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Author Topic: A few questions about aspect ratio and 2K vs 4K Bajsic Bojan Expert Film Handler Posts: 190 From: Ljubljana, Si, Eu Registered: Aug 2008 posted 01-23-2013 09:46 AM                     The anamorphic attachment is a non-issue here. You can play the whole flat or scope movie on a flat or scope screen or vice versa, with one lens only and will never crop anything. The picture WILL be letter or pillarboxed, but you will never crop anything. You will never SCALE anything. You will never CROP anything. You will only use the lens ZOOM function. This has nothing to do with an anamorphic attachment which is there for the sake of getting a BRIGHTER image, or a full height scope image in a case when the zoom of a lens is not enough to put both a scope and flat image on a screen with constant height.  |  IP: Logged Antti Nayha Master Film Handler Posts: 268 From: Helsinki, Finland Registered: Oct 2008 posted 01-23-2013 10:28 AM                     ^ What Bajsic said. Nastia, you’re being confused by the fact that the anamorphic lens does stretch the image optically… But the important part is this: the picture is digitally stretched in the other direction before it hits the anamorphic lens to compensate for the distortion! Because of this, the end result is geometrically identical to a zoom lens solution. A 2.39:1 picture will always be 2.39:1 on the screen, regardless of whether you’re using an anamorphic lens or not.  |  IP: Logged Nastia Motovilova Film Handler Posts: 30 From: Nicosia, Nicosia, Cyprus Registered: Sep 2012 posted 01-26-2013 02:51 AM                    About the aspect ratio, in Brad's post here, http://www.film-tech.com/cgi-bin/ubb/f16/t000669/p4.html If you run a scope movie in flat, you then see the black bars AND you still crop off the sides. In other words, flat doesn't use the entire width of the chip and scope doesn't use the entire height. I thought when showing a scope film in a flat screen, you only get the letterbox effect, but not both the letterbox and pillar box. I have experienced this in a cinema, where there is top-bottom and side black bars, but when does this actually happen? Thanks for the replies.  |  IP: Logged Bajsic Bojan Expert Film Handler Posts: 190 From: Ljubljana, Si, Eu Registered: Aug 2008 posted 01-26-2013 03:24 AM                     you will not get pillarbox (that is black bars on the side) when showing a scope inside flat. but since flat uses 1998 px, and scope uses 2048 px, you will be cutting 50px of the scope image.  |  IP: Logged Marco Giustini Film God Posts: 2713 From: Reading, UK Registered: Nov 2007 posted 01-26-2013 06:09 AM                     Nastia: One thing is "showing Scope in Flat". Another is "showing Scope on Flat screen" - but using a Scope function. You can indeed show a scope on a Flat screen having bars on top and bottom only. But you won't be using a Flat Macro, which is set for 1998 rather than 2048. If you show Scope on a Flat screen, filling the entire screen, you'll end up cropping a huge part of the active picture.  |  IP: Logged Bajsic Bojan Expert Film Handler Posts: 190 From: Ljubljana, Si, Eu Registered: Aug 2008 posted 01-26-2013 11:18 AM                     here's pictores i's mades (since they cannot be shown unless somebody gets mad, just click on them): 185 scenario 239 scenario hope its useful and you will better understand. Others can just admire my MSpaint skills.  |  IP: Logged Manny Knowles "What are these things and WHY are they BLUE???" Posts: 4247 From: Bloomington, IN, USA Registered: Feb 2002 posted 01-26-2013 11:42 AM                     Is it just me, or do those images seem mixed up somehow?  |  IP: Logged Dave Macaulay Film God Posts: 2321 From: Toronto, Canada Registered: Apr 2001 posted 01-26-2013 12:33 PM                     Regardless of mixup, there's an error in a caption on one of the "185 scenario" images. This shows scope on a flat screen using the flat macro, saying "no masking". Wrong. The image is masked at left and right edges, removing 50 pixels (25 per side). it's a small difference but visible if you look at the man's elbow area. Do whatever you want, there won't be any DCI police squad giving you the rubber hose treatment because you violated their rules. There is quite a bit of debate about what's best: I think that the ideal is a screen physically masked to the correct ratios and electronic masking adjusted to the format limits. Whether you have a scope ratio screen masked down to flat, or a flat screen masked to scope... doesn't much matter. The original idea of Scope was "bigger wider screen" and some think the scope screen should always be bigger. With stadium big-screen cinemas I don't think it matters. In recent 35mm film projection (recent being