Things seem to be on the slow side here for the past while, so I thought I’d share my weekend experiment with you.

I own an RS1 and have been trying to decide on a screen type & size for the past few weeks. My current screen is a 96” ST130 but it’s 1.85:1AR instead of 1.78:1 and as good as a Stewart screen is, the bright image of the RS1 reveals its screen structure and I find it distracting. Plus, I’ve been thinking about going slightly larger.

I recently saw a CIH setup with a HP screen (thanks to another forum member) and was very impressed. I originally dismissed this thinking that if I accommodated a 2.35:1 width my 14’ wide room, the 16x9 image would be smaller than what I’m used to. I started thinking about a 133” diagonal (16x9) screen, which worked out perfectly for many reasons – everything would be larger than I was used to and max throw distance put the projector at the very rear of the 26’ long room (on top of current equipment rack). However, I couldn’t get the memory of the CIH setup I saw out of my mind, so recently I experimented with moving my L/R speakers a little more apart and decided I could fit the width. I was ecstatic until I realized that max throw would be about 20” or in front of my equipment rack. I’d have to live with the projector being on some form of platform behind my 2nd row of seating (but well enough in front of my equipment rack that I’d have room to maneuver) or figure out what size screen increase I’d need to push max throw to rear of the room. The projector currently is on a makeshift platform behind my 2nd row, but it does look a little weird and I prefer the back of the room (I don’t want to ceiling mount as I’m trying to keep it at about 5’ for HP reasons).

The math came out at a 100” wide 16x9 screen – which is a 11’ wide 2.35:1. I had to further tweak L/R speakers to squeeze this in, but I was concerned about the image being too large for my seating distance (of 12.5’) so as an experiment I went out and purchased a bunch of ¼” thick poster boards and built a makeshift screen. I put this together Saturday and tried it out using the zoom method… wow – I couldn’t believe the experience of watching it – talk about immersive. Even with 110 hours on my RS1 and with the projector at about 2.4 throw distance, the image was fairly bright and resembled film. Even with the seams of the poster board showing, it was a delight to watch. It’s perhaps too big at times (with busy camerawork) but overall it was one of the most impressive images I’ve seen. I spent all day Sunday playing clips of various movies. I was surprised at how detail held up at that size. I thought film grain was going to be over-pronounced at this size, but it was the opposite – probably because the image wasn’t as bright – most movies looked better overall – or more like projected film. I found myself noticing details in scenes that I was very familiar with – because the size permitted me to do so. The Empire State Building scene in King Kong was a revelation.

I feel like I went from having a ‘home theater’ to having a theater in my home. :-)

That’s exactly what I did when I went from a 1.78 screen to a 2.35 screen. My walls were already painted so I made a poster board screen also.

Blackout cloth from the big rolls at Jo-Ann's is 54" wide, so you can make a 2.40:1 screen up to near 130" pretty easily, in one piece, and if you like it, you can leave it up. Buy, cut, tack to the wall. You're done. :D

(But it's not as cheap as poster board.)

Of course you can just skip to the end and buy an HP screen sight-unseen*.

(*HP fanboi here. :))

[QUOTE=Ian_Currie]Things seem to be on the slow side here for the past while, so I thought I’d share my weekend experiment with you.

I own an RS1 and have been trying to decide on a screen type & size for the past few weeks. My current screen is a 96” ST130 but it’s 1.85:1AR instead of 1.78:1 and as good as a Stewart screen is, the bright image of the RS1 reveals its screen structure and I find it distracting. Plus, I’ve been thinking about going slightly larger.

IAN-

Hmmm, the Stewart Studiotek 130 at 96" is exactly what I was considering going with. You say that you can discern "structure" with it? Would this be the so-called "sparklies?" If this is so, then I would think that something with even less gain would be advisable ??? Comment?

Hmmm, the Stewart Studiotek 130 at 96" is exactly what I was considering going with. You say that you can discern "structure" with it? Would this be the so-called "sparklies?" If this is so, then I would think that something with even less gain would be advisable ??? Comment?

