Film-Tech Forum ARCHIVE: Curved Screens vs Flat Screens

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Posted by Joe Redifer (Member # 3) on 10-07-1999, 05:09 AM:

How does everybody feel about their screens? Personally, I like flat screens better due to less distortion. On the same subject, what about AMC's TORUS compound curve screens? I think that they REALLY SUCK! I have never seen such an awful image in my life. AMC was using a 7000 watt xenon on a 50 foot TORUS screen and it was still too dim! Plus the sound sucked, due to no speakers behind the screen.

Posted by Aaron Mehocic (Member # 15) on 10-07-1999, 02:04 PM:

Got to agree with flat screens being better. We have two out of nine curved screens and the distortion is really noticible. Plus, curved screens don't look good when your canging the masking from flat to scope because the masking doesn't bend exactly with the screen. In short, the two curved screens are just pains in our asses!
AMC screens? Don't know much about them. Don't want to either from the reputation they have on this forum!

Posted by Brad Miller (Member # 2) on 10-07-1999, 03:23 PM:

I cannot stand curved screens. Every theater I've ever been to with them has had focus problems (which is the main reason to supposedly put them in).

I also don't like the lack of width in the aspect. Take yourself a flat screen and curved screen in identical auditoriums and mask the image perfectly, the curved screen will not appear as wide to the audience...makes flat films look more like a big TV.

The biggest beef I have though is with the distortion associated with them. Anyone see the THX Broadway logo on a curved screen? Suddenly that nice rectangular box becomes a big blue smiley face! A wide shot of New York city looks like the skyscrapers are leaning inwards about to fall like dominos.

And what's up with the poor light dispersion? Some of the larger curved screens in town cannot prevent a horizontal hot spot, depending on where the viewer is seated depends on it's location on the screen. Also, I don't like the "washing out" effect curved screens have on contrast. The left side of the image DOES bounce into the right side and vice versa.

Joe put it nice and blunt: "curved screens suck".

If a new 20 plex was to open boasting "extra long narrow hallway auditoriums", people would flock to see movies there! It's amazing how powerful advertising can be on the general public as opposed to quality. Just look at "stadium seating"!

Posted by Ian Price (Member # 14) on 10-07-1999, 05:25 PM:

The funny thing is that all the lens companies grind their lenses for the flat screen. All modern lenses are specifically made for flat screens. You are supposed to get special lenses for a curved screen. D150 anyone?

Bobby Pinkston told me that one when Larry Jacobson changed all the flat screens at the UA Greenwood to curved screens. Larry Jacobson used to be head of engineering at AMC. Guess where they got all those "suck screens"?

Posted by Bruce McGee (Member # 131) on 10-07-1999, 07:12 PM:

In the 1980's Atlanta was fortunate to have the Columbia Theater on Peachtree St. It featured the (then) "largest screen in the south." It had a substantial curve to it also. The projector was a Cinemeccanica(?) with 35/70 capabilities. Dont know the model. The lenses were custom ground for the theater. I didn't work there, I just knew the projectionist.
The sound was fantastic, and the screen focus was razor sharp.
I saw Oklahoma! there in about 1983. It was run at 30 fps. The focus and the 70mm combined to look like you were looking in a mirror.

I wish we had some 70 theaters here in Asheville. All 35 here.

Posted by Rick Long (Member # 213) on 10-07-1999, 08:58 PM:

Curved screens may be O.K. for a near-zero projection angle, but in all to many cases they are used with relatively steep projection angles.

The result of this, when setting up the masking in preparation for aperture filing, is that while the .690 line (using RP-40 for Cinemascope) is at the bottom centre of the screen, the lower left and right edges of the screen (as viewed from the projection room) "dip" down into the next frame.

The only alternative to avoid negative "flashes" is to set the lower .690 line to
the lower left and right edges. The resultant bottom centre crop loses a lot of picture. The problem is even more pronounced when setting .446 for 1.85).

Posted by Christopher Seo (Member # 7) on 10-08-1999, 04:43 AM:

Wait, Brad... what's wrong with stadium seating? Besides the fact that audience members in the last row of our auditoriums occasionally play shadow puppets with the slides and end titles?

