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#### Technology3456

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1. How much curviture is good for 130 inch 2.35:1 screen at 14 feet viewing distance? For use primarily with:
• Double stacked projectors for passive 3D, using two Isco IIIL anamorphic lenses, projected onto a, approximately, 2.5 gain screen
• And sometimes for use with 2D from one projector and one Isco IIIL anamorphic lens.
In addition to the Isco IIIL lenses, the signal to the projectors will go through a geobox 602 which can curve or uncurve an image, as well as correct for pincushion and distortion and barrel distortion I believe, or leave it be if that's what you want for a curved screen. Whichever way it needs to go, I think it can go, if that informs what type of curve to use.

2. If I get a 130 inch diagonal 2.35:1 curved screen, is that now less than 130 inches because of the curve? Like if I set up the geobox to make a 130 inch diagonal curved image, will it be calculating 130 inches length along the curve of the screen, or calculating it horizontally in a straight line (which would then require less length than the curved image, if you see what I mean. You get somewhere faster in a straight line than a curved line because it's a shorter distance. Depending on the curvature, either it would make an image 130 inches measuring horizontally, and maybe 135 inches measuring along the curve, or it would make an image 130 inches measuring along the curve, and maybe 125 inches horizontally, and when I plan my setup, I do not know which way it will measure.

#### T-Bone

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1. How much curviture is good for 130 inch 2.35:1 screen at 14 feet viewing distance? For use primarily with:
• Double stacked projectors for passive 3D, using two Isco IIIL anamorphic lenses, projected onto a, approximately, 2.5 gain screen
• And sometimes for use with 2D from one projector and one Isco IIIL anamorphic lens.
In addition to the Isco IIIL lenses, the signal to the projectors will go through a geobox 602 which can curve or uncurve an image, as well as correct for pincushion and distortion and barrel distortion I believe, or leave it be if that's what you want for a curved screen. Whichever way it needs to go, I think it can go, if that informs what type of curve to use.

2. If I get a 130 inch diagonal 2.35:1 curved screen, is that now less than 130 inches because of the curve? Like if I set up the geobox to make a 130 inch diagonal curved image, will it be calculating 130 inches length along the curve of the screen, or calculating it horizontally in a straight line (which would then require less length than the curved image, if you see what I mean. You get somewhere faster in a straight line than a curved line because it's a shorter distance. Depending on the curvature, either it would make an image 130 inches measuring horizontally, and maybe 135 inches measuring along the curve, or it would make an image 130 inches measuring along the curve, and maybe 125 inches horizontally, and when I plan my setup, I do not know which way it will measure.
1. How much curvature is good? I don't think it really matters, does it? You're not building a screen are you? You are going to buy a curved screen that's pre-built. So you'll get the amount of "curvature" that is calculated into your pre-built screen. And your processor should be able to account for the screen curve.

2. If you take a Band-Aid that's 4 in Long and wrap it around the sides of a Coke can... Is the Band-Aid still 4 in long? It is. The linear length of your curved screen does not change.

Don't try to be smarter than the electronics. If you have electronics that can compensate for a curved screen, then let it compensate and don't worry about how it does it.

But if you're asking if you have a \$130 in diagonal curved screen, how wide is the screen when you put it on your wall, talking about the linear width, then you can get that from the spec sheet of the screen.

-T

#### Technology3456

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1. How much curvature is good? I don't think it really matters, does it? You're not building a screen are you? You are going to buy a curved screen that's pre-built. So you'll get the amount of "curvature" that is calculated into your pre-built screen. And your processor should be able to account for the screen curve.

2. If you take a Band-Aid that's 4 in Long and wrap it around the sides of a Coke can... Is the Band-Aid still 4 in long? It is. The linear length of your curved screen does not change.

Don't try to be smarter than the electronics. If you have electronics that can compensate for a curved screen, then let it compensate and don't worry about how it does it.

But if you're asking if you have a \$130 in diagonal curved screen, how wide is the screen when you put it on your wall, talking about the linear width, then you can get that from the spec sheet of the screen.

-T
1. If I do a curved screen, yes I may have control over the curvature. I think if anyone still sells a pre-made curved screen, they may also have different curvature's available, but maybe not. Otherwise, any screen I get that isnt pulldown will have to flipped onto the ceiling, which means I may to build the frame with hardware store stuff. Someone is helping me and they said they think they can design it so I just need to buy the stuff and put it together basically.

Obviously I am not qualified to be able to create anything like this. It will come down 100% to the person helping me, whether they can make a design and find the parts or not. They are being super generous helping me and I appreciate that.

2. That's true but I am asking the other way around. If the coke can is 4 inches around, and 2 inches around from one side to the other side, is it also just two inches to go straight through the sides of the can one side to the other side, no, it's shorter.

So if if I set the geobox for a 130 inch curved screen, is it measuring straight from one side of the curved screen to the other, or is measuring along the curve which would be longer?

#### brandonmack

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As far as I know, most manufacturers only offer screens with one curve radius, and the amount of curve is calibrated to compensate as best as possible for the anaglyph lens. The radius is also usually large enough that the difference in the screen size and the distance between the edges is pretty small. Anyway, they generally seem to be measured by the width of the screen itself, not the distance between the left and right edges.

#### Technology3456

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As far as I know, most manufacturers only offer screens with one curve radius, and the amount of curve is calibrated to compensate as best as possible for the anaglyph lens. The radius is also usually large enough that the difference in the screen size and the distance between the edges is pretty small. Anyway, they generally seem to be measured by the width of the screen itself, not the distance between the left and right edges.
It would be a small difference but Im going to have a pulldown 2D screen like 6 inches behind a flip down curved screen if I go with a curved screen. I have no wall to use and no one manufacturers pulldown curved screens that I know of, so this would be the only way.

Meaning, I dont just have to align two projectors to the curved screen, I have to have the exact calculation on the projector throw distance, curved screen size, and distance between the curved screen and the pulldown screen behind it, that my projectors are aligned to both screens perfectly at different distances. Otherwise I need to realign my projectors every time I watch on one screen or the other, or I need different projectors for each screen. So basically the curved screen 6 inches closer will have to be slightly smaller than the pulldown screen, but it has to be very exact.