I don't know if I'd call them sparklies - they don't look like glitter. If you examine the surface of an ST130 it does have sparklies, but it's very textured - feels like sandpaper and with a bright light on it I can see the texture - especially during pans, etc. However, I should point out that:

1) Others have reported NOT seeing the structure with this screen. YMMV.

2) I have my projector positioned in the middle of the screen, just a foot or two above my head (as one would with an HP screen). While I haven't tried ceiling mounting it, I did try raising it up another foot and the screen texture was reduced. Perhaps on the ceiling the angle would change enought that it wouldn't be an issue - not sure.

All I know is that I hate it. It's like adding extra grain to the image.

I recently saw a HP screen and it showed no screen texture whatsoever.

Ian,

"I recently saw a HP screen and it showed no screen texture whatsoever."

HPs are very good about that.

They have one type of potential defect too. Sometimes you can get a tiny little dot of what is basically very very high gain from the screen. They are *extremely* angle dependent when you see them, move your head just a small amount and it disappears. It is likely due to an inconsitency in the screen itself and as such will vary between different screens. On mine I've seen this for a few different seats in my room. The HP we saw was very good about this, I saw only it from one place. It is a pretty minor thing (IMO) compared to seeing a surface 'grain' like you are talking about but worth mentioning.

Shawn

Which "zoom method" are we talking about here?

I've thought about buying some extra velvet to blackout the top & bottom of my 133" 16:9 HP. I figure that will give me 90% of the performance of a real CIH setup.

Zoom method for CIH is very simple. You use a 2.35 screen. For 1.78/1.33 material you zoom the projector such that the image fills the height of the screen. When you put on 2.35 material you rezoom the projector such that the active image again fills the height of the screen. This will also mean it fills the width of the screen.

You need to get the projector within the throw distance where it can be zoomed to both setups.

It is much cheaper then using a lens and scaler. With motorized zooms this can be done pretty easily by remote if the offset/focus doesn't change when zooming.

Shawn

Zoom method for CIH is very simple. You use a 2.35 screen. For 1.78/1.33 material you zoom the projector such that the image fills the height of the screen. When you put on 2.35 material you rezoom the projector such that the active image again fills the height of the screen. This will also mean it fills the width of the screen.

You need to get the projector within the throw distance where it can be zoomed to both setups.

It is much cheaper then using a lens and scaler. With motorized zooms this can be done pretty easily by remote if the offset/focus doesn't change when zooming.

Shawn

I've never understood why it is considering more desireable to have black bars on the sides of the screen rather than at the top and bottom.

"I've never understood why it is considering more desireable to have black bars on the sides of the screen rather than at the top and bottom."

Simple... because in a constant height setup the widest aspect ratio material is show in the widest format and takes up the entire screen. Just like in a theater. The widescreen material is shown in W-I-D-E-S-C-R-E-E-N. Not shown smaller then 1.78 material. It is far more theatrical feeling.

For those that are worried about black bars it is much easier to mask the sides of the screen then it is to do it for bars at the top and bottom of the screen. One could setup curtains to do this very cheaply and easily for example.

CIH is one of these things that it is much easier to get the point across simply by showing it to someone in action then trying to explain it on a forum.

Shawn

I don't know if I'd call them sparklies - they don't look like glitter. If you examine the surface of an ST130 it does have sparklies, but it's very textured - feels like sandpaper and with a bright light on it I can see the texture - especially during pans, etc

OK, now you have me worried. I just had a ST130 delivered today (recommended for the RS1 by a VERY knowledgeable sales person well known here) for an RS1 due in a few weeks. OTOH, it will be ceiling mounted and at about 17 feet throw on a 120 inch wide anamorphic ST130.

Thoughts? Or am I just worried for nothing?

"I've never understood why it is considering more desireable to have black bars on the sides of the screen rather than at the top and bottom."

Simple... because in a constant height setup the widest aspect ratio material is show in the widest format and takes up the entire screen. Just like in a theater. The widescreen material is shown in W-I-D-E-S-C-R-E-E-N. Not shown smaller then 1.78 material. It is far more theatrical feeling.

For those that are worried about black bars it is much easier to mask the sides of the screen then it is to do it for bars at the top and bottom of the screen. One could setup curtains to do this very cheaply and easily for example.