Posted by Erich Loepke (Member # 166) on 10-08-1999, 05:36 AM:

My most recent experience with a curved screen was when a friend and I went to see "The Phantom Menace" at the Regal 20-plex. In addition to the scratched and dirty film, I had to put up with very noticeable image distortion. It was like watching the film through a fish bowl. Gee, I don't have this problem at home with 16mm. Of course, I mentioned the scratches to my friend and he didn't notice them until I pointed them out. There seems to be more emphasis put on sound and sound systems these days than on good quality images. I don't go to the theater just to hear a set of speakers. I can do that at home. I'm sure a lot of moviegoers are taken in by buzzword advertising (Torus compound curve as mentioned above). It sounds good, so it must be!

Posted by Joe Redifer (Member # 3) on 10-08-1999, 03:52 PM:

Once AMC stops getting box office results from their Torus compound curve screens, perhaps they will try a reverse Torus "pertruding screen". Hey, every gimmick has gotta be tried!

Instead of having "The Screens That Suck" AMC will have "The Screens That Blow".

Posted by Gordon McLeod (Member # 33) on 10-08-1999, 07:32 PM:

I have always been a fan of curved screens but regretably very few are properly designed let alone installed
To prevent cross reflection the screen must be a high gain (silver)
The projection angle cannot exceed 3 degrees or you will get curved verticle lines(barrel distortion)
Most new lens work fine on a screen curved on the radius of the projection throw. A deeper arc requires deep focus lens and both ISCO and Schnieder offer them
Check out many of the big D150 theatres and notice that the curvalon lens had no distortion with screens arced on 150 degree field of view

Posted by George Roher (Member # 91) on 10-09-1999, 01:04 AM:

I love curved screens. You just need deep-curve corrected lenses. The curved screens I've seen in new multiplexes are pretty much garbage, but a giant curved screen set up properly is the ultimate film going experience. It just feels more three-dimensional.

Posted by George Roher (Member # 91) on 10-09-1999, 01:05 AM:

I love curved screens. You just need deep-curve corrected lenses. The curved screens I've seen in new multiplexes are pretty much garbage, but a giant curved screen set up properly is the ultimate film going experience. It just feels more three-dimensional.

Posted by Joe Redifer (Member # 3) on 10-09-1999, 03:00 AM:

I have found that the more curve is in the screen, the more cropped your picture is. Look at the aperature of any curved screen. The more severe the curve, the more the aperture is carved like a bow-tie.

I just don't like cropped pictures.

Posted by Stephen Jones 1 (Member # 114) on 10-10-1999, 04:47 AM:

Though I'm not speaking for Brad, one reason why he may not like stadium seating is for the following reason:

Pretty much all theatres want to get the maximum seating capacity in their auditoriums, which in turn means the slope of the stadium seating going almost to the top with the porthole about 5 to 10 feet above the last row. Problem is that the roof is not much higher than about 8-12 feet above the porthole if that much. Therefore, many stadium seating theatres have to angle their projectors downward so much that the keystoning can be almost in impossible to focus an anamorphic image. Most of the time with these theatres, the center is focused with the top and bottom very blurry. With flat seating, the projector can be set up to have almost no angle onto the screen; a perfectly straight image on the screen.

Posted by Scott Norwood (Member # 30) on 10-11-1999, 11:38 AM:

I like flat screens for Academy-format and 1.66 films; neither of these formats looks particularly good on a curved screen. For 1.85 films, I'm sort of indifferent. Some look better on flat screens and others look better on shallow-curve screens. For scope, I like both shallow-curve and deep-curve screens (for different reasons), but that assumes that proper curve-screen lenses are used. Scope just looks better to me when shown on a curved screen than a flat screen.

And, yes, I agree with the comments on stadium seating. I really don't like it--short lenses, steep throw angles, and largeish screens are not a good combination.

Posted by Gordon McLeod (Member # 33) on 10-11-1999, 01:47 PM:

In the sixties phillips published a book called designing the cinema that ahd some interesting form ulas for theatre design including the pyscology of the angle of view and screen curvature
They recomended for theatres equiped with 70mm that the screen be curve on a ellipse so that the 1.33 area was flat with only a very slight curve at the edge of 1.66 with a bit more curve at the edge of 1.85 and then the greatest curve to the 70mm format
The grey hammertoned Isco lens sold by phillips were designed for that curve as were the phillips anamophs
The book is well worth reading if you can find an english edition

Posted by Steve Guttag (Member # 268) on 10-16-1999, 08:33 PM:

Ah Curved screens...another one of my specialites...

Curved screens are like any thing that requires skill, they should be done by people qualified to do them, not just anybody. Unfortunately, too many people do them badly and give them a bad name.

