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There may not be a better example of group-think ;). This is presently called the “2.35:1 CIH” forum, yet movies in the 2.35:1 aspect ratio went out in about 1971 and 2.39:1 or the more industry-accepted “2.4:1” is the actual aspect ratio of UltraWide movies ever since. Every day at Panamorph we advise movie enthusiasts asking about 2.35:1 to actually order a 2.4:1 screen as a better fit when using our lenses (or even when not). Sure, it’s not that big of a difference and you’re probably overscanning a bit onto the screen border for other reasons as well. It’s only 32 horizontal pixels lost on each side from a 4K (specifically UHD/3840) projector. But if there’s no additional cost then why not be accurate? Where did this come from?

Group think – I think. This 2.35:1 CIH forum has been around for about 13 years in a niche that is still only touching the surface of the market (“why” and future evolutions being a topic for another discussion). That’s actually a long time for an expression to sink in when there are actually very few other resources out there. And as a niche that forum title has significant authority when most people are coming here to learn. But why or where did it start in the first place? My inclination is to suggest IMDB.com. It’s seems like almost any time a new UltraWide movie comes out IMDB lists the aspect ratio as 2.35:1. IMDB was around during the start of the AVS Forum as one of the few reference databases out there. A classic example? In the early AVSF days the Leeloo jump shot from The Fifth Element was used almost as a reference image. Go to IMDB and the aspect ratio is shown as “2.35:1”. The movie was actually filmed at 2.39:1 – the industry standard. This inconsistency is very consistent throughout IMDB.com for most UltraWide movies – about 80% of the most popular movies made, and may be a primary reason “2.35:1” ended up in the forum title those many years ago. Why not trust the largest and most referenced movie database?

Unfortunately this has spawned the classic group think phenomenon. When I ask others in our own industry why they say “2.35:1” instead of “2.4:1”, when just about everybody in the industry knows the difference, they say it’s because they don’t want to confuse people who are already thinking about “2.35:1”. They’re actually reinforcing the issue.

Is this forum the actual source for today’s home theater (cinema) enthusiasts and perhaps the entire industry using the “2.35:1” phrase? If so then perhaps we should request the powers that be to consider changing the forum title so that we can get everybody on the same page where the width is both simply and exactly 12/5 times the height and 12/13 times the diagonal.

And yes, I’ve started the outreach to IMDB.com to ask them to update their tech specs.

For now though, if you are thinking of creating your own cinema format theater, please consider ordering a 2.4:1 screen rather than 2.35:1. On a 4K/UHD projector with an anamorphic lens that’s around 100,000+ more pixels on your screen you’ll get for free.
 

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I wrote an article about the difference between 2.35:1 and 2.40:1 a few years back:

https://www.highdefdigest.com/blog/constant-image-height-refresher-2013-part2/

The continued inaccurate use of the phrase "2.35:1" when talking about movies that are actually 2.3942:1 (and later 2.3912:1) stems back much further than the existence of this forum or IMDb. Many people in the film industry are creative types, not engineers, and kept saying "2.35:1" even after the technical specs for the format changed in 1970. That phrase simply stuck, despite being mathematically inaccurate.

Although the theatrical standard for scope projection has been some variation of 2.39 and change for almost 50 years, even today there is little consistency in how those movies wind up transferred to home video. I own a number of Blu-rays that are authored on disc as 2.35:1 even though the movie was made well after the switchover. A recent example is The Man Who Fell to Earth, produced in 1976. The movie was scanned in 4k for a theatrical re-release in 2016 and issued on Blu-ray by Lionsgate earlier this year. The active image area in the Blu-ray transfer is 1920x818 pixels, for a ratio of 2.347:1.

If the movie was shot on film, the aspect ratio of the video master is dependent on the calibration of the telecine used for the scan. A scope movie can easily wind up anywhere from 2.30:1 to 2.40:1, regardless of the theatrical standard.

The Blu-ray release of Spectre (a 2015 film!) has an active image of 1920x804 pixels, or 2.388:1. I can think of no technical reason why that happened. It just did. The 2016 "Director's Cut" Blu-ray of Star Trek II: The Wrath of Khan (new 4k master at that time) is the same, 1920x804. These are discs from two different studios, MGM and Paramount respectively. Other Blu-rays of movies made in these same eras are 1920x800 (a precise 2.4:1). Why aren't these two? Who knows?

In my opinion, there's little sense fretting over this too much. No matter which ratio screen you install in your home theater, you'll wind up with a good portion of movies that don't fill it precisely. You'll either get tiny letterbox bars when a 2.40:1 transfer is projected onto a 2.35:1 screen, or tiny pillarbox bars when a 2.35:1 transfer is projected onto a 2.40:1 screen.