As for the amount of curve, apparently different throw distances with different anamorphic lenses, create different amount of curvature. So the correct curve for my lenses and throw distance might be different than someone else's. That's why I was asking how to determine that. If manufacturers only making one type of curve, then I guess these things arent as important as I thought? Because what if their own curve doesnt fit your throw distance and anamorphic lens(es)?

#### T-Bone

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It would be a small difference but Im going to have a pulldown 2D screen like 6 inches behind a flip down curved screen if I go with a curved screen. I have no wall to use and no one manufacturers pulldown curved screens that I know of, so this would be the only way.

Meaning, I dont just have to align two projectors to the curved screen, I have to have the exact calculation on the projector throw distance, curved screen size, and distance between the curved screen and the pulldown screen behind it, that my projectors are aligned to both screens perfectly at different distances. Otherwise I need to realign my projectors every time I watch on one screen or the other, or I need different projectors for each screen. So basically the curved screen 6 inches closer will have to be slightly smaller than the pulldown screen, but it has to be very exact.

As for the amount of curve, apparently different throw distances with different anamorphic lenses, create different amount of curvature. So the correct curve for my lenses and throw distance might be different than someone else's. That's why I was asking how to determine that. If manufacturers only making one type of curve, then I guess these things arent as important as I thought? Because what if their own curve doesnt fit your throw distance and anamorphic lens(es)?
1. Okay, I think we have an issue. You see the bolded area in the quote? That has absolutely nothing to do with your original query. Your query was curved screen. Now you're saying well now you've got two screens and two throw distances and one of the screens is not curved. And you do this all the time. You just were admonished in another thread by another user when you asked a question... somebody gave you a reply... and then you came back with a whole bunch of other crap which was not what you originally asked. And you were called out for it.

2. So while I'm not an expert in the area, I am aware that if you use a curved screen without a anamorphic lens, then you may get some pincushion distortion. And using an anamorphic lens reduces the pin cushion caused by a curved screen.

But you also have the Geo box 602 you say. And that can process the image for a curved screen. How much can it compensate for? You probably need to reach out to the manufacturer or ask questions specifically about that geobox 602 model. To understand what it's capabilities. So I'm not really sure you even care about the curve if you have the 602 in the loop. That can compensate for any kind of pin Cushing or barreling that you say it can do. So I think you're wasting time with this question about the curvature of a screen.

3. So you say you've got two screens and everything has to be calibrated for the two screens. And there is a distance between the two screens of 6 inches according to what you're planning.

Why don't we pretend we're Einstein and perform a thought experiment. Let's imagine you have everything set up and you're watching a 3D movie with your setup on your curved screen... Anamorphic lenses in place, and your geo box 602 video processor.

Imagine we have no automation and we have to now change our system configuration to watch content on a flat 2D screen that is at a different distance than the curved screen. We'll do the steps manually. And then it's up to you to find automation to do it for you.

A. Either remove the Geo box 602 from the video path or configure it to not process the video image in any way so that it does not introduce pin Cushing or barrel distortion.

B. Adjust the zoom, lens shift if needed, and focus of the projectors.

C. (Optional step) Slide the anamorphic lenses out of the way.

So how do you go about automating those three steps? Step b is easy. You have saved memory settings in your projector for the focus lens shift and zoom so it's as easy as calling up a memory setting.

Step A should be just as easy. There's got to be some configuration to turn processing on and off via some remote control code.

I presume you want the anamorphic lenses in place for your 2D screen. I'm not sure if it's scope but I recall your other threads where you want to use the anamorphic lens all the time.

-T

fatherom

#### T-Bone

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Side thought:. Remember when me and other people told you you were making this way more complicated than it needed to be? You do know there are a bunch of people in AVS forum that have curved screens. And a bunch use anamorphic lenses. And they do it with a single screen and a single projector. What do they know that you don't know? That's what you ought to be asking yourself.

You should be asking yourself why there are so many people on AVS forum that decided to build their homes theaters with one projector and one screen. Imagine how Much they are missing out on with their simple configurations. Because they did it wrong. You know that you need two different screens and double stack projectors. You need to start a separate thread admonishing all of the users out there, including me, that shortsighted enough to use one projector and one screen. . Of course I'm joking but you get the point.

It's like you didn't really leverage any of the information that other users have. You said that you want 3d come hell or high water, and you are definitely going to use two projectors stacked and all of the issues that come with it, because you say so and what you want outweighs the experience and knowledge other uses on the board have. You don't even understand the history of why people double stack projectors in the first place. The main reason was during an era of dim projectors. So the double stacking was a solution to a problem that no longer exists. Although it exists in your case today. Keep reading and I'll tell you all about it.

You ended up buying projectors that are way too dim. Because you didn't do the research and what you actually needed. Oh, I know you did some research because you have the posts to prove it. But you didn't get the information that you needed. You insisted on telling everyone here that you were building your system all pieces at the same time because the interrelated. But when you try to build the system your way, things get dropped.

You are going to have a system not designed very well. You're going to have all sorts of problems between two different screens. But that's the way you want to do it.

If you leveraged the knowledge and experience of the other members, you could have had
• 4K HDR DLP projector 3D flat screen doing everything that you wanted it to do
• projector bright enough where you wouldn't need an anamorphic lens (although there is still a benefit for constant image height setups).
• No need for a curved screen.
• No need for double stack projectors.
• No need a high gain screen to compensate for your dim projectors.
• No need for a geo box 602 video processor.
• No need to spend \$1,500 to \$2,000 on madvr so you can tone map 4K HDR to work on your old technology projectors.

Your system is poorly designed and you have a whole bunch of Band-Aids to correct deficiencies that you introduced.

I could have set up a system for you in your room if you gave me diagrams in about a week, and that would have been me spending about 15 minutes a night looking at your problem for 7 days.

I don't have the best system, but it's nice. And I spent several hours last night in my game room watching 4K HDR content.

-T

fatherom

#### Technology3456

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1. Okay, I think we have an issue. You see the bolded area in the quote? That has absolutely nothing to do with your original query. Your query was curved screen. Now you're saying well now you've got two screens and two throw distances and one of the screens is not curved. And you do this all the time. You just were admonished in another thread by another user when you asked a question... somebody gave you a reply... and then you came back with a whole bunch of other crap which was not what you originally asked. And you were called out for it.

2. So while I'm not an expert in the area, I am aware that if you use a curved screen without a anamorphic lens, then you may get some pincushion distortion. And using an anamorphic lens reduces the pin cushion caused by a curved screen.

