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1080P receiver coming soon ?

Discussion in 'DISH™ High Definition Discussion' started by ken310, Mar 7, 2006.

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  1. ken310

    ken310 Legend

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    Feb 24, 2006
    I seem to see a relationship between fps and 60 Hz being the power cycle in the US but when 24 and 30 are used I lose it. 30 maybe but 24 fps?

    "since frames keep a fixed phase relationship to the 60 Hz power-line cycles"
    and one hertz is defined as one cycle per second.

    In my thinking the rpm of the 'machine' running the film would be what changes fps but obviously it's not that simple.

    When speaking resolution is that per screen or a measured area like a inch or ?
     
  2. harsh

    harsh Beware the Attack Basset

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    24fps is the standard for celluloid film and they had to figure out how to make it look good at a different frame rate without making the movie run fast.
    Do a web search about 3:2 pulldown. It involves "combining" parts of successive frames. Make sure you understand the difference between fields and frames.
    Television resolution is an analog term. It doesn't have anything to do with pixels or matrices. "480 lines of horizontal resolution" is related to how many complete transitions from dark to light could be seen on a single (horizontal) scan line. Analog technology cannot turn on a dime but as the resolution increases it can make more full transitions in a single pass across the screen.

    On the other side of the fence we have digital technology which is incapable of doing grays. Digital must simulate grays by flickering.

    Don't even get started about combining flickering with wobbulation; the current technology behind consumer class 1080p DLP.
     
  3. Rogueone

    Rogueone Hall Of Fame

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    i like that last line harsh :)

    Ken, the relationship between ac 60hz and tv 30 is simple. TV is interlaced, so each 1hz it draws a field. Each 2 fields completes a frame. So 30 frames are drawn per second. When you start talking 720p or 1080p, the signal would ideally be 60 hz or frames. If the 720/1080p is reproducing 1080i or 480i, then it has to draw each full frame twice. thankfully the brain can not detect this, it all happens too quickly.

    as to movies and 24 frames, back in the day, it was likely done because of cost. 24 frames per second of film saves a lot of money over 30 frames, and since it is film on a continuous reel passing by a light which is projecting the image onto a large screen, there was no need for the system to be defined by AC. And I say 'defined by" for a reason. PAL is a 50 hz system, or 25 frames of interlaced video. so their TV's are based on their electrical system being only 50 hz. I suppose film is just transmitted normally over there, with maybe 1 frame repeating or such. but here, they transmit a 5th frame for every 4 real frames of film. not sure how they build the 5th frame, but I guess that is why it's called "edited for tv" :) (besides the cropping down to 4:3 and cutting out the occassional scene or language).
     
  4. Oompah

    Oompah Cool Member

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    "Edited for TV", I think, has more to do with content, 4:3 formatting, and/or fitting into a time slot (sometimes leaving time for commercials).

    Getting 5 frames from 4 uses a technique called "3:2 pulldown".

    3:2 pulldown takes advantage of the fact that interlaced video is made up of fields that change 60 times a second. Call each frame on film a 'cel' to avoid confusing film frames with video frames. Since 60 fields represent almost* exactly the same time as 24 cels (1 second) means that 10 fields (5 frames) represent the same time as 4 cels, and 5 fields represent the same time as 2 cels (60/24 = 10/4 = 5/2). Telecine (TM) machines do the conversion by projecting sequential film cels onto a video imager for times that alternate between 3 fields and 2 fields. That is:

    Cel A -> Field 1 (Frame 1 odd lines)
    Cel A -> Field 2 (Frame 1 even lines)
    Cel A -> Field 3 (Frame 2 odd lines)
    Cel B -> Field 4 (Frame 2 even lines)
    Cel B -> Field 5 (Frame 3 odd lines) [5 fields, 2 Cels]
    Cel C -> Field 6 (Frame 3 even lines)
    Cel C -> Field 7 (Frame 4 odd lines)
    Cel C -> Field 8 (Frame 4 even lines)
    Cel D -> Field 9 (Frame 5 odd lines)
    Cel D -> Field 10 (Frame 5 even lines) [5 more fields, 2 more Cels]

    Cels A and C are shown longer than Cels B and D. Note also that Frame 2 is part Cel A and part Cel B, and and Frame 3 is part B and part C. When shown on an old-fashoned CRT those "mixed frames" (2 & 3) are of little consequence since each field is entirely independent of the one before and after; in fact, as far as NTSC is concerned, I don't think there is really any definition of whether a frame "starts" with an even or an odd field - they just get drawn sequentially with a subtle timing difference determining whether a field is odd or even, and any pair of fields could be considered a frame (except for scene changes, I suppose). Frame grabbers and digital equipment do care which is which, but the old analog equipment didn't.