For that matter, if you use an anamorphic lens with a 1.33x stretch in front of a 1.78:1 projector, the actual projected image is 2.37:1, which is neither here nor there. The lens will also add some pincushion distortion of the ratio as well.

If the small black bars are a concern, you can easily zoom the image out a little and let a sliver of picture fall off the screen without harming the compositional intent of the photography in any noticeable way. Any of these ratios is within the tolerance of expected variances in theatrical projection. Cinematographers account for this during filming. During the analog TV era, televisions typically had 10% or more overscan cropping of the image. To this day, every motion picture camera viewfinder has "TV Safe" markings that tell the DP to keep important picture content away from the extreme edges of the frame.

I have a 2.35:1 screen in my home theater because that was the standard size being offered by the screen manufacturer when I ordered. I've never had any issues with it or regretted not getting 2.40:1.

The visible difference between any of these ratios is so small that, at a certain point, "close enough" simply has to be good enough. You'll never get perfection across 100% of the content you watch, because the people creating that content aren't consistent in how it winds up transferred to video. Many of them may not even be aware that there is a difference at all.
 

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Discussion Starter #3
Thanks Josh. I agree that it's a small difference; some overscan is going to be part of the setup in any case; and certainly that difference won't compromise the content itself. But if there is a choice between 2.4:1 and 2.35:1 and there's no cost difference then it still seems like 2.4:1 should be the screen choice for most films. It's true that a 1.33x stretch of 1.78 is 2.37:1 but in reality it's the movie itself that we typically want to fill the screen rather than the full projector res. A 1.33x stretch makes a 3840x1600 2.4:1 movie leave black slivers top and bottom. So when you zoom too fill the height of a 2.35:1 screen with most movies you're overscanning onto the side borders. I do say "most" movies however and realize that the actual AR can be all over the "UltraWide" map. I'm just thinking that we might as well aim for the center of the map.

As a counter to my own argument, our Paladin lens allows an adjustable aspect ratio so you can actually make 2.4:1 movies fit 2.35:1 screens so yeah - nothing to fret about but kind of just trying to go for a "best practice" if someone is looking at getting a new screen.
 

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nothing to fret about but kind of just trying to go for a "best practice" if someone is looking at getting a new screen.
I get that, but I have seen a lot of people in this forum gnashing their teeth over this decision when, in practical terms, it really doesn't make much of a difference. Either way, you're going to have to deal with some tiny black bars. And either way, zooming up a smidge takes care of it.
 

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Discussion Starter #5
Well, I'm all for avoiding the teeth-gnashing :). The industry has been making great strides in the past few years to make the cinema experience (including anamorphic) easier to get in the home so hopefully this all leads to expanding the niche.
 

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2.35:1 or "235" as it more commonly called is just a name now. Just like the new term 21:9 is not correct as well as that is closer to 2.33:1. That is why I use "Scope" or "Ultra Wide" to describe this exciting format.
 

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Just to demonstrate how common the confusion between these aspect ratios is and how the studios (even conscientious labels) continue to treat them as indistinguishable, the new Criterion Collection Blu-ray for Election has an active image area of 1920x818 pixels, or 2.347:1. The movie was made in 1999, almost three decades after the theatrical standard switched to 2.39:1. The Blu-ray also comes from a brand new 4k scan supervised by director Alexander Payne and Criterion's technical director, Lee Kline. If these two guys didn't notice that the aspect ratio is off, how can we expect anyone else to?

Interestingly, the older Blu-ray edition from Paramount has the exact same image area of 1920x818 pixels even though it's definitely a completely different scan.
 

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Interesting thread. This subject comes up in the screens forum from time to time. Back in the day, we were considering a replacement scope screen. I started talking to the Da-Lite rep about possible ARs. FWIW, they will make any size you want (within reason). We were going to settle on a 2.37:1 to in fact "split the difference" between 2.35 and 2.40. Then they stopped making HP screens:(
We waited a year or two, while they promised to start making them again. By the time they finally pulled the plug, my OCD had calmed down and we bought an "off the shelf" 2.35:1 from Elite.
Bottom line, is what Josh said: No matter what size you get you will end up having to play around with you lens controls to get the image centered in the screen area. That's what the black masking on the edges are for;)
Film directors are creative individuals. Probably hard to get them to agree on any "universal" format.
Here is a thought. In this day and age of electronic controls, how come some one like Lumagen can't make a device that manipulates the image and "automatically" fills what ever screen you have? Our Sharp Z30K has lens memory, but it's only acurate to 2%. When we change screen ARs, it gets "in the ballpark" with the push of one button. Then, it takes manual tweaking to get everything lined up. I get it that everyone's set up is different. However, how about a gadget where you enter your screen AR ONE TIME and it senses what ever image size is fed to it and outputs the correct AR to fill your screen? I would buy one:)
 

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Discussion Starter #10
There are certainly now and probably always will be slight variances in movie aspect ratio, whether intentional or not. There will also be the more rare multi-aspect movies (eg. C. Nolan) and there will also be rare non-standard ratios (eg Jurassic World).