But you also have the Geo box 602 you say. And that can process the image for a curved screen. How much can it compensate for? You probably need to reach out to the manufacturer or ask questions specifically about that geobox 602 model. To understand what it's capabilities. So I'm not really sure you even care about the curve if you have the 602 in the loop. That can compensate for any kind of pin Cushing or barreling that you say it can do. So I think you're wasting time with this question about the curvature of a screen.

3. So you say you've got two screens and everything has to be calibrated for the two screens. And there is a distance between the two screens of 6 inches according to what you're planning.

Why don't we pretend we're Einstein and perform a thought experiment. Let's imagine you have everything set up and you're watching a 3D movie with your setup on your curved screen... Anamorphic lenses in place, and your geo box 602 video processor.

Imagine we have no automation and we have to now change our system configuration to watch content on a flat 2D screen that is at a different distance than the curved screen. We'll do the steps manually. And then it's up to you to find automation to do it for you.

A. Either remove the Geo box 602 from the video path or configure it to not process the video image in any way so that it does not introduce pin Cushing or barrel distortion.

B. Adjust the zoom, lens shift if needed, and focus of the projectors.

C. (Optional step) Slide the anamorphic lenses out of the way.

So how do you go about automating those three steps? Step b is easy. You have saved memory settings in your projector for the focus lens shift and zoom so it's as easy as calling up a memory setting.

Step A should be just as easy. There's got to be some configuration to turn processing on and off via some remote control code.

I presume you want the anamorphic lenses in place for your 2D screen. I'm not sure if it's scope but I recall your other threads where you want to use the anamorphic lens all the time.

-T
Re 1. My initial query was how do we measure a curved screen size. Someone responded he's not 100% sure but it's probably a very small difference either way so my query doesn't really matter. So I responded explaining why even a small difference matters for my situation.

In other words, my query is the "what." My response to the other poster is the "why." \

Re 2. I agree that if the geobox can correct the pincushion distortion from anamorphic lenses, then getting a curved screen because of anamorphic lenses is not necessary. However the curved screen is the 3D one that needs to be high gain, so the other reason curved might be beneficial is to reduce hotspotting on a 2 to 3 gain screen.

T-Bone, man, what do you want me to say? That you're not the only one annoyed by my posts sometimes? That's true, you aren't. Although I don't think saying anyone "admonished" me recently is accurate, and definitely not for changing the query. You accused me of doing that here, and I definitely did not. My query from the start of the topic was, and still is, how do I measure the width, by the curve or straight? Someone responded "probably straight" but he wasn't sure and said it would be close anyway either way so basically, it doesn't matter.

I posted my query. Someone explained a logical reason why it didn't matter, except that logic was based on not fully understanding why it's important in my situation. So I explained the why. That's clearly not changing the query here, which you accused me of, and I don't know which post you are referring to where you claim I did it in another topic. But yes, you are not the only person who has disliked a post of mine before. Really the main person who seemed annoyed with my questions a day ago ended up posting that I misunderstood and thought I was questioning him when I wasn't. So it was just a misunderstanding.

Really, some people take issue with posts if I don't even enough details. Some people take issue if I explain too many. The way you always describe my posts is to interpret them in a bad light and put me in a bad light. If you had a technical question and someone responded "it should be pretty close either way so it doesn't matter," do you think it would be fair to criticize you, or them? Of course Im not doing either. This poster was just trying to help. I'm just saying, you have a way of interpreting things where I'm always at fault, even when I'm not.

Sometimes I do change my query. A legitimate complaint about my posting would be like two weeks ago where I made a post asking for help with picking banana plugs, then halfway through I learned about right angle banana plugs fitting into much tighter spaces, so I changed to wanting that. Sometimes it happens when you learn new things in the middle of your thread. And I apologized for that, what more can I do?

Another time, I went back and forth like 40 posts with people trying to pin down the effect of brightness on anamorphic lenses, because I got bad info about that causing me to essentially buy projectors that were not bright enough, and that cost me almost \$1,000 to fix with new LEDs. And even though I knew nothing about it going in, it was me going back over and over, "I see what you're saying but I think it actually means this," that finally helped us figure out that actually what I was being told was incorrect, and what I had begun to suspect was the actual correct way.

So yeah, sometimes I ask a question, learn new things, and add new wrinkles to the question. Not in this thread, though. And other times, I ask a question, get a wrong, or incomplete, answer, that even though I don't know what the true answer is, I have enough eye for details and potential missing or incorrect variables to suspect the answers I got so far are either not true or not 100% of the story, so I keep trying to investigate.

I am new to HT, so some of my questions are very newb level, and this can annoy some people. On the other hand, sometimes I see or learn about details that much more knowledgable people don't, and I want to learn the full story and get really deep into it, and this can annoy some people. It's hard to please everyone on a forum. And maybe the fact that most people only care about 4K and 2D, and Im building a 1080p and 3D setup, means that most people are just basically bored by my setup questions. It's not something that has any overlap with their own interests or theaters, so it's understandable they'd be bored.

That's normal. It's not their fault, and it's not my fault. Why does there always have to be a villain? We're all here to discuss A/V gear and home theater, to learn, and to try to make our setups how we want them. What's your projector, JVC RS420 I think or something? If you were trying to learn 50 technical things about the JVC RS420, and were asking in all the appropriate threads, and those posts came up on my feed, would I enjoy getting 50 notifications of long technical posts about a projector I don't own, that has nothing to do with my setup? Maybe not, but I would understand, that's what the forum is for. No one has to read posts that don't interest them. And as for situations where you are tagging someone to ask them questions, again you can make me the bad guy and just act like I have a negative fifty IQ, and every answer I get makes complete sense and isnt missing anything important, but I'm just too stupid to understand it, but is that actually true?

You always criticize let's say my follow up questions, but have you once criticized an answer? Have you ever said, "tech asked a good question, and I see that you tried to answer, but honestly, this answer is wrong here, and it's missing this key information here"? I don't think you ever have. Just saying. And I'm not saying you should, because people are just trying their best to help and I appreciate that. But you don't always need to criticize my questions either. There doesn't have to always be a villain. We're all just posting the best we can, and it's never going to please everyone on the forum. Maybe there are people on the forum who don't consider your posts their favorites either, the way you don't seem to like mine? But they probably don't remind you of it nearly as often.

#### Technology3456

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Side thought:. Remember when me and other people told you you were making this way more complicated than it needed to be? You do know there are a bunch of people in AVS forum that have curved screens. And a bunch use anamorphic lenses. And they do it with a single screen and a single projector. What do they know that you don't know? That's what you ought to be asking yourself.

You should be asking yourself why there are so many people on AVS forum that decided to build their homes theaters with one projector and one screen. Imagine how Much they are missing out on with their simple configurations. Because they did it wrong. You know that you need two different screens and double stack projectors. You need to start a separate thread admonishing all of the users out there, including me, that shortsighted enough to use one projector and one screen. . Of course I'm joking but you get the point.

It's like you didn't really leverage any of the information that other users have. You said that you want 3d come hell or high water, and you are definitely going to use two projectors stacked and all of the issues that come with it, because you say so and what you want outweighs the experience and knowledge other uses on the board have. You don't even understand the history of why people double stack projectors in the first place. The main reason was during an era of dim projectors. So the double stacking was a solution to a problem that no longer exists. Although it exists in your case today. Keep reading and I'll tell you all about it.

You ended up buying projectors that are way too dim. Because you didn't do the research and what you actually needed. Oh, I know you did some research because you have the posts to prove it. But you didn't get the information that you needed. You insisted on telling everyone here that you were building your system all pieces at the same time because the interrelated. But when you try to build the system your way, things get dropped.

You are going to have a system not designed very well. You're going to have all sorts of problems between two different screens. But that's the way you want to do it.

If you leveraged the knowledge and experience of the other members, you could have had
• 4K HDR DLP projector 3D flat screen doing everything that you wanted it to do
• projector bright enough where you wouldn't need an anamorphic lens (although there is still a benefit for constant image height setups).
• No need for a curved screen.
• No need for double stack projectors.
• No need a high gain screen to compensate for your dim projectors.
• No need for a geo box 602 video processor.
• No need to spend \$1,500 to \$2,000 on madvr so you can tone map 4K HDR to work on your old technology projectors.

Your system is poorly designed and you have a whole bunch of Band-Aids to correct deficiencies that you introduced.

I could have set up a system for you in your room if you gave me diagrams in about a week, and that would have been me spending about 15 minutes a night looking at your problem for 7 days.

I don't have the best system, but it's nice. And I spent several hours last night in my game room watching 4K HDR content.

-T
We've been over this territory before. I like DLP projectors and I want passive 3D not active 3D. The only DLP projectors with good contrast are 1080p DLP projectors except ones that cost maybe \$100,000. The brightest home theater 1080p projectors are like 1,600 lumens. The 3D filters I would prefer to use take like 75% of the light. So on a 1.0 screen that's 400 lumens from the projector, enough for less than half my screen size. So no matter what projector I bought, to do 3D, I would need a high gain screen.

I can still just buy one screen if I want, a high gain screen, but apparently they're not as good for 2D. So I am getting the best of both worlds.

But you didn't get the information that you needed.
And why is that? I've done the triple crown: I've spent tons of time on avsforum asking experts. I've done tons of research myself, and I've asked tons of people in the industry, professionals. No one knows the answers to some of my questions because what Im trying to do is not commonplace and they have no experience with it. The info is not available, and sometimes bad info is given too.

Remember when I asked about different linear polarization filter alignments, and you told me there was only one? Would you have criticized me for listening to your advice too? I took the time to make the post on avs forum. A long time HT user and expert, you, responded with an answer. Remember what you just said, that I failed to leverage the experience of users on this forum. Well had I leveraged your experience, I might have wasted hundreds of dollars on the wrong 3D filters, because even experts get things wrong sometimes. Which is exactly what happened with the "too dim" projectors situation, but you are blaming me anyway. You understand I did a ton of research about that, but was given the wrong information by some of the most knowledgeable people on the entire forum? No one knows everything.

You act like I am constantly getting nothing but clear, 100% correct, answers to about A/V gear, and then foolishly ignoring it, but be honest with yourself, is that really what happened? Not to mention I bought my projectors off of advice from people on avs forum. You act like avs forum is a monolith where everyone advises the same thing. Is that true either? Like come on, why can't you even be fair about that. It's like you zone in on a few things to construct a negative narrative about me, and ignore the actual full picture.

But I got lucky with my projectors that it was possible to upgrade the LEDs, so it should work great. It would have worked regardless, with a 1.3 gain screen, just now it will really work well. In fact they're the brightest of all the DLP - LED projectors, at least the top ones. And they have almost 90% bt2020 coverage which I think is close to double the projectors you recommend me. Of course, what you recommend can do 4K. I would love to have 4K! There is no perfect product! Everything is a tradeoff! I am extremely happy with the type of projector I bought, and I think it will work great for me once it is set up in a way where it's working properly.

- The poster I think you brought up as admonishing me and being right, he said many in the thread would kill to have one of the model projectors I bought, let alone two, including him. So do you value his opinion when it's something positive about my project, or do you only bring up his opinion when you think it's critical of me?

#### T-Bone

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1. How much curviture is good for 130 inch 2.35:1 screen at 14 feet viewing distance? For use primarily with:
• Double stacked projectors for passive 3D, using two Isco IIIL anamorphic lenses, projected onto a, approximately, 2.5 gain screen
• And sometimes for use with 2D from one projector and one Isco IIIL anamorphic lens.
In addition to the Isco IIIL lenses, the signal to the projectors will go through a geobox 602 which can curve or uncurve an image, as well as correct for pincushion and distortion and barrel distortion I believe, or leave it be if that's what you want for a curved screen. Whichever way it needs to go, I think it can go, if that informs what type of curve to use.

2. If I get a 130 inch diagonal 2.35:1 curved screen, is that now less than 130 inches because of the curve? Like if I set up the geobox to make a 130 inch diagonal curved image, will it be calculating 130 inches length along the curve of the screen, or calculating it horizontally in a straight line (which would then require less length than the curved image, if you see what I mean. You get somewhere faster in a straight line than a curved line because it's a shorter distance. Depending on the curvature, either it would make an image 130 inches measuring horizontally, and maybe 135 inches measuring along the curve, or it would make an image 130 inches measuring along the curve, and maybe 125 inches horizontally, and when I plan my setup, I do not know which way it will measure.
Your original quote makes no mention of a second screen. You only mentioned one screen and that's curved screen for 3d. Your other use case is occasional 2D viewing with one projector. He probably assumed you meant 2D viewing on your curved screen. That post taken in his totality, I assumed you meant 2D viewing on your curved screen when projector.