after 1.33 films disappeared in North America), 1.85 used a smaller film image area and could look pretty weak on a huge screen, scope used a lot more film image area and could look pretty nice on a big wide screen. Digital projection reverses that, the scope image has fewer pixels (-18%) than the flat image. So projecting scope inside a flat screen preserves the image resolution (infinitesimally improves it if you zoom back to use the extra 50 pixel width, but of course there's still less image on screen overall compared to flat). Using an external anamorphic lens restores the scope image to slightly higher pixel count than flat (+2.5%) but this is a very rare solution, hardly any venues are willing to pay the anamorphic accessory lens cost. Once again, do whatever you want. It's not likely anyone will complain (nobody usually complains about even incredibly bad presentation in my experience). If you want to crop scope to fill a flat screen, no problem. My instinct is that people don't complain, but they don't come back. Venues with bad presentations where there's competition with a better product within easy travel will not prosper. Doing projection "right" won't make an immediate difference in patronage but it will over time steer a lot of people to prefer your cinema over a bad one. Putting on a crap presentation will steer them to your competition. I know people in an isolated town who will drive 4 hours to "the city" to see a blockbuster film rather than go to the (fair-poor image and mono sound) local cinema. They still take their kids to the local though, and teens don't have much choice. The local is finally installing stereo sound (5.1 even!) and "going digital" but it may take years to get people that care about presentation to come back through their door.  |  IP: Logged Bajsic Bojan Expert Film Handler Posts: 190 From: Ljubljana, Si, Eu Registered: Aug 2008 posted 01-26-2013 12:34 PM                     ok, i see how they could be misinterpreted. i changed the naming now. Since the point is to show two different movies, it would not be the point to show images from the same movie, right? 1.85 screen (constant width) 2.39 screen (constant height) @Dave: quote: egardless of mixup, there's an error in a caption on one of the "185 scenario" images. This shows scope on a flat screen using the flat macro, saying "no masking". Wrong. The image is masked at left and right edges, removing 50 pixels (25 per side). it's a small difference but visible if you look at the man's elbow area. Yes, I do mention the cropping of the 50 px. It is in the lines directly below the nomasking comment. I was implying there is no masking used in the representation. Well, i fixed that. And yes, i agree with all the aspects you mentioned. The scenarios I show on the RIGHT side of the pictures are nonDCI compliant and completely WRONG ways to present movies. Which reminds me, why didnt i put that in before edited.  |  IP: Logged Nastia Motovilova Film Handler Posts: 30 From: Nicosia, Nicosia, Cyprus Registered: Sep 2012 posted 01-26-2013 04:45 PM                    Thanks for that practical example Bajsic! Much much clearer now. So this quote: Bajsic Bojan Projecting a 1.85 film filling a 2.39 screen, you are cropping (as in, deleting, loosing, not showing) 20,6% of the image height. refers to the top right screenshot of the 2.39 link scenario whereas this quote: Bajsic Bojan Projecting a 2.39 film filling a 1.85 screen, you are cropping 22,8% of the image width. refers to the bottom right of the 1.85 link scenario. A few more questions to understand this better, With which settings will we get a letterbox and pillarbox effect at the same time? And if we were to use an anamorphic lens to avoid the pillarbox effect, would we get the same quality as when projecting a 2.39 film on a 2.39 screen? Or do we get even in the best of circumstances deterioration of the picture quality? (Is the main conclusion that in the end, anamorphic will be used when we have an issue of wanting to increase brightness?) Thanks for all the replies!  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 01-26-2013 04:47 PM                     Bajsic - forum rules require you to upload images direct to this server for display on the forum discussion pages, not link externally (which kills the archives for the future). You need to do this immediately.  |  IP: Logged Bajsic Bojan Expert Film Handler Posts: 190 From: Ljubljana, Si, Eu Registered: Aug 2008 posted 01-27-2013 01:14 AM                     Yes. i wanted to do that, well here they are. Can you please delete the old links to the outside picture sharing site? (I cannot do that with the edit function) 1.85 common width screen: 2.39 common height screen:  |  IP: Logged

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