Here's all I'm proposing: If you are getting a new screen for your home theater made primarily for the popular movies made in the past 50 years then 2.4:1 is the best fit for most of them and there's really no cost difference between 2.4:1 and 2.35:1. But I certainly agree with Josh - if you already have a 2.35:1 screen then that's so close to 2.4:1 and may even perfectly fit some of the other movies that it's not worth changing.
 

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Interesting thread. This subject comes up in the screens forum from time to time. Back in the day, we were considering a replacement scope screen. I started talking to the Da-Lite rep about possible ARs. FWIW, they will make any size you want (within reason). We were going to settle on a 2.37:1 to in fact "split the difference" between 2.35 and 2.40. Then they stopped making HP screens:(
We waited a year or two, while they promised to start making them again. By the time they finally pulled the plug, my OCD had calmed down and we bought an "off the shelf" 2.35:1 from Elite.
Bottom line, is what Josh said: No matter what size you get you will end up having to play around with you lens controls to get the image centered in the screen area. That's what the black masking on the edges are for;)
Film directors are creative individuals. Probably hard to get them to agree on any "universal" format.
Here is a thought. In this day and age of electronic controls, how come some one like Lumagen can't make a device that manipulates the image and "automatically" fills what ever screen you have? Our Sharp Z30K has lens memory, but it's only acurate to 2%. When we change screen ARs, it gets "in the ballpark" with the push of one button. Then, it takes manual tweaking to get everything lined up. I get it that everyone's set up is different. However, how about a gadget where you enter your screen AR ONE TIME and it senses what ever image size is fed to it and outputs the correct AR to fill your screen? I would buy one:)
I think in general there wouldn't be that much of a market for such a device because while there may be aspect ratio variations, like Josh said, they are really small and easily masked by the screen border. At least one thing that is constant is that all the UltraWide movies fill the width of the screen (at least they are supposed to) - it's just the height of the content that varies and for the vast majority of UltraWide movies they never go beyond 2.4:1, which means they (again, vast majority) never go shorter than a 2.4:1 screen. So if you have a 2.4:1 screen then the rare movie that has a slightly lower AR just gets masked off at the top and bottom.
 

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I think in general there wouldn't be that much of a market for such a device because while there may be aspect ratio variations, like Josh said, they are really small and easily masked by the screen border. At least one thing that is constant is that all the UltraWide movies fill the width of the screen (at least they are supposed to) - it's just the height of the content that varies and for the vast majority of UltraWide movies they never go beyond 2.4:1, which means they (again, vast majority) never go shorter than a 2.4:1 screen. So if you have a 2.4:1 screen then the rare movie that has a slightly lower AR just gets masked off at the top and bottom.
I was inspired by Craig here and now have multiple AR screens. So, we are constantly switching between 16x9 (which BTW seems to be pretty "standard" size) and our 2.35:1 scope screen (size all over the map). Thus, I am continuously playing around with the lens controls to get a "perfect" fit.
Here at AVS, OCD is almost a normal state of mind. I'll bet that many (if not most) AVSers adjust their images to minimize overscan and maximize image AR.
A device to do it automatically would be a big seller, at least here;)
 

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I’m having a bezel free 2.4:1 screen built to replace a silver ticket 2.35 curved screen. I had a time figuring out why I could never make the image fit the screen till I realized my A lens was designed to do a 2.4 stretch so I always had overscan on the sides or bars on top and bottom. Just a little and no biggie when watching movies but I use my pc as the source 99% of the time so I noticed it a lot.


Sent from my iPhone using Tapatalk
 

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Just to demonstrate how common the confusion between these aspect ratios is and how the studios (even conscientious labels) continue to treat them as indistinguishable, the new Criterion Collection Blu-ray for Election has an active image area of 1920x818 pixels, or 2.347:1. The movie was made in 1999, almost three decades after the theatrical standard switched to 2.39:1. The Blu-ray also comes from a brand new 4k scan supervised by director Alexander Payne and Criterion's technical director, Lee Kline. If these two guys didn't notice that the aspect ratio is off, how can we expect anyone else to?