    Here's a good explanation of the process, some artifacts generated, and what can be done to improve playback on modern equipment: http://www.dvdfile.com/news/special_report/production_a_z/3_2_pulldown.htm.

    * With NTSC, the frame rate is really 29.97 fps, not 30, but that 0.1% difference just gets lost in the noise.

    24p transfer and playback would make all this go away . :)
     
  5. Rogueone

    Rogueone Hall Of Fame

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    so wouldn't that still be "edited for TV" ? :) it's no longer in the original format, even if it is left in Letterbox :) hehe all of those changes make a tv movie "edited" from the theatrical version yes?
     
  6. James Long

    James Long Ready for Uplink! Staff Member Super Moderator DBSTalk Club

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    If we followed that standard everything we see would be 'edited for satellite'. :D

    What that label generally applies to is content. Removing a portion of each side of the screen is altering content. Removing scenes too racy or shocking for your network is altering content. Replacing words with silence, tones or dubbed alternatives is altering content.

    Spreading four cells of image to fit five frames of a television image isn't altering the content of the picture.

    BTW: Frame 2 and 3 in the example above are the ones I keep getting when I pause a movie. If you catch this during a fast action scene on frame advance the picture looks a little jittery.
     
  7. voripteth

    voripteth Legend

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    Monitors are said to be "flicker free" when they have a refresh of over 70 frames a second. Personally I have find movies often distracting at 24 frames a second because the flicker is so obvious. Then again I'm one of those weird people who can see the refresh on DLP sets. (Rainbows)

    If they can ever get the data to refresh at 70+ frames a second then I'd be happy! :D
     
  8. ken310

    ken310 Legend

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    Feb 24, 2006
    [/QUOTE] Frames keep a fixed phase relationship to the 60 Hz power-line cycles (in the USA). [/QUOTE]

    If speed is somehow 'regulated' by the 60 Hz in the 110vac we use it seems I/we have go back to our electrical current to understand ! ??
    A frame is broadcast by every 'pulse', a pulse being 1 Hz or cycle ?

    Analog (physical film) would be controlled by the rpm of the projector. The 24 fps started as analog right? still used by digital today? If so how do we regulate digital 24 fps using 60 Hz power? I'm still missing the relationship of 60 Hz to 24fps defined by 60 Hz power?

    My hdtv is 16:9, 1080i, 720p, 480p, 480i.
    What it displays is dependent on what's broadcast, hd being 1080i or 720p and it would seem 2 other factors. One being the receiver, the other being the tv itself ?
    HD signal is up-linked and down-linked via sat, compressed right?
    Then decompressed by the receiver at a max of 1080i or 720p ?

    Then we have this "upconversion".
    An example of upconversion would be 1080i to 720p, the later being better right?
    To "up-convert" to me sounds like using 5mb (random) data to make 7mb? The very word sounds like a oxymoron. Now to convert something to a different format which 'can' cost data, or downvert I understand but to add data from where ? sounds hummm well, wrong ?
     
  9. ken310

    ken310 Legend

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    Feb 24, 2006
    I read the page+ on 3:2 pulldown and have decided this and other data is giving me a head ache. :grin:
    http://www.dvdfile.com/news/special_...2_pulldown.htm.

    Hdtv or just sd is way more complicated then I have time to learn but I do believe I've got some of the basics. Complicated enough that I'll have to bow to the experts summations. Kudos to the brains that make this tech available to the end user!

    I'm beginning to think if I understand it it's probably not quite right :nono2:
    as there's a lot of variables in all this tech.

    Thanks!
    Ken
     
  10. Rogueone

    Rogueone Hall Of Fame

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    np Ken :)

    Just don't want you going to the local Best Buy and believing basically anything they say :) Keