How much are true IMAX films cropped by to fit onto digital screens (and vice versa)?

[hakunamufasa]

I've never seen a true IMAX film in the 70mm format, unfortunately (none near to me), but I know from experience with digital IMAX that their screens are more of a 'widescreen' affair compared to the 'real' IMAX's square, 4:3-type aspect ratio (I don't know much about aspect ratios, forgive me; I know that 4:3 is standard, that 16:9 is widescreen and that it relates to width/height of the image). When native IMAX films are converted for IMAX digital theatres, by how much are they cropped?
I found a picture to show what I'm talking about:

Also, are IMAX-converted films (e.g. Guardians of the Galaxy) cropped in order to fit the 70mm screens? Cropping the tops of 70mm for digital showings isn't too bad (as you can see with the Dark Knight you don't miss too much detail, but that was filmed in a certain way to suit the nature of filming with IMAX cameras), but wouldn't cropping the sides of the DMR to make it suitable for 70mm showings lose you quite a bit more detail (remember the letterbox/pan-and-scan DVDs?) as can be seen below with LOTR (I know that it wasn't filmed in IMAX; I'm using it as an example of the cropping in general).

I'm asking the second question b/c of a statement I found on Wikipedia on a page entitled 'List of IMAX DMR films' (obviously not the best but the only place I could find clear info on whether 70mm screens show DMR films or not):
"However, since 2002, some feature films shot with digital cameras or on regular 35mm film stock have undergone IMAX Digital Media Remastering (DMR) processing for showing both in 70mm IMAX theatres and in Digital IMAX theatres."

[singhcr]

That is an interesting question you've brought up. Normally, a movie is cropped from a wider image to a narrower one but with IMAX it is the other way around.

Aspect ratio is the ratio of width to height. A perfect square would be 1:1. Your standard HDTV is 16:9, or if you divide 16 by 9 you get 1.78 so the actual aspect ratio is 1.78:1. Basically, an HDTV picture is almost twice as wide as it is tall.

IMAX film has an aspect ratio of 1.44:1, slightly wider than the old TV ratio of 1.33:1. Most epic movies are 2.40:1, so an IMAX filmed image would have to be cropped by roughly 42% to fit the 2.40:1 frame. In the case of the Dark Knight, the cinematographer would make sure that the area that would be shown in a standard theater (i.e. 2.40:1 widescreen) would be framed nicely and not lose any parts of the image that are important to the story. This is called a protected zone, as you are shooting an image with the knowledge that parts of it will be cropped out.


The answer to your question is no. Interstellar is coming out in IMAX 70mm today, and it has a mix of 2.40:1 35mm material and 70mm IMAX. The entire screen will be used for the IMAX footage, but the rest of the movie will be letterboxed so none of the image is cropped off.

[hakunamufasa]

Originally Posted by singhcr

The answer to your question is no. Interstellar is coming out in IMAX 70mm today, and it has a mix of 2.40:1 35mm material and 70mm IMAX. The entire screen will be used for the IMAX footage, but the rest of the movie will be letterboxed so none of the image is cropped off.

I know that, but I'm talking about films that aren't filmed with IMAX cameras for their entirety (e.g. 35mm for the entirety of the film but that've been DMR'ed). Some films such as Guardians of the Galaxy did change aspect ratios throughout the IMAX 3D version (http://www.ropeofsilicon.com/guardia...atios-imax-3d/), but what about the stuff such as The Lion King (shown in IMAX in 2002) that doesn't shift aspect ratios? They aren't shown as normal with the black bars at the top and bottom; that wouldn't be an IMAX presentation if it was normal throughout.

Thanks for the info though and the protected zone info; didn't know that the area had a name even though I knew about the area itself.

[hakunamufasa]

In relation to the last post I made, The Lion King's aspect ratio is 1:66:1 and the 70mm IMAX is 1:43:1, so it wouldn't have ruined the picture too much by compressing the size of the image. IMAX only developed their digital projection system of 1.89:1 or 2.39:1 (whether this depends on the film or screen, I'm not too sure) in 2008, a full 6 years after the Lion King's IMAX run. Even from 1:89:1 (DMR/non-IMAX film) to 1:43:1 (70mm IMAX format) there probably isn't much of a difference, not like below anyway with 2:39:1 (standard to 70mm) :


That Tron picture above could be the answer.

GOTG was similar to above (2:35:1 instead of 2:39:1, but similar enough); I definitely remember the screen changing before the film was about to start and also with Godzilla and TASM2, the other two IMAX films I saw this year. Now that I've looked into it more (Godzilla and TASM2 were also 2:35:1) I'm sure it happens with most non-native IMAX films but we don't notice as the *bars blend into the darkness of the walls of the room.

