|   TV Aspect Ratios??? | 4runner58
Jul 6, 2001 4:00 PM | | Is a standard off the shelf tube TV a 4:3? I assume this means the horizontal is 4 units long and the vertical is 3 units tall. I have seen a 16:9 in a store (might have been rear projection) and the salesperson also mentioned another ratio (maybe 15 by something?) Are there only two or are there three....or more ratios?
Is "letterbox" a 16:9 ratio?
Why do some TVs - all 4:3 - show less (or more) black band at the top and bottom of the screen than others - when choosing "letterbox" or 16:9 format? When I go to the store and look at a row of "same size" TVs all showing the same movie at the same time, there is a drastic difference in the black bands.
Do different DVD movies have different mappings of 16:9 onto a 4:3 tube? I think I have noticed a difference in black band width on my TV when switching from one DVD movie to another - both displaying in 16:9 format.
Also, what is anamorphic squeeze? Does it distort the image? |
| re: TV Aspect Ratios??? | Brad-
Jul 6, 2001 4:24 PM | | There is because of overscan. Philips, Zeniths, Magnavox, RCA, and GE
have more overscan. That means their pictures tubes don't display the entire picture that is transmitted. All televisions have overscan, but those above have more. Since overscan somewhat zooms in on the original picture, the picture shown on the tv will be slightly larger than better sets with less overscan. So essentially, since with overscan, its looks like a slightly zoomed picture, the sets above will have thinner letterboxed pictures.
Televisions with less overscan, in which more of the original transmitted picture is shown are JVC, Sony, Panasonic, and Toshiba. These televisions will show thicker black bars. |
| 3 different aspect ratios | Brad-
Jul 6, 2001 4:32 PM | | The two television tube formats are 4:3 = 1.33:1 and (widescreen)16:9 = 1.78:1
There are 3 widescreen formats that can be displayed on a 16:9 television.
16:9 = 1.78:1(no black bars on widescreen tv), 1.85:1(very slight black bars on widescreen tv), and 2.35:1(slight bars on widescreen tv). |
| Excellnt point on the Over-Scan issue. | Smokey
Jul 6, 2001 6:23 PM | | 4runner58 point an excellent point concerning the different size of black bars on same 4:3 tube playing the same movie on different television, and Brad- hit it right on the nose with over-scan capability of each Tv. Some TV do go over board with over-scan adjustments.
For example while I was adjusting my 32 inch Tv for over-scan problem, while on some programs the screen was showing full picture, but on some programs which had darker scene, the picture shrunk some what and black bars( limit of projected picture) begin to appear on right and left of picture. Also when I switched from satellite source to local channel, not only the picture shrunk from sides but also from top and bottoms. There is a delicate balance between showing full picture and over scaning or unde-scanning with different type of programming.
This delicate balance can be achieved only with tender loving care that manufactures don't have time to do.
I guess the Tv manufactures are playing it safe too to over-scan their TVs as to make sure all type of programming fill the screen. I am sure they don't want to send out technician just to fix a minor problem such as over-scan. But as Brad point out some Tvs have tendency to over do it. Not only these type of over-scan rub the consumer of precious optimum picture height and width, but also make the picture size change dramatically from bright scene to darker scene which is very evident with stationary images.
Anamorphic squeeze is the concentration of all of vertical resolution onto only shown picture between black bars. 16:9 enhanced mode focuses vertical scan lines in the 16:9 letterbox portion of the screen, improving the picture quality of letterbox-format movies and programs. |
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