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Discussion Starter · #1 ·
I learned something today while out looking at big TV's for my upcoming TH project. I never knew until today that the 16:9 format is not what motion pictures are filmed in. It appears to be its own format that has been selected for wide-screen HDTV.


I found out that if I watch a wide-screen movie on a 16:9 screen that I will either get black lines like a letter box, or I'll get the aspect ratio changed by the set, or part of the picture will be cropped.


This concerned me enough that I had to ask myself if I really need to spend the money on a 16:9 set. To answer this I first opened my spread sheet and made the following tables, one for 4:3, 16:9, and wide-screen 2.35:1 (I know there are other wide-screen formats).


These are my tables:


4:3 Table

A B C

4 3 5.0

21.6 16.2 27.0

25.6 19.2 32.0

28.8 21.6 36.0

34.4 25.8 43.0

40 30 50.0

42.4 31.8 53.0

48.8 36.6 61.0


27.5 20.6 34.3

32.7 24.5 40.9

37.3 27.9 46.6

42.5 31.9 53.1


The Math for 4:3 table.

a^2 + b^2 = c^2

A/B = 4/3

A = 4/3 B

B = 3/4 A

A^2 + (3/4 A)^2 = C^2

A^2 + 9/16 A^2 = C^2

25/16 A^2 = C^2

A^2 = 16/25 C^2

A = (16/25 C^2)^.5


16:9 Table

A B C

16.0 9.0 18.4

28.8 16.2 33.0

34.1 19.2 39.2

38.4 21.6 44.1

45.9 25.8 52.6

53.3 30.0 61.2

56.5 31.8 64.9

65.1 36.6 74.7


36.6 20.6 42.0

43.6 24.5 50.0

49.7 27.9 57.0

56.7 31.9 65.0


The math for 16:9 table.

a^2 + b^2 = c^2

A/B = 16/9

A = 16/9 B

B = 9/16 A

A^2 + (9/16A)^2 = C^2

A^2 + 81/256 A^2 = C^2

337 / 256 A^2 = C^2

A = (256/337 C^2)^.5


2.35:1 Table

A B C

1.0 2.4 2.6

38.1 16.2 41.4

45.1 19.2 49.0

50.8 21.6 55.1

60.6 25.8 65.9

70.5 30.0 76.6

74.7 31.8 81.2

86.0 36.6 93.4


48.4 20.6 52.6

57.6 24.5 62.6

65.7 27.9 71.3

74.9 31.9 81.3


Math for 2.35:1 table.

a^2 + b^2 = c^2

A/B = 2.35

A = 2.35B

B = 1/2.35 A

A^2 + (1/2.35 A)^2 = C^2

1.18 A^2 = C^2

C = (1.18 A^2)^.5


This table spoke volumes to me and confirmed something I noticed in the stores which is that a 40 inch 16:9 did not look much bigger than my 32 inch direct view tv. When I look at a picture I tend to pay more attention to its height then its width so I set up the table to see what the width and diagonal measurement would be for a given height on a standard 4:3 TV. I then also looked at a couple 16:9 sets to find the equivalent 4:3 set.


The one thing that surprised my is that a 16:9 set can chop 24% off the width of a wide-screen movie. (FYI 16:9 is 25% wider that a comparable height 4:3, 2.35:1 wide-screen is about 54% wider than a comparable height 4:3.)


So now I am wondering is the 16:9 thing a fad or is there a solid reason to expect it to be the final HDTV standard? I an leaning toward a 4:3 set that I select by deciding what height picture I want to see in wide-screen format and from there back selecting the listed size. I can use the same method in selecting a 16:9 set too since I will watch mostly movies on my system, some TV (dish), and no games. I am having a hard time justifying the cost of a 16:9 set.


Any thoughts?


Carl
 

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I'm just hoping there won't be a pop quiz later! :p


While there are two basic standards for tv aspect ratios, there are several different standards that directors/producers choose when making films. Some fit better than others and when you can add the overscan built into many TV's, it's no wonder most of us aren't seeing the whole picture. I don't think 16:9 is a fad, it's a dimension that will produce the best widescreen presentation given the variables we have to endure. Also, the 16x9 ratio is pleasing to the eye, aesthetics count.
 

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I can understand the cost issue. 16:9 sets in the US are ( cost wide ) way out of line for what you are getting. So if you are looking for cost effective and you can find an acceptable picture in 4:3 go for it. Remember that whatever set you choose, if it does not have an anamorphic squeese ( v-squeze ) not only are you loosing out on height, you are loosing out on 25% of the resolution of the DVD(anamorphic).


