res's, but the pj's output is one res...So why bother with HTPC? It's going to be scaled by the TV anyway.
 

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One of the MAJOR factors that I like about the FP and not the RPTV is that if you spend x amount of money on the RPTV it is only going to be one size and one size only. If for what ever reason you have to move or want to change a screen size for what ever reason you can only do that with the front projector weather its a CRT DLP OR LCD, so that point is valid for all those projection formats.


The other is, it/they dont take up any floor space generally speaking but your recessing yours. What if I dont have a place to reses mine and I want a 73" screen, I have to live with the huge wooden box in my living room.


Id rather have the unit flying over head and not smack in the middle of the room.


The immersion has already been discussed so I wont go into that any more as I have never watched a movie on a RPTV and had the feeling of being in a theater.


On a simpler note, I think front projection is just a high tech thing that not everyone has. You have to know what your doing to get it all looking and sounding good. Any one could go to Best Buy and buy a Big Screen TV and say they have a Home Theater.


The way I see it, you dont have a home theater unless you have at least a 90" screen. Everything else is just a Surround Sound System. There’s nothing wrong with that I just think the term Home Theater is used too widely. I went to a friend’s new home shortly after they got married and they gave my wife and me the tour of the home. The last room they showed us was the "home Theater" I walked in to this perfect room and was disappointed by the 65" RPTV. The room would make a killer theater with a 120" screen and front projector. Instead I saw their surround sound system.


One of the points is that if you have a front projection system your probably going to have a bunch of people over to watch movies and you cannot get all the people to say that they were able to see very well with a RPTV.


The other thing is that RPTV's have some distortion due to the mirror. I dont care what anyone says there is a loss in quality and dimension because of the mirror reflections. The idea with FP is a direct path of light with nothing to change the pattern or direction to get a true image every time. I feel you just dont get that with rear set ups unless they are done with a front projector set up in an enclosure with NO mirror to change the lights direction.


I may be wrong but thats just how I feel about it.
 

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"If someone can prove that FP's have better CRT's than the 9" inch CRT in a mits, that would be great. That is, can someone definitely say a FP will have better quality. "



The cheap lenses used in most RPTV is just the start...


My opinion is that even beyond the CRT lenses, the Fresnel screen system used in most RPTVs will reduce the maximum resolution to below that which the CRTs are capable of. IE, even if the tubes can resolve XXX, the screen can only do YYY, so you never get the full benefit of what the CRT can do...


--Kieth
 

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Quote:
Originally posted by VR Audio Systems
..........The way I see it, you dont have a home theater unless you have at least a 90" screen. Everything else is just a Surround Sound System. There’s nothing wrong with that I just think the term Home Theater is used too widely........ I may be wrong but thats just how I feel about it.
Vic, this is a bit off the topic thread but I agree 100%. I will even plagarize Russ Herschelman's (sp?) thoughts. If the room is not 100% light controlled and designed and used ONLY for movies then it is a multifunction media room and not a home theatre.
 

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BTW, when people talk about hours... 7000-10000 hours at something like 4 hours a day equals 5-7 years. I'd say that about equals the total lifetime of most RPTVs. At that point you'd retube for say $1000 and throw away the RPTV. I've heard that the chassis of a FP will last well over 30,000 hours.
 

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You can access the run time (crt hours) on most RPTVs but few know how to do it and even fewer can be bothered. You need to access it via the service menu.


IMO the hours on a RPTV are just as critical as on a Front Projector. The technology is basically the same.


Psychologically though, it seems that when you put a CRT projector in a box and make it a RPTV people tend to forget about the hours.


I know, I have both a RPTV (53") and a Front Projection system. I do tend to try and not have the RPTV on unnecessarily when I'm not watching it and keep the brightness and contrast levels lower to conserve the CRT life. But I'm probably not your average Joe. Most owners wouldn't give it a second thought.


I think that the average RPTV owner has little conception of how they work and just treat it like a normal television. (Unless you own both a RPTV and a Front Projector that is).


The main advantage of RPTV is that you can watch it in broad daylight and they tend to be brighter because of the smaller screen and distance to screen. IMO the type of screen employed on most RPTV restricts the image quality produced and you can produce a larger superior image on a front projector, but there are trade offs.


Your average front projector enthusiast (myself included) can get unnecessarily hung up on CRT run hours.


As to the so called "immersive experience" of a larger screen, I'm about to commit heresy here.


IMO you can be just as immersed in a movie with a RPTV.


The sense of enjoyment in watching a movie relates to IMO (in order of importance), quality of story and acting, sound and then screen size.


After all, I have enjoyed many movies on a small screen and when you go to the movies you are often seated further back in relation to the screen than you would be watching it at home and with heads in front of you and many distractions. Hardly an immersive experience.


About the only truly "immersive" experience I've had was when watching an Omnimax movie where the screen occupied a full 180 degrees of your field of vision and you could not be distracted by anything else.


Just my .02c worth :)


Mark
 

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the best projector in a rear projector

cost under 4,000 to manufacture

good front crt projectors

cost around 10-25,000

to build

also due to the dark protective

screen you lose way to much

shadow detail


again i am not trying to

convince you to buy anything


h*ell i don't even know what a mits 70 inch

hd set cost now

but i have seen them and was not impressed


if you still want a rear projector

for the convenience save yourself

some money and buy a big rca

rear projection tv


XANATOS
 
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