Interestingly, the older Blu-ray edition from Paramount has the exact same image area of 1920x818 pixels even though it's definitely a completely different scan.
Does this this have anything to do with it being scanned at 2K/4K being 2048/4096 Vs HD's 1920 or UHD's 3840?

I ask because I remember some discussion around ALIEN on BD and how it was scanned in at either 2048 or 4096, then cut back to 1920 for HD. This has to change the AR, but after scaling for CIH, I don't see this because the display remaps the center 810 pixels over the available 1080.
 

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I’m having a bezel free 2.4:1 screen built to replace a silver ticket 2.35 curved screen. I had a time figuring out why I could never make the image fit the screen till I realized my A lens was designed to do a 2.4 stretch so I always had overscan on the sides or bars on top and bottom. Just a little and no biggie when watching movies but I use my pc as the source 99% of the time so I noticed it a lot.


Sent from my iPhone using Tapatalk
Ideally the anamorphic should be designed on a 1.33x expansion but Throw Ratio and actual distance also affect the outcome due to Grid Distortion.

On shorter TRs, a 1.33x adaptor can give an AR out to 2.45:1.
 

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Ideally the anamorphic should be designed on a 1.33x expansion but Throw Ratio and actual distance also affect the outcome due to Grid Distortion.



On shorter TRs, a 1.33x adaptor can give an AR out to 2.45:1.


You know that’s probably part of it. I Remember them mentioning on these forums that they intended for the user to utilize a little bit of overscan because someone had asked why have a 2.4 adapter when screens are 2.35.

However my throw ratio is around 1.4 so I fight distortion worse and it wouldn’t surprise me if it had stretched my aspect ratio as well. I was curious about doing a 2.76 screen because most of the stuff I do is on the PC and I can do a custom resolution easily, and then it would truly be constant image height even for movies like Ben Hur or the hateful eight but I could only get this material so long and to do that I would be sacrificing a lot of height.


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Does this this have anything to do with it being scanned at 2K/4K being 2048/4096 Vs HD's 1920 or UHD's 3840?

I ask because I remember some discussion around ALIEN on BD and how it was scanned in at either 2048 or 4096, then cut back to 1920 for HD. This has to change the AR, but after scaling for CIH, I don't see this because the display remaps the center 810 pixels over the available 1080.
I don't think that's it. The 4k scanner has a resolution of 4096x2160, to match the DCI standard. UltraHD video is 3840x2160. The difference between these is that DCI has a 1.9:1 ratio while UHD is 1.78:1. In either case, a scope movie is letterboxed within it.

In order to get the 4096x2160 image into a 3840x2160 container, there are two options: 1) Scale it down and preserve the entire visible image, adding extra letterbox bars on top and bottom, or 2) Crop it and lose some image.

Whoever did the transfer on Alien opted to crop. They chopped 128 pixels off each side. Then, because that left the image with an aspect ratio of about 2.25:1, they also cropped 53 pixels off each the top and bottom. Therefore, even though the image has a 2.40:1 aspect ratio, it's actually missing picture on all four sides. Then they scaled that down to 1920x1080 for Blu-ray.

In deciding to do that, they could have just as easily chosen to crop to 2.35:1 rather than 2.40:1. Perhaps that's what happened with Election, but I think the target ratio was probably determined irrespective of whether the scanning would be done at 4k, 2k, or 1080p.

The process probably went something like this:

Transfer technician: "You shot this in Super 35. What's the aspect ratio supposed to be?"
Alexander Payne: "It's a two-three-five movie."
Transfer technician: "OK, thanks. That'll do."
[Technician punches in 2.35 on console and no one gives any further thought to it.]
 
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I don't think that's it. The 4k scanner has a resolution of 4096x2160, to match the DCI standard. UltraHD video is 3840x2160. The difference between these is that DCI has a 1.9:1 ratio while UHD is 1.78:1. In either case, a scope movie is letterboxed within it.

In order to get the 4096x2160 image into a 3840x2160 container, there are two options: 1) Scale it down and preserve the entire visible image, adding extra letterbox bars on top and bottom, or 2) Crop it and lose some image.
This is what I was wanting to know.

4096 / 2.39 = 1714
3840 / 2.39 = 1606

At 1080, that is still 48 pixel differences in height.

The comments on ALIEN was that the frame felt cramped.
 

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This is what I was wanting to know.

4096 / 2.39 = 1714
3840 / 2.39 = 1606

At 1080, that is still 48 pixel differences in height.

The comments on ALIEN was that the frame felt cramped.
As I mentioned, Alien is cropped on all four sides in order to maintain the 2.40:1 ratio of width to height. Essentially, the picture is zoomed in a little.
 
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