As far as I know, most manufacturers only offer screens with one curve radius, and the amount of curve is calibrated to compensate as best as possible for the anaglyph lens. The radius is also usually large enough that the difference in the screen size and the distance between the edges is pretty small. Anyway, they generally seem to be measured by the width of the screen itself, not the distance between the left and right edges.
His response. The screen would be measured along the surface of the screen. Not the straight line distance between the left and right edge.

It would be a small difference but Im going to have a pulldown 2D screen like 6 inches behind a flip down curved screen if I go with a curved screen. I have no wall to use and no one manufacturers pulldown curved screens that I know of, so this would be the only way.

Meaning, I dont just have to align two projectors to the curved screen, I have to have the exact calculation on the projector throw distance, curved screen size, and distance between the curved screen and the pulldown screen behind it, that my projectors are aligned to both screens perfectly at different distances. Otherwise I need to realign my projectors every time I watch on one screen or the other, or I need different projectors for each screen. So basically the curved screen 6 inches closer will have to be slightly smaller than the pulldown screen, but it has to be very exact.

As for the amount of curve, apparently different throw distances with different anamorphic lenses, create different amount of curvature. So the correct curve for my lenses and throw distance might be different than someone else's. That's why I was asking how to determine that. If manufacturers only making one type of curve, then I guess these things arent as important as I thought? Because what if their own curve doesnt fit your throw distance and anamorphic lens(es)?
And your reply to him where you threw a monkey in the wrench by telling him that you do have a separate 2D screen that is 6 in behind the curved screen.

Throwing in that piece of information was definitely not related to your original query. And even if you were going to have two screens, which you told him later on about and not in the initial post, then it has absolutely positively nothing to do with a curved screen whatsoever in the original question. Why? Because when you have a curved screen your primarily concentrating on a perfect image without distortion. When you throw a second screen into the mix, that is at a different distance compared to the curved screen, you're solving a different problem unrelated to curvature. But rest easy, I solved that for you with my other post I made.

-T

#### Technology3456

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I could have set up a system for you in your room if you gave me diagrams in about a week, and that would have been me spending about 15 minutes a night looking at your problem for 7 days.
I don't want to put you on the spot or cause any embarrassment, but you keep saying things like this so maybe this is a good opportunity to get through to you that the reality is not as simple as the narrative you are constructing.

The DLP projectors I bought will calibrate 1,000 lumens each in overlap mode. On a 2 to 3 gain screen, so let's just say 2.5 for argument's sake, that is equivalent putting out 2,500 lumens per projector, calibrated. They are LED lumens so they will look even brighter, but I don't think we even need to factor that in to show that it's not easy like you thought. Just using the base number of 2,500 lumens equivalent when using 2.5 gain, after 3D filters take away 75% of the light, that leaves me with 625 lumen 3D My projectors calibrate to, minimum, with 2.5 gain.

The projectors does, minimum, 2,500:1 native contrast ratio.

So if it's so simple, then I'm all ears. What home theater DLP projector should I have bought instead, for use with a single 1.0 gain screen, that will put out 625 calibrated lumens after 3D filters take away 75% of its light, and that also has native contrast ratio even 2,000:1, let alone 2,500:1 or 3,000:1 like my projectors?

In other words, what DLP projector can you recommend that calibrates to 2,500 lumens, and that has over 2,000:1 native contrast ratio? Not 2,000:1 on the spec sheet, but real life measurements. My projector claims 100,000:1 contrast on the spec sheet, but obviously that's bs.

I'm not even sure a lot of the top 4K projectors can do bright 3D on a 1.0 screen my size (130 inches scope)! So again you've crafted an entire narrative where I'm an imbecile making the stupidest HT of all time, but in order to create that narrative you've had to ignore many facts and skew many things. And even if the projectors I bought dont end up providing 3D I like, I would most likely still keep 1 of the 2 because there is no other projector in my price range that can come close to the color gamut. The closest is the BenQ 9060, which has maybe 60% of the color coverage of my projector, but because it's like 80% brighter, the colors may look about even, let's say. And yet that projector has native contrast about 1/3 my projector, and outputs 24hz at 60hz not 24hz. Still I heard its fantastic but the black levels are probably five times worse than my projector, and the color coverage is 60%, although its brighter, 4K, and apparently the sharpest projector you can buy right now period.

There are always trade offs, but I made an informed well researched decision and bought absolutely fantastic projectors, by all accounts. Not just fantastic, but pretty unique under \$50,000 or whatever the cost is. If you don't believe me, believe the poster whose opinion you seem to value who said so. There is a love affair in the DLP community of avs forum with the 1080p DLP - LED projectors combined with madvr, because only with 4K UHD discs and madvr can their full potential finally be unleashed as far as the wide color gamut, and the ones I got might be both the brightest (of the 1080p ones with 2,000:1 or more contrast), and some of the best in other areas, of all of them. You act like I bought absolute crap. You should try reading the reviews for the projectors I bought, you might be surprised what you read. I read them all. Pick any one of them, they all say basically the same thing.

This is actually from the Nero 3d2 review, but it's a good representation.

In July of last year, I reviewed the M.150 SIM2 projector, which was a single-chip, LED-lit design. I came away from that encounter forever changed, for not only did the M.150 challenge the notion that one needed to have 4K for big screen viewing (you don’t), but it also redefined what it meant to be a benchmark product. The M.150, post calibration, measured better and performed higher than any projector I had seen to date, including the widely touted Sony VPL-VW1000ES, a native 4K projector, whereas the M.150 was merely HD. The M.150 was, and still is, prohibitively expensive for all but the top echelon in this hobby. I would argue that such performance often comes at a price. The buck stops with the M.150. I was so enamored with the M.150 that I tried to acquire it, but even I, what with my industry connections and accommodation pricing, could not make it happen. Rest assured if I could, I would. The M.150 did more than just upset my high-end apple cart – it ignited my newfound affinity for DLP.

• Read more video projector reviews from Home Theater Review’s writers.
• Find a screen in our Projector Screen Review section.
• Explore sources in our Blu-ray Player and Media Server review sections.