All of the complaints I read in this thread are true but correctable/minimized with proper design.

First, the designer should know just WHY they are putting in a curved screen....is it for focus, "wow"-factor, most uniform efficient light, technical...etc....these all have different design criteria.

Once the type of curve is decided upon (throw, shallow curve, deep curve)...then the the design process begins.

If one just takes a matte-white screen and curves it any old way...disaster is bound to creep in.

When one designs the screen...throw, projection angle, gain, seating area must all be factored in because they will affect the final result. I have yet to have curve screens in a plex that the audience preferred the flat screens in the same plex...they are often requested but aren't advertised. The most recent ones I designed were at the Kentland's Stadium 8...two screens were curved...80 lines/mm on ALL targets on RP-40 with 1.85:1 or Scope.

Also, for what its worth...FLAT screens are not distortion free either. Keystoning will still have the buildings leaning in on the edges and with short focal lengths, one can see the myth on the "FLAT FIELD" lenses...they pincushion.

Steve

Posted by Michael Brown (Member # 890) on 07-06-2001, 03:04 PM:

Hi, I just brought this topic up to add my 2 cents worth anyway.

I have to say that I hate curved screens. Mostly because of the distortion and the fact that it makes the aspect ration appear less wide. There is a particular auditorium that I want to rant about that has a 1.85:1 aspect ratio that is presented to look almost square.

Untill a few weeks ago every film I had seen in there was in scope so you just had to suffer through the ads. I ended up watching the flat movie Evolution last weeks and it looked pretty awfull. Plus there was quite a lote of image overlapping onto the masking on the left.

I would also like opinions on a 70mm print of 2001 being shown on a hightly curved Cinerama screen. I think that there were originally cinerama prints of 2001 but the 70mmm print and cinerama screen didnt look too good. The problem was that there was a lot of distortion of angles in the image during many screnes in the movie. To be onist I would have prefered to have seen the print on a flat screen.

Posted by Mark Gulbrandsen (Member # 72) on 07-06-2001, 06:45 PM:

There were very few rectifed 70mm prints made for deep curved screens. Most of the Ultra Panavision films had rectified prints, and Its a Mad mad mad World also did. To my knowledge there were no 70mm rectified prints of 2001.
Mark @ GTS

Posted by Darryl Spicer (Member # 711) on 07-06-2001, 08:07 PM:

I may be wrong about this, but wasn't 2001 shot to utilize the super panavision format. A step down from Ultra panavision. Didn't both the super and ultra panavision 70 prints require some degree of an anamorphic squeeze to them in order to make the picture wider. Ultra having a bit more sqeeze than the super.

Posted by Gordon McLeod (Member # 33) on 07-06-2001, 08:39 PM:

Super Panavision was the same as ToddAo with no squeeze
UltraPanavision/MGM-Camera65 had a squeeze factor

Posted by Mark Gulbrandsen (Member # 72) on 07-06-2001, 09:19 PM:

The rectification that I am speaking about is when they squeezed only the outer sides of the image. This way the image would stretch back to approxamately normal on a deep dish screen. This can be seen on the missing scenes on the (analog) laser disc of I.M.M.M.M.W.

As far as screens go I could go either way. I'll side with Steve G. though on this one that if the deep dish is done right it can look very good. They definately make a film more involving than when shown on a flat screen. Pearl Harbour looked quite good at the Villa which has a near 0 projection angle. Even on the 90 plus foot screen, sharpness was very acceptable as well. Just another tribute to the Phillips DP-70 which they still are using there.
Personally I couldn't imagine either the Villa or Uptown installing a flat screen in place of the curved.
Mark @ GTS

Posted by John Walsh (Member # 168) on 07-06-2001, 11:36 PM:

I'd agree that a curved screen done right looks good. But, it seems that you can't get it done right. The theory is no problem- the problem is things like getting the extra money and getting architects to understand how it should be done (they usually think you are ruining their 'perfect' auditourium design somehow.)

Although, I saw an Omnimax film (Amazon?) at the Hubert H. Humphrey Omnimax Theater in Minneapolis. Sat at the top left of the theater. I was getting a headache from the distortion.

So, I think I would stick with a flat screen, or just a slight curve (2X radius.)

Posted by Jonathan Haglund (Member # 807) on 07-07-2001, 05:31 AM:

One of our theatres has all curved screens with isco-optic lenses to match. Some of the best images I have ever seen. Makes flat screens look downright boring. Though yes, it does take away some of the stunning effect of scope images since the screen doesn't go wall to wall, but I'm not complaining since it just looks so darn good.

Posted by John Pytlak (Member # 331) on 07-07-2001, 08:07 AM:

You need to differentiate between a "deep curved" screen as was used for Cinerama or D-150, and a mildly curved screen designed to optimize light distribution with a gain surface (per SMPTE Recommended Practice RP98). Deep curved screens were intended to envelop the audience with the picture, but had issues like the limited "sweet spot" seating, geometric distortion, and cross-reflections. Mildly curved screens are designed to efficiently reflect light back to the audience, and minimize the "hot spots" and non-uniformity that can occur when installing high gain screens "flat".

------------------
John P. Pytlak, Senior Technical Specialist
Worldwide Technical Services, Entertainment Imaging
Eastman Kodak Company
Research Labs, Building 69, Room 7419
Rochester, New York, 14650-1922 USA
Tel: 716-477-5325 Cell: 716-781-4036 Fax: 716-722-7243
E-Mail: john.pytlak@kodak.com
Web site: http://www.kodak.com/go/motion

Posted by Mitchell Cope (Member # 32) on 07-08-2001, 08:28 PM:

I saw over the weekend a review that the New York Times did on the film "Oklahoma!" when it premiered at the Rivoli in New York City. The review was highly critical of the curved screen used then for Todd-AO and how patrons sitting to the left and right would not be able to enjoy the presentation as those seated in the center. (The review also noted scratches in the presentation and color fluctuation, but I guess that could be another topic.) My point would be, we look back at these things and think these revolutionary (evolutionary?) things like curved screens were well received, when in fact they were not. Widescreen cinematography has certainly survived, but all the components of those initial processes may not have been the best and as well accepted as we think we remember.

Within the last two years, I've seen both "Ben-Hur" and "West Side Story" on a deeply curved screen here in the Kansas City area. In both cases, I think the curved screen took away from the presentation rather than add to it. Maybe it just worked better with Cinerama.

Posted by Scott Norwood (Member # 30) on 07-08-2001, 08:34 PM:

Within the last year and a half, I've seen two 35mm prints of Ben Hur. One was an IB Tech 4-track mag print shown on a flat screen; the other was a relatively recently struck Eastman print shown on a deep-curve screen. I thought that the curved-screen added significantly to the presentation, and I would have loved to have seen the IB print shown on the curved screen.

My own feeling is that most scope films look best on deep-curve or shallow-curve (as opposed to flat) screens, but I do think it depends on the film, and I also can accept that others would feel differently.

Posted by Gordon McLeod (Member # 33) on 07-08-2001, 09:27 PM:

Amazon was not an OmniMax film but and Imax film designed for projection on the curved IMAX screens not a dome
The only 2 OmniFilms I know of are ATMOS and A FREEDOM TO MOVE

Posted by Thomas Hauerslev (Member # 566) on 07-09-2001, 02:31 AM:

More about rectification here

And Dimension 150 here

And finally about Todd-AO distortion printing process here

PS: At home I have made a two feet (2 ft) model of a curved screen (same width as our 25 inch TV). When projecting 70mm films on it, the illusion of being in a large theatre is stunning (provided you sit close enough to it). The curve seems to "suit" the images and they appear more spectacular. Can it be like women? Some find curves more attracting - I certainly do. Flat (screens) are boring.

------------------
Cheers, Thomas
..in70mm - The 70mm Newsletter
www.in70mm.com www.dp70.com www.70mm.dk www.hauerslev.com http://hjem.get2net.dk/in70mm

Posted by John Pytlak (Member # 331) on 07-09-2001, 10:27 AM:

I was fortunate enough to see "How the West Was Won" and "Seven Wonders of the World" projected in original 3-strip Cinerama on a deeply curved strip screen at the New Neon Theatre in Dayton Ohio in April 2000 (John Harvey's wonderful work). I got there early and sat in the "sweet spot". The "wrap around" image added much to the presentation. But if you were unlucky enough to arrive late and get a "bad" seat, there was considerable distortion. John Harvey's 3-projector setup at the New Neon was fairly close to on-axis with the screen. But the high projection angles in some theatres that had significant keystone distortion could look really bad on a deep curved screen, unless the prints were "rectified" (the "Oklahoma" rectified prints).

Gain screens curved for proper light distribution (per SMPTE RP95) have a radius of curvature that rarely is less than 75% of the throw, and so have fewer issues than deep-curve screens.