*bars meaning dead space

My conclusion is that the same happens with showing standard films on 70mm and digital IMAX screens and that there are bars there, but that you don't notice them.

[singhcr]

Originally Posted by hakunamufasa

I know that, but I'm talking about films that aren't filmed with IMAX cameras for their entirety (e.g. 35mm for the entirety of the film but that've been DMR'ed). Some films such as Guardians of the Galaxy did change aspect ratios throughout the IMAX 3D version (http://www.ropeofsilicon.com/guardia...atios-imax-3d/), but what about the stuff such as The Lion King (shown in IMAX in 2002) that doesn't shift aspect ratios? They aren't shown as normal with the black bars at the top and bottom; that wouldn't be an IMAX presentation if it was normal throughout.

Thanks for the info though and the protected zone info; didn't know that the area had a name even though I knew about the area itself.

You're welcome!

For movies that have no IMAX footage, they are usually presented in their original aspect ratio (OAR). Sometimes you have different approaches like Avatar being 1.78:1 in IMAX and in digital 3D but 2.40:1 for 2D theaters. Skyfall's OAR is 2.40:1 but it was opened up to 2.00:1 for IMAX. In that case, there was a lot of extra space on the top and bottom of the frame that made all the shots look loosely framed. It's termed "dead space."

I'm not sure what you mean by an "IMAX presentation", though. It all depends on the movie, but the typical approach is to show non-IMAX filmed content in its OAR, regardless of whether the movie is entirely non-IMAX sourced or if it is a hybrid. Many different kinds of movies are shown in IMAX 70mm and most have no IMAX footage whatsoever, and the few that do have it for select scenes.

[hakunamufasa]

Originally Posted by singhcr

I'm not sure what you mean by an "IMAX presentation", though.

Full-screen w/no dead space.

For movies that have no IMAX footage, they are usually presented in their original aspect ratio (OAR).

Thanks for the info; this is likely to be the answer as in every IMAX screening I've been in the aspect ratio changes after the ads/trailers are shown. I came to a similar conclusion in the post w/the Tron picture.

[jscoggins]

[hajiketobu]

I did this graphic for the aspect ratios of Interstellar. I think this gives you a good overview of the different formats.


I don't know about home cinema releases of imax movies, i think every director does it differently, but i would prefer a version that switches between 16:9 and 2,40:1 on one blu-ray and a version of the original aspect ratios on a second blu-ray.

[ZoetMB]

Good graphic, but it assumes constant width for all ARs, which is usually the case these days, but not always and it also assumes that the screen width is the same for all formats, which is definitely not true.

And I heard that at the new IMAX installation at the TCL (originally Graumann's) Chinese Theatre in Hollywood, even though they're showing Interstellar in 70mm IMAX and even though they're claiming it's the largest IMAX theatre in the world (although I think they might be referring to the number of seats or the square footage of the auditorium and not the screen size), it's still only going to be 1.9:1 and not the proper 1.4:1. I challenged the person who presented that info, but he swears it's correct. If that's accurate, it must be that the theatre wasn't tall enough, even though that's a very large theatre. There's a YouTube video of the theatre reconstruction.

TCL Chinese Theatre IMAX Renovation - Time Lapse Video - YouTube

[jscoggins]

The Grauman IMAX is largest in terms of seating but not screen size.

http://en.wikipedia.org/wiki/IMAX

http://en.wikipedia.org/wiki/TCL_Chinese_Theatre

By the way, how else would you compare the aspect ratios other than constant width? It makes no sense to compare constant height since the IMAX presentations (15/70 or Digital) go taller, not wider.

[WJWS Channel 13:Amity]

Originally Posted by ZoetMB

And I heard that at the new IMAX installation at the TCL (originally Graumann's) Chinese Theatre in Hollywood, even though they're showing Interstellar in 70mm IMAX and even though they're claiming it's the largest IMAX theatre in the world (although I think they might be referring to the number of seats or the square footage of the auditorium and not the screen size), it's still only going to be 1.9:1 and not the proper 1.4:1. I challenged the person who presented that info, but he swears it's correct. If that's accurate, it must be that the theatre wasn't tall enough, even though that's a very large theatre. There's a YouTube video of the theatre reconstruction.

TCL Chinese Theatre IMAX Renovation - Time Lapse Video - YouTube

Umm yeah not true!!!
We are projecting in 1.4:1 and we have masking in place on the sides as we did last year with Wizard of OZ IMAX 3D(digital) last year and Maginifcent Desolation Walking on the moon(70mm)