For years, I had been an LCD man, more specifically an SXRD and then later a D-ILA front-projection enthusiast. Despite reviewing a DLP projector here and there, none of them made me want to ditch my “chips” in favor of “mirrors” (remember that ad campaign). Then the M.150 came about and everything changed. In my quest to acquire the M.150 for both personal and professional reasons, I began to look at the concept of DLP on a whole and, in talking with SIM2 representatives, it became apparent that one of the traits that I found most attractive was the M.150’s single-chip fidelity. While I am aware that there are three-chip DLP projectors, the single-chip design and its inherent sharpness is something no multi-chip anything can match.
And yes madvr will cost me \$2,000 because of the computer. Apparently madvr's dynamic tonemapping is better than HDR 10 or Dolby Vision though too. So that will match possibly the best dtm available with a projector with some of the widest color gamut available, that is single chip and sharp like 4K...

#### Technology3456

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Your original quote makes no mention of a second screen. You only mentioned one screen and that's curved screen for 3d.
My original post didn't mention that I use Infinity speakers either. Why would I overcomplicate and make the post longer for no reason? I needed to know how curved screens are measured and spec'd, straight across, or along the curve. I know why I need to know, that's all that matters. Anyone who knows the answer to the question would not need to know further details in order to give the answer. Because he wasn't sure of the answer, and he said maybe it won't matter anyway, that is the only reason it became relevant to tell him, in order to explain why it matters for my setup specifically.

Your other use case is occasional 2D viewing with one projector. He probably assumed you meant 2D viewing on your curved screen. That post taken in his totality, I assumed you meant 2D viewing on your curved screen when projector.
It's totally irrelevant. Whichever way a curved screen is measured, that does not change if you project 3D or 2D onto it.

And your reply to him where you threw a monkey in the wrench by telling him that you do have a separate 2D screen that is 6 in behind the curved screen.
It's not a monkey wrench. No offense, you have misunderstood my meaning since the original post and continue to. Wasn't your first response to tell me that the curve is the same distance as the straight line because of the coke can and the bandaid? I'm not saying your coke can example was incorrect, but you definitely misunderstood what I was asking, and now you misunderstood this exchange with another poster.

To reiterate, all I asked for help with in this thread was how to measure a curved screen size, along the curve, or straight across. So far, no one knows the answer. One poster said it might not matter. Only in order to explain to him why it matters for my setup, even if it doesn't matter for ,ost, I told him about the other screen behind it. Now he understands why the original question matters for my setup, but the original question did not change.

Do you see what I'm saying?

Throwing in that piece of information was definitely not related to your original query.
That additional information was not a query at all, it was explaining why the query matters to my setup, which by definition makes it related. T-Bone...

And even if you were going to have two screens, which you told him later on about and not in the initial post, then it has absolutely positively nothing to do with a curved screen whatsoever in the original question. Why? Because when you have a curved screen your primarily concentrating on a perfect image without distortion. When you throw a second screen into the mix, that is at a different distance compared to the curved screen, you're solving a different problem unrelated to curvature.
You are confusing two things. Of course curvature only applies to the curved screen, but there is something that applies to both, right? Which is, the projected image needs to fit within the borders of both screen, and not be too small for one screen, or overlap over the border on one screen. So the projectors need to be aligned for say a 128 inch curved screen, and then have that same projected image, with no need to change the alignment, also fit into a 130 inch flat screen 6 inches back. It's about the size of the image, not the curvature. When I put one screen up and put the other down, one click ont he geobox can turn on or off the pincushion correction, or anything else curvature related. What cannot be solved with one button, what needs to be planned correctly from the start, is the size of both screens, their placement, and the projector placement and throw distance.

But rest easy, I solved that for you with my other post I made.
Not sure what you're referring to here.

#### Technology3456

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B. Adjust the zoom, lens shift if needed, and focus of the projectors.
Your advice is to adjust zoom, lens shift, and focus of two projectors every time I want to go from watching 2D on one screen to 3D on another screen? By all accounts that would be a terrible idea, and I listened to people's advice on the forum about that which is exactly why I posted this topic, to make sure I know how curved screens are measured so that I can calculate the correct size of each screen to make both screens aligned to the same projector placement, instead of having to re-align the projector each time for each screen.

You said that you want 3d come hell or high water, and you are definitely going to use two projectors stacked and all of the issues that come with it, because you say so and what you want outweighs the experience and knowledge other uses on the board have.
Plenty on the forum recommend double stacking for 3D over single projector 3D. You're doing that thing again where you equate your advice with the advice of every single other person on the forum.

The main reason was during an era of dim projectors. So the double stacking was a solution to a problem that no longer exists.
Others on avs have said that double stack 3D delivers the image to both eyes simultaneously, which provides 3D with less artifacts, motion blur, ghosting, etc. Single projector 3D still alternates images to each eye, so that problem still exists.

Is this really a good use of either of our time? The best way for you to help, and save both of our time rehashing this stuff, is to just tell me which home theater DLP projector that calibrates to 2,500 lumens and >2,000:1 native contrast (better yet, 2,500:1 - 3,000:1) that I should have bought. That would actually help me because I can still sell what I bought if I need to, and get something better for the same price if it's true I got the wrong ones, like you said.

#### T-Bone

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As for the filter thread, you mean this one here:. What's the difference between 135/45 linear...

You're a person who hardly ever watched any 3d according to your own posts. Yet when it comes to 3D it must be passive and not active. Why passive? I don't know, I think you said it's better than active? Maybe something about the refresh rate per eye. There are plenty of people here with very good active 3D systems. So this is the example. You have to have something regardless of what's available.... And regardless what other people have said about their active 3D systems.

And because of that constraint, well, everything I said in my post is still accurate. You've got this ripple effect because you're embracing antiquated technology of passive 3D.

So, could I design you a system? Sure I could. But remember when you throw in the initial constraint of filters that are going to reduce the lumen output by 75%, then that is a huge constraint. And that will limit choices.

I also had to check your post history to look for the post regarding the admonishment. Turns out you're having some problems with your projector and it's got smeared motion. Well enjoy your top of the line projector that cannot even reproduce motion. You probably bought d deffective unit. That's always the risk of buying used. There is no warranty. But that's a trade-off you made and there's nothing wrong with that. It just did not work out for you this time around.