Posted by Steve Scott (Member # 630) on 07-16-2001, 10:52 PM:

We have 5 curved screens, 13 flat, and I always seem to notice that the flat lenses on our Century SA's won't crop the bottom of the frame as well as they will on the flat screens.
We have all stadium seating, but our curved screens are only in the largest & second largest auditoriums (464 & 264 seats, respectively).
I find the picture in the small houses to be overpowering with our large flat screens, but the curved screens seem to be far away in the rear of the large houses. You feel like you're watching from the ceiling.

Posted by Jeffry L. Johnson (Member # 453) on 07-18-2001, 06:40 PM:

I have a 1980 IMAX booklet that lists the following films as OMNIMAX films.

Voyage to the Outer Planets (1973)
Garden Isle (1973)
Standing Up Country (1973)
Cosmos (1974)
Viva Baja (1975)
Rivers of North America (1976)
Ocean (1977)
Alfa (1978)
Genesis (1979)
Atmos (Storm) (1980)
The Eruption of Mount St. Helens (1980)
Library of Astronomical Phenomena (1980)
The Great Barrier Reef (1980)

In production:

Tomorrow in Space (1982)
Hail Columbia (1982)

Posted by Gordon McLeod (Member # 33) on 07-18-2001, 10:16 PM:

Hail Columbia was released as a flat film with Omni sequences
Some of those other titles were a composite product not looking too good in either format

Posted by William Bunch (Member # 1040) on 11-21-2001, 12:42 AM:

I'm new here so forgive me if this gets into the wrong location.
I am tasked with maintenance of 35 or so military theaters out here in the Pacific. As many of you might know our operations are quite old but they still hum along quite nicely.

My question is concerning the curved screens. All of our frames are curved but only a mild one. I'm assuming this had something to do with the old 20 pound Super Panatar prism anamorphics that we used to employ. Nowdays we are using Schneiders and the majority of our screens are average 15 x 35 feet. Most auditoriums seat 400 - 500
with a couple theaters twice as large.

About six years ago we began being issued silver screens to replace our matte whites. We get good contrast and brightness but that is only for the audience in the middle seats. Our auditoriums are multi use facilities so the seat rows go quite far off of center. Also being multi use these silver screens are prone to gathering handprints, etc.

At ShoWest this last March the Harkness Hall folks said we should not be using silver at all but rather Perlux or matte white. I wonder what the group would have to say about this. I have read through all the earlier postings and can find nothing to disagree with as you all have good points indeed.

Would Perlux give the best features of both matte white and silver?

Bill Bunch
Army, Air Force Exchange Service

Posted by Steve Guttag (Member # 268) on 11-21-2001, 07:06 AM:

The only point to a silver screen is for 3-D....to get even illumination, one has to curve it substantially.

Depending on the curve of your screen, either a matte-white or a perlux (if using Harkness) would indeed be appropriate. If the curve' radius is on the order of the projection distance, then matte-white would be my preference...as the curve increases (shorter radius) then the pearl screen will peform best. To really get the right screen though, one HAS to match up screen-gain with the geometry of the projection and auditorium. People that just pick a screen gain and radius willy nilly, don't know what they are doing.

Steve

------------------
"Old projectionists never die, they just changeover!"

Posted by Richard Fowler (Member # 893) on 11-21-2001, 07:42 AM:

The first good thing are the Panatars are retired so your situations have improved light and better focus. Silver screens should not be used but any pearl gain screen on a mildly curved frame would be better since I assume you have sufficient light output from your lamphouse.Hand prints on silver are a major problem but also less so on pearl since you dealing with another type of coated surface. Schneider Optical with the help of Harkness and Kodak did screen curvature tests to find the ideal situation with current lenses etc; the results of the information are part of the Schneider Lens program which you can download from their site.
Silver has been popular in some Pacific areas such as the cinemas built by the Shaw Brothers and some Golden Harvest but they where designed for the fact that most of the product they where producing and showing was in scope and to boost image brightness from less efficient lamphouses.
Richard Fowler
TVP-Theatre & Video Products Inc. www.tvpmiami.com

Posted by Jerry Chase (Member # 660) on 11-21-2001, 07:49 AM:

Harkness Hall is right. I'd opt for matte white. In a pinch, a matte white screen can be touched up without degrading the image too much.

Other than 3-D, the only time I'd go for a silver screen is in a shotgun auditorium with an undersized lamphouse.