CIH is one of these things that it is much easier to get the point across simply by showing it to someone in action then trying to explain it on a forum.

Shawn

I understand what you describe. It seems to me, though, that for 1.78 material you are wasting a great deal of the screen surface. I suppose it's a matter of the relative proportion of 2.35 and 1.78 material that you watch.

In my relatively narrow room (~13 ft) I have about the widest screen that will fit (110" W), considering speakers, etc. If I went with a 2.35 screen, it would be only 47" H, compared to the 62" H that I have with a 1.78 ratio. And if I then masked it down for 1.78, it would be only 84" W, i.e. much smaller than what I have.

OK, now you have me worried. I just had a ST130 delivered today (recommended for the RS1 by a VERY knowledgeable sales person well known here) for an RS1 due in a few weeks. OTOH, it will be ceiling mounted and at about 17 feet throw on a 120 inch wide anamorphic ST130.

Thoughts? Or am I just worried for nothing?

Like I said, your mileage may vary. See this post for a positive report on the RS1/ST130 combo:

http://www.avsforum.com/avs-vb/showthread.php?t=834980&page=3

"It seems to me, though, that for 1.78 material you are wasting a great deal of the screen surface."

I am not wasting any screen for 1.78 material. My setup was height constrained. On the 2.35 screen my 1.78 material is the same size it would have been if I went with a 1.78 screen. The bonus is that the 2.35 material is shown larger, not smaller.

In my setup it was a no brainer.

Shawn

"It seems to me, though, that for 1.78 material you are wasting a great deal of the screen surface."

I am not wasting any screen for 1.78 material. My setup was height constrained. On the 2.35 screen my 1.78 material is the same size it would have been if I went with a 1.78 screen. The bonus is that the 2.35 material is shown larger, not smaller.

In my setup it was a no brainer.

Shawn

Very good point. So if one is 'height constrained', a 2.35 screen is good, because you get more width for the fixed ht; but if one is 'width constrained', then a 1.78 screen is better since you get more height for the fixed width.

Very good point. So if one is 'height constrained', a 2.35 screen is good, because you get more width for the fixed ht; but if one is 'width constrained', then a 1.78 screen is better since you get more height for the fixed width.

Well, that depends.

I've been fooling around with the CIH idea and find some things appeal to me that are not predicated solely on "how big an image can I get?"

For instance, I very much like the idea of being rid of the black bars, where a portion of the screen is not used. So much so that I have gone to lengths to mask even my plasma for wide scope films. The effect of having the image completely bordered by true black is significant and I'm addicted to it (and everyone who has seen the masked vs unmasked version of a scope film on the plasma agrees that it really is an agreeable improvement to the viewing experience). Some might assert the black levels of the latest projectors make the unused portions of the screen a non-issue - that they are black enough to ignore. My experience with these projectors disagrees, and I know they too would benefit by having only the active image area surrounded by real black. It's something you might not know you are missing, until you try it.

CIH removes the black bars on scope films, making the image fit the screen allowing for the image to float against black - no black bars. Further, it is generally much easier to mask from the sides than from top/bottom, so masking for 16:9/1:85:1 content, to maintain the no-black-bars scenario for all content, would be easier in the CIH set up.

Then there's the "scope movies should be wider than non-scope movies" factor. Which makes sense. It does seem a bit odd in a 16:9 set up that the movies shot for the greatest impact and immersion factor should be the ones that are most diminished, visually. Strange that The Last Samurai or 2001 Space Odyssey ends up with significantly less screen real estate than The Forty Year Old Virgin.

It seems virtually everyone who sees a CIH set up comes away impressed by the sense that widescreen films really do take on that special dimension that was intended for them, vs non-scope films.

Finally, something else I've found appealing: In my room I could fit a screen the width of about 107 to 110" or so. My seating distance being about 11 feet. Even taking the 107" width, that would be a 122" diagonal 16:9 screen. Frankly, from my seating distance, I don't think I'd care to watch everything I view at such a ginormous image.
Maybe some would, but not me. I think even many HD broadcasts can benefit from not being blown up so huge in front of me, and will actually look better at a smaller size (not to mention brighter and punchier).