-T

fatherom

#### T-Bone

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I'm dropping out. But remember, I did help you. Go back to my post where I told you how to solve all of your problems with a two screen solution, one being curved and the other one being further back and flat.

I'd appreciate you giving that post a like.

-T

fatherom

#### Technology3456

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As for the filter thread, you mean this one here:. What's the difference between 135/45 linear...
Yes that one. The question was what's the difference between the 135/45 linear polarization alignment, and the other one (which I did not know the exact angles at the time, just that it existed)? You responded "what exactly is your question?" even though it was clearly stated, and you also responded with:

I have no idea what you're asking. Therrr were more than 60 views and I guess your question was not interesting enough or detailed enough for anyone to reply. I only replying because I don't understand. And I think maybe you do not either?
You told me my question was not interesting or detailed enough for anyone to reply, which comes off like you know what, and which since you said you had no idea what I was asking, you shouldn't have thought yourself qualified to know in the first place. Then you suggested maybe I didn't know what I was asking, because since you didn't know I guess you assumed I must not? I knew exactly what I was asking, and it was clearly asked. "What is the difference between linear 135/45 linear polarization 3D, and 90/0 linear polarization 3D?" The only thing I didn't know at the time was that the angle of the latter option was 90/0, which I also stated in the post and was part of my clearly explained question.

You've already said you are not a 3D guy. And you like lcos projectors, not DLP. And you use 4K, not 1080p. And you use one screen. And have never used a curved screen. So basically everything I've been asking about, it's stuff you don't use, and probably have no experience with. Maybe you are just frustrated that you don't understand my posts? You have little familiarity or experience with any project similar to mine, and you don't understand the nuances of the questions, so it's frustrating and you feel the need to criticize me or something? I don't know but you should actually go back and look at your post history to have a wake up call just how many times you have done this exact same routine.

Why passive? I don't know
I don't think you do either so why do you have such a strong opinion about it? We have different preferences, it's not your home theater, and it's not your money, so why does it irk you so badly?

There are plenty of people here with very good active 3D systems.
I agree with you! They do. And the JVC NX7 is a great projector, but some people still buy the RS4500 I think it's called that costs three times as much because it's even better. I set out to build the absolute best 3D and 2D setup I could budget, according to what I value in a home theater, not what you value.

So this is the example. You have to have something regardless of what's available....
I don't even know what you're talking about. What I bought is also available, otherwise I wouldn't have been able to buy it. I don't know where you're going with this. Are you trying to say it cost more despite beign available? I don't know why you would say I wanted to have something "regardless" of what's available if that's what you meant. There is no "regardless," what I bought was available.

So, could I design you a system? Sure I could. But remember when you throw in the initial constraint of filters that are going to reduce the lumen output by 75%, then that is a huge constraint. And that will limit choices.
That's the same amount that active 3D glasses cut the lumen output, so I didn't throw in any initial constraint, this constraint has been there since I started my project along with many others you may or may not be aware of, which is why I said it's not as simple as the narrative you constructed. I thought you understood this aspect at least because you made the comment that double stack passive 3D was used in the past because projectors were too dim for active 3D. I thought that demonstrated that you understood active glasses on average actually take away even more light than a lot of passive 3D filters. Now I see what you actually meant is that you think when you double stack projectors for passive 3D, you get the light output from both projectors, but that is also incorrect. Well, one 3D company told me it's incorrect, the other told me it's incorrect, but since I've done so much research, I can give a 95% accurate judgment or so that it is incorrect.

In active 3D, each eye is seeing alternating frames, so each eye is getting the full brightness of each individual frame from the projector, just with the active glasses taking away like 80% of it. In passive 3D, each eye is seeing each frame from only one of the two projectors. One projector for one eye, one for the other. So it's still just one projector per eye, same as active. There is no brightness increase going from active 3D to passive double stack 3D, except for passive 3D filters generally being brighter than active. That is the only brightness advantage.

Could be wrong, hope Im wrong because then a 1.0 or 1.3 gain screen suddenly might work for 3D as well as 2D, but this is what I found in most of my research, with only one professional telling me otherwise, but I think he was wrong.

[QUOTE[I also had to check your post history to look for the post regarding the admonishment. Turns out you're having some problems with your projector and it's got smeared motion. Well enjoy your top of the line projector that cannot even reproduce motion. You probably bought d deffective unit. That's always the risk of buying used. There is no warranty. But that's a trade-off you made and there's nothing wrong with that. It just did not work out for you this time around.[/QUOTE]

I'm getting two of the same model so it's unlikely both will be defective. The one I have right now has under 200 hours on it total and everything is functioning well besides motion smear, so it's unlikely it is defective. I had the same problem on OLED and LCD TVs, but yes, a DLP projector is different so this would not be normal for it. If you read my posts you know I've only been able to test it for a few hours so far, with only one source, but you end your post "it just did not work out for you this time around" as if the issue is settled. Comes off pretty insincere. Other users on avs have compared LCD and OLED motion to lcos, because they all use liquid crystal, and I saw even worse motion smear on those technologies than I experienced so far with the M-150 I have. So if the M-150 is defective, that would just mean that even a defective DLP projector still has less motion smear than some 100% functional liquid crystal displays. So if you're telling me I should have gotten a new liquid crystal projector, you could be right but how confident are you that its motion would perform any better than my "probably defective" M-150?

#### fatherom

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1. You spelled "curvature" wrong.

2. T-Bone said "If you take a Band-Aid that's 4 in Long and wrap it around the sides of a Coke can... Is the Band-Aid still 4 in long? It is. The linear length of your curved screen does not change." to which you said "Wasn't your first response to tell me that the curve is the same distance as the straight line because of the coke can and the bandaid?" - are you even reading people's responses? T-Bone's response was completely correct, your response was a complete misinterpretation of what he said.

3. T-Bone said "Adjust the zoom, lens shift if needed, and focus of the projectors." to which you replied "Your advice is to adjust zoom, lens shift, and focus of two projectors every time" - LOL, another complete misinterpretation; he wasn't giving you advice...he was saying this is what you'll HAVE to do when switching between the screens, and I agree. If you think you'll be able to align projectors perfectly between two screens that sit at different distances from the projector, you're completely deluding yourself.

You seem to come on here to be affirmed, not to be informed.