Are 16:9 sets a fad? No.


16:9 recognizes the way the human visual perception works, as well as how movies are generally made. 16:9 is a compromise between 4:3 and 2.35:1. It's also very convienient that many movies are made at 1.85:1. Height is a major concern. Watching a 2.35:1 movie on a 4:3 set yeilds an almost unacceptably small image vs screen size.
 

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I think the statement that the 16x9 screen is a good compromise hit the nail on the head. If you look up the number of films done in each aspect ratio you will see almost twice as many are done in 1.77:1 and 1.85:1( fitting the 16x9 without black bars) than have been done at 2.35:1 and 2.40:1. The 1.35:1 and 2.35:1 fill about 3/4 of the screen and this( along with 1.77:1 and 1.85:1) accounts for the lions share of all films ever made. Just for fun, if you want a laugh, watch letterboxed Ben Hur (2.76:1 aspect ratio) on a 4x3 set. There will be a narrow strip between two enormous black bars. On my 30" set the film is less than 12" tall !

Art
 

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16:9 is the format that was determined to be ideal for HDTV. If you are looking forward to HDTV then a 16:9 set will be what you want.


16:9 (as you found out) isn't the be-all-end-all for movies. Unfortuanlty there are many different aspect ratios.


I was hopnig to go some-where with this...but my mind wandered.


have a good day.
 

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Very complete (free) resource on this particular issue (and others)

http://www.hometheatervillage.com/gu...n_Guide-72.pdf


see particularly Chapter Two: The Father of 16:9


Explains exactly how Kerns Powers came up witht he 16:9 ratio to permit release of a film in any of the various standard wide ratios.
 

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Discussion Starter · #7 ·
Thanks for the input. It confirmed what I suspected. The link to the Father of 16:9 resource was most useful. How do you find thee things? I digress.


To follow my thought one step further I remember sitting in the AVS Science demo theater a year and a half ago with my sister and brother-in-law watching a demo of a projector unit. My brother-in-law was shopping units at the time and I remember a conversation about adding a lens to the projector to get the wide-screen effect. At the time I just listened but now I have to ask, "Will a native 16:9 front projector show a wide-screen movie with black line on top and bottom?"


Based on the information I received while looking at rear projection TV's indicates it would I am bothered by the amorphic lens discussed on this site. What is the need? Or had the need gone away with advances in technology?


I am looking a 16:9 RPTV but would rather have a front projector. Again it is a cost thing.
 

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The anamporphic lens is utilized, in its most simple setup, to utilize the entire panel of a 4:3 projector as opposed to utilizing the full width of the 4:3 panel with only 75 percent of the panel height (when utilizing the 16:9 switch on the projector or scaler).


The trade off is that you use less of the panel during 4:3 material, but since this is usually of less quality, a smaller picture it is a trade off many are willing to make.


The use of the lens is only dubious if you own a 4:3 projector and a 4:3 screen and watch mostly broadcast 4:3 material.



Some are using the 16:9 lenses with 16:9 PJs to obtain a constant height setup with 2.35:1 screens.
 

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Discussion Starter · #9 ·
OK, now that I have the lens issue strait let me ask one more question.


When i was looking at the Toshiba 57HX81 last night I asked if there was a projector that have the same features. I was told by the owner of the shop, who seemed very knowledgeable, that a comparable projector would cost about $7k.


I then asked how a $4K unit he has available would compare and his response surprised me. He said I would need a scaler to match the picture quality and a good screen. I had seen references to scalers before and the response to my last post also mentioned one.


It is true that in order to get a picture with a projector that matches the image quality of a rear projector that I would need a scaler?


What does a scaler give me that is not included in a standard $3-5K projector, or a more expensive one at that? While I like the concept of a projector the costs associated with one seem to be escalating.
 

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Quote:
It is true that in order to get a picture with a projector that matches the image quality of a rear projector that I would need a scaler?
The answer is "it depends".


The more inexpensive projectors out there don't have as good scalers as some of their more expensive bretheren. A scaler is needed to scale the picture from the DVD to the resolution of the projector. Some projectors do a better job at it than others.


I suggest you hang around the Digital projector and Scaler forums for more information.


For the daring (Like myself), you could go with a HTPC. Basically, we use our PCs as scalers and DVD players, among other things. In a lot of cases, we can get superior results this way, and flexibility. The downside is that it requires a lot of work and isn't very user friendly.


Jason
 
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