Posted by John Pytlak (Member # 331) on 11-21-2001, 08:01 AM:

Harkness Hall ran a fairly comprehensive study of screen gain and curvature a few years ago, and presented a report at the ITEA Seminar in Los Angeles. Participants included Schneider Optics, Kodak, Lucasfilm, and Famous Players theatres.

SMPTE Recommended Practice RP 95 specifies "Installation of Gain Screens".

The optimal way to determine the proper curve is by ray tracing. The idea is to curve a gain screen such that the projected light is reflected back to the center of the prime seating area.

Very high gain "silver" screens are VERY directional, and as you note, sensitive to handprints, showing seams, etc. Their primary application is polarized 3D projection, which requires a screen that maintains polarization of the reflected light.

For moderate (15 x 35 foot) sized screens, a matte or slight gain surface is the best choice, since getting enough light is usually not an issue.

Here are some links to information:
http://www.bksts.demon.co.uk/articles/jul97.htm
http://www.harknesshall.com/data1.htm
http://www.kodak.com/US/en/motion/newsletters/reel/fall97/screen.shtml
http://www.schneideroptics.com/software/theatre_design_pro/
http://www.schneideroptics.com/info/white_papers/cinema_projection_distortion.pdf

------------------
John P. Pytlak, Senior Technical Specialist
Worldwide Technical Services, Entertainment Imaging
Research Labs, Building 69, Room 7525A
Rochester, New York, 14650-1922 USA
Tel: 716-477-5325 Cell: 716-781-4036 Fax: 716-722-7243
E-Mail: john.pytlak@kodak.com
Web site: http://www.kodak.com/go/motion

Posted by Mark Gulbrandsen (Member # 72) on 11-21-2001, 09:35 AM:

I much prefer the Perlux 2 surface if the budget will support it. Perlux 1 is really made for wrap around type frames and cannot be folded for transport wheras Perlux 1 can be folded into a box(in a special way) and sent by UPS. Its obvious that you have a fairly wide auditorium and a silver screen will never work right in that sort of situation. Silver screens are very directional in their characteristics and will only be best viewed from a limited number of seats in any auditorium. My definate choise for a really large screen that has just a slight curve(which is fine)would be Perlux. You'll have a good compromise on reflectivity vs. seating area with this surface. Perlux is also a fairly long lived surface as well. If you think there might be problems where the screen may get dirty then a matte white is the best choice as it can be cleaned by several methods that all give good results. As far as brand...stick only with Harkness. They make the best surface by far and are a pleasure to do buisness with.

Proper installation of a Harkness screen is imperitive for proper performance of the surface and few people are aware of how this should be done. The top of the screen should be installed with either lacing cord loops all the same size, or black cable ties. The bottom of the screen is then stretched about ten to twelve inches, or to make the top and bottom gap even. Use standard lacing procedures on the bottom but go back and forth a couple of times to stretch it down that much. The sides can be sprung or laced in, what ever you prefer. On curved frames pay close attention to the center of the screen to be sure that it does not belly out from being tensioned too tight on the sides. When the screen is tensioned ten inches to a foot, the seams and any slight wrinkles literally vanish completely and the surface looks to be seamless.
Mark @ GTS

Posted by William Bunch (Member # 1040) on 11-21-2001, 03:33 PM:

In our largest theaters we are using 3kw xenons in LPA lamphouses. The distance to the screen is usually 75 feet. Our really small theaters use the 2kw versions but there the distance is usually around 50-70 feet. None have staduim type slopes and the projectors are on the next floor up. Small angle. Brightness is not usually the problem. Its just the combination of the curve and the silver directing the brightness down the center only. Our curve is very slight. Probably less than two foot difference between center screen and edge. You guys are right. The Perlux would be the way to go for us. Best of both worlds.

Here is a tidbit about how directive silver is. As I stated, we use these auditoriums during the day for other functions besides movies. A commander will assemble the troops for some briefing and use his slide projector to illustrate some topic. When we first switched over to silver the first complaint was "what have you done to the screen?" "We can't see our slides anymore." Well, since their wimpy projectors were setup at chair level all the light was now being reflected up into the border curtains at the top of the stage. If I went into our booth I could see a beautiful bright image but the viewers in the seats would only see a low contrast washed out picture. When I change to Perlux these folks should get most of their picture back.

Thanks everyone for your thoughts on this issue. Have a nice Thanksgiving.

Bill BuncH
AAFES, Japan