You have a massive arrogance about the way you post. Yeah, I said "arrogance". I'm sure it's unintentional. But you seem to think other people's time is less valuable than yours, so you saddle the forum with doing a bunch of the work for you, taking time of their days to read and answer these massive tomes you write. Do some of the work for yourself. You come across as massively entitled.

I wish you would spend a lot less time writing novels to people who disagree with you, and work on your home theater instead of spending so much time typing.

T-Bone

#### Technology3456

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1. You spelled "curvature" wrong.
That's true.

2. T-Bone said "If you take a Band-Aid that's 4 in Long and wrap it around the sides of a Coke can... Is the Band-Aid still 4 in long? It is. The linear length of your curved screen does not change." to which you said "Wasn't your first response to tell me that the curve is the same distance as the straight line because of the coke can and the bandaid?" - are you even reading people's responses? T-Bone's response was completely correct, your response was a complete misinterpretation of what he said.
Just because you misunderstand the same thing he does does not change the fact you both misunderstand it just because there's two of you now. | is longer than ( if they both start and finish at the same points. I even made a drawing but... it's fine, it's fine. This is a waste of time so let me get to the next one quickly.

3. T-Bone said "Adjust the zoom, lens shift if needed, and focus of the projectors." to which you replied "Your advice is to adjust zoom, lens shift, and focus of two projectors every time" - LOL, another complete misinterpretation; he wasn't giving you advice...he was saying this is what you'll HAVE to do when switching between the screens, and I agree. If you think you'll be able to align projectors perfectly between two screens that sit at different distances from the projector, you're completely deluding yourself.
People do it all the time. Fixed screen on the wall for 2.35:1, and pulldown 16:9 screen a few inches in front, or vice versa.

You seem to come on her to be affirmed, not to be informed.
I think that's you guys. One of T-Bone's earlier similar arguments involved telling me I should have just bought the projector he has. It's like he takes offense that I could think there is a better projector for my preferences than the projector he owns.

You have a massive arrogance about the way you post. Yeah, I said "arrogance". I'm sure it's unintentional. But you seem to think other people's time is less valuable than yours, so you saddle the forum with doing a bunch of the work for you, taking time of their days to read and answer these massive tomes your right. Do some of the work for yourself. You come across as massively entitled.
I spend more time both on the forum, and researching, than either of you since I started my project, I 100% guarantee it, but that's normal for anyone who is doing a complicated project compared to people who already have theirs finished. Even with you guys derailing my thread about important info for my project, I've still spent more time posting in it trying to reason with two people who clearly like to post together, in a tag team, and clearly dislike me and for some reason resent my project, than either of you have.

Just look at the way you guys post. It's like my home theater is a personal offense and affront to you guys. Why? It seems to be because I am doing things differently than you guys, that I have different preferences, and you guys hate this because it does the opposite of affirm your preferences. That's why I said it's you guys who want to be affirmed. You want me to buy the same projector and screen as you guys have, and then say it's the best thing ever so you can feel like you have the best theater or something, instead of just accepting that different people have different preferences and it's not a reflection on your theaters.

And no, I don't think my time is more valuable than either yours or T-Bone's. Do I think your time is valuable? Of course not because if it was, you guys wouldn't spend hours messing with me on the forum every week or two, then wait for the heat to cool down, then start up again, together, a week or two later. But do I think my time is any more valuable? Clearly not otherwise I would have ignored you both the second or third time you did it, instead of falling for the bait and switch about fifty times now but still engage with you guys. This discussion proves that all three of our time is currently very low value, although since I've posted twice as long responses in this discussion, and had to reply to two people instead of just one like each of you has, that proves my time is currently the least valuable.

So you said I think my time is more valuable than you guys'. No, I admit it's less valuable at this point, but, we'd all be served well to find more productive things to do with our respective time in the future, which will then make each of our respective time more valuable in the future. But right now, yes I admit, my time is clearly the LEAST valuable. Otherwise I would sure be wasting a lot of value right now...

Lastly, I haven't seen anyone on the forum say "I don't know," or "I could be wrong," or "What am I missing?" as much as I have. Arrogant people are always pretending to know the answers to things they know nothing about. See any examples in this thread? If you're honest you will be able to find a handful of them from your friend, but you will point I misspelled "curvature," something completely irrelevant, before you will tell the truth about relevant aspects of your friend's post. Me, I'm usually asking questions, not pretending like I know answers I don't. I try to help relay info I read from other more knowledgeable sources sometimes, but I try not to claim to know things I don't.

#### fatherom

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Just because you misunderstand the same thing he does does not change the fact you both misunderstand it just because there's two of you now. | is longer than ( if they both start and finish at the same points.
If you truly think this, and you can't understand even a basic concept such as this, your project definitely will fail, because it's complicated, and because you can't understand basic concepts. You have TWO people telling you you're incorrect about this, and you still hold fast to your wrong conclusion. I'm done, too. I've subscribed to almost every one of your threads, because it's like watching a train wreck. I can't take my eyes off of it. This project will be a spectacular failure.

You COULD ask to be educated about why your '| is longer than (' conclusion is false, but I know you won't. Again, you don't come to this forum to learn.

T-Bone

#### T-Bone

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Just because you misunderstand the same thing he does does not change the fact you both misunderstand it just because there's two of you now. | is longer than ( if they both start and finish at the same points. I even made a drawing but... it's fine, it's fine. This is a waste of time so let me get to the next one quickly.
@fatherom was telling you the same thing I was telling you.

When I gave the Band-Aid example wrapped around a Coke can, the point I was trying to convey was that the linear length of the Band-Aid did not change. It was still 4 in. It doesn't matter that the distance from the left edge to the right edge, if using a straight line, is shorter than 4 in.

And the same holds true for your screen.

The linear length of your screen does not change. And I realize you even provided a diagram. But the diagram was meaningless to me and I'll tell you why:. I am a human being and I am not a geobox 602

Your initial post stated you were using a geobox model 602 and that model can process the image so that it looks appropriate on a curved screen. In other words no pin cushion and no barrel distortion.

That's the constraint of your question.

The issue you should have researched before you posted was to look at the geobox 602 manual. Maybe there is information in the manual that tells you what parameter to pass it? I've got the manual page open right now on my phone. Does it want you to put in the 130" in that's the linear length of your curved screen? Does it want you to put in the straight line value measure from the left edge to the right edge which is going to be less than 130 in? Does it want some other value that's not one of the two I've already listed?