I'm a film lover, not a TV watcher in general. I'm finally going the projector route because I find the new sources for film - the HD sources, HD-DVD/Blu Ray - finally provide the resolution to have nice big image sizes without the previous limitations of SD resolution being thrown in my face. So I'll be watching tons of HD movies.

I like the idea that with, say, a 106" CIH screen width, my 16:9/non-scope movies will not be blown up to overwhelming size, and will likely generally benefit from being shown somewhat smaller (about 92" diag) - all the better for clarity and punchiness of image, and viewing comfort. And then I like the idea that a widescreen movie will produce a "special" viewing experience, in terms of immersion. (And with increasing numbers of HD movie content to choose from, the clarity of the scope films at that size should be fine).

Then too, there's the fact scope screen just look friggin' cool. They give a different "tingle of anticipation" just looking at them, and it makes a 16:9 look stunted, square and run-of-the-mill in comparison. :-)

There are some compromises in the CIH idea that I'm not sure about, but the above describes what I find appealing about it, in my situation, and as I said it's not specifically centred on "how big an image can I fit on my wall?"

Cheers,

Good post, Rich.

Rich: Very well-stated, and I certainly appreciate the points you make. But with my 110" availability for screen width, I have a 126" diag 9x16 screen. If I had a 110" W 2.35 screen, when it was masked for 1.78 HDTV I would have a 96" diag 9x16 screen. Going from 126" diag to 96" diag makes an enormous difference IMHO (I played a lot with projecting different sizes on my wall before finally choosing a screen); and when my room is totally dark, as it is when we watch movies, I really never see, or at least notice the black bars at the top and bottom. But that's what's great about this hobby--there is enough flexibility now so that everybody can pretty much set things up to their own preference.

mililerwill, what is your seating distance? I would think that plays a role in the equation. Also, when people have home theaters with more than one seating row, I can see that affecting the decision as well. I'll only have one seating row.

mililerwill, what is your seating distance? I would think that plays a role in the equation. Also, when people have home theaters with more than one seating row, I can see that affecting the decision as well. I'll only have one seating row.

My wife and I sit with eyes ~ 13 ft from the screen, and there is only 1 'row' of seats, ie just our 2 recliners. (There is a couch on the side of the room, and the view from there is also amazingly good, in spite of all the discussion of the 'viewing cone' of the HP screen.) My room is not a true HT, but rather a former master BR, now an informal den, in an 80 yr old house, but it works surprisingly well for just a 'personal' HT. I should take some pics to show what can be done with such.

mililerwill, what is your seating distance? I would think that plays a role in the equation. Also, when people have home theaters with more than one seating row, I can see that affecting the decision as well. I'll only have one seating row.
Seating distance is a HUGE factor in this equation. From 1-1.2 SW the RS1 produces an amazing combination of PQ and immersion on HD scope movies. However, most 16:9 material is too overwhelming at this distance. If you only have one row, a 2.35:1 screen can be the best of both words. :) OTOH, from a seating distance of around 1.5 SW, CIH usually doesn't make as much sense because you just wind up with a smaller (likely too small) 16:9 image.

I obviously agree that seating distance is imp. If I went with a 2.35 110"W screen, the width would come down to ~84" when masked to view 9x16 material. And from my 13 ft viewing distance, this would be a distance to width ratio of ~ 1.9; i.e., the screen would be so small that 1080p isn't even worth it. While with my 110"W 9x16 screen the ratio is ~ 1.4, just about right (for me).

I am sitting 12.5' away from a 11' wide screen, which puts it at 1.1 SW. This is slighly overwhelming with busy camera work (but very immersive) and necessary if I wanted to retain the same SW for viewing 16x9 material that I had before going CIH (1.5 SW).

I am sitting 12.5' away from a 11' wide screen, which puts it at 1.1 SW. This is slighly overwhelming with busy camera work (but very immersive) and necessary if I wanted to retain the same SW for viewing 16x9 material that I had before going CIH (1.5 SW).

I agree with your finding re 9x16 screen size: though some people like it much closer than 1.5 SW, I can only go to ~ 1.4 before I find it overwhelming. (I had originally planned on a 133" diag HP 9x16 screen, which would have put me at 1.3 SW; but after projecting this size on my wall for a couple of weeks, I cut back to 126" diag. Doesn't seem like much difference, but I really noticed it!)

If I could have a 126 diag 9x16 screen, after a 2.35 screen were masked, then I would certainly be happy to do this. But this would require my 2.35 screen to be ~146" W, and I just don't have room for this. As discussed above, my room is 'width limited', i.e., relatively narrow (but this does help with regard to the viewing angle for the HP screen).

Just a thought: since the limiting factor - at least biologically - is the ability for humans to take in wide images, why aren't we talking about constant image width? Wasn't Cinemascope and the like simply a marketing device designed to bring people back into the cinemas at one point? (At least I think that is what Scorcese said in his History of Cinema DVD.) What is so sacrosanct about height? Based on the biological constraints at the sizes we are talking about, wouldn't it make more sense to have constant width images?

(this ought to get some discussion going :) )

Personally speaking, I am going to paint my entire wall in order making one giant screen. Then I can experiment to my heart's content. Once decided then I only need to deal with screen masking, if I feel the need.

Just to demonstrate how bored I am, here's a comparison of display styles (don't kill my temp site):

http://personal.linkline.com/shadow/theater/screensizes/index.html

Note that constant width places what is likely the least high-quality signal as the largest, while the most detailed and engaging is smallest. Constant Area I think still rules the roost for most applications, but is just not worth the effort for anyone without an engineering degree.

The one thing that does stink about constant height is the small 4:3 image.

Just to demonstrate how bored I am, here's a comparison of display styles (don't kill my temp site):

http://personal.linkline.com/shadow/theater/screensizes/index.html

Note that constant width places what is likely the least high-quality signal as the largest, while the most detailed and engaging is smallest. Constant Area I think still rules the roost for most applications, but is just not worth the effort for anyone without an engineering degree.

The one thing that does stink about constant height is the small 4:3 image.
Very interesting. Thanks for doing this.

For me, I mostly watch movies or HD broadcasts so i think 4x3 will in the long run be less of a concern. That just leaves 16x9 and 2.35. Since most of the material I watch now seems to be 16x9 I would make/get the widest 16x9 (1.78) screen possible so as to not "artificially" diminish the size of this ratio. This way both 2.35 and 16x9 would both be very immersive.

As for how wide, to me there are 2 factors both of which of course depend on the seating distance:

Speaker placement - what is generally recommended is a equilateral triangle between the fronts and the "sweet spot" - at least for stereo listening.
Viewing angle - SMPTE recommends 30 degrees maximum

Note there is an interesting site with a seating distance caculator that lists various standards: http://www.myhometheater.homestead.com/viewingdistancecalculator.html
Unfortunately it only covers 16x9 and 4x3

Martin

I upgraded my screen from a 92" wide HP (1.85:1) to a 120" wide(2.40:1) HP. My room is 15' wide by 28' long with 10' ceilings. It is not a dedicated theater and I do not have theater seating. I had my doubts before, but after using this setup for a couple of weeks I can see why people like the CIH. I haven't installed side curtains yet, but plan to do so. I have masking above and below the screen. For some reason the black bars on the side are not near as distracting as they were when on top and bottom.

I sit further back than most, about 1.6 to 1.8 screen widths. The 1.85 piture is almost the same size as before, but the scope movies take it to another level. It really gives you the theater feeling. Also I am glad I got the HP as I wouldn't want a dimmer picture. For movies where I fill the screen I am already down to 14.84 ftL with the RS1. I'm sure I will be under 10ftL toward the end of lamp life and I sit toward the side of the screen so I'm seeing even less.

I upgraded my screen from a 92" wide HP (1.85:1) to a 120" wide(2.40:1) HP.

Why did you go with 2.40:1 over 2.35:1?

If I had it to do over again I would probably go 2.37 or 2.38. As I said and others have noted, the bars on top and bottom are more bothersome than the ones on the side. Even without side curtains I hardly notice the small sidebars on a 2.35 movie. I could enlarge a 2.35 AR movie and have a bit of spillover on top and/or bottom and no bars. You could also enlarge a 2.40 movie to fill a 2.35 screen with no bars also. Pick your poison. :)

I wouldn't have had much of an opinion on the subject until last year when I saw either Vidikron or Runco's display at CES. They had a really expensive curved screen with motorized masking. They also uses a motorized anamorphic lens on the projector.

Seeing the image get wider rather than getting smaller was VERY impressive. A widescreen movie is supposed to be wider, not shorter. I understand that it is all relative. But it was very impressive, and after only a few minutes made a believer out of me.

It's also worth noting that if a director shoots in 2.35:1 he is shooting with the idea that image will be wider than normal, not shorter.

I guess you should calculate seating distance based on screen height when you are going for constant heigh.

Martin brought up a very important point- Speaker placement. I would venture to guess that it would be best if not critical to use an acoustically transparent screen. That little detail really makes a home theater feel like a real theater. My Dad's theater has a perforated screen with some amazing sounding Genelec speakers. Having the center channel behind the screen really makes a difference, especially on a big screen.

Unfortunately for me CIH isn't practical or affordable.

~Jay

Very good point. So if one is 'height constrained', a 2.35 screen is good, because you get more width for the fixed ht; but if one is 'width constrained', then a 1.78 screen is better since you get more height for the fixed width.


I think that's probably the way most people feel - all other things being equal, just make each image as large as they can. For most rooms, this means constant width.


That just leaves 16x9 and 2.35. Since most of the material I watch now seems to be 16x9 I would make/get the widest 16x9 (1.78) screen possible so as to not "artificially" diminish the size of this ratio.


As a constant height proponent, I would say that even if you only watch a small amount of 2.35 material, if it's very important to you (LOTR trilogy? Matrix trilogy?), it's worth diminishing the size of 16x9. Constant height is all about maintaining the proper scale.

Here's a silly example: I give you 8 sheets of paper and tell you to draw Snow White and the seven dwarfs, one character per sheet. Based on the arguments above, you would draw all characters the same size: there's more smaller material (seven dwarfs vs one Snow White) and you utilized the maximum page space available. When you line them up side-by-side, will that look "right" to you?

I-Liang

I have had my CIH setup for a little over two years. Two rows of seating first row 13’ and second row 19’. I started out with a 92” X 52” 1.78 screen. When I switched to 2.35 I picked out a 118” X 50” screen. This gives me an 89” X 50” 1.78 image. Now for the strange thing. I prefer to sit in the first row for 2.35 movies and the second row for 1.78 stuff. It must be in my head, but it seems that the height of the 1.78 image is too high for its width. It may be eye movement, left and right for 2.35 stuff and up and down for 1.78. Does this make any sense? Anyway, I do like the CIH setup.

Based on the arguments above, you would draw all characters the same size: there's more smaller material (seven dwarfs vs one Snow White) and you utilized the maximum page space available. When you line them up side-by-side, will that look "right" to you?
In the end it seems apparent to match your projection type to your viewing habits. If you're only watching 4:3 content, then constant width is your ticket. If you are watching mostly 16:9 content, then constant width with a 1.78 screen is your ticket (I added the 16x9 screen comparison).

However for most of us here, who probably watch mostly HD content at 2.35:1 or thereabouts, the constant height scheme provides the most screen size per watched minute.

If you can do adjustable masking, a modified constant area scheme is still the best overall presentation, to preserve the size of a 4:3 image (and 16x9 with a small bump in size).

I don't see the big deal... I use the ISCO III and you just rotate the lens until it fills the width of the screen... I mean this is the first time you set up the lens. I don;t mean you have to change it... Every single HD-DVD or Blu Ray HD movie 2.35/2.4 always fills the screen to the same degree that I have seen... I just don't see the problem. I do not see any variation between movies labeled 2.35 or 2.4 upscaled DVD or Blu Ray... The width and heigth seem constant to me... And I move the lens out when 2.35/2.4 material is not being played. I've had my setup for a year and honestly, I can;t imagine you'd see the difference between 2.35 and 2.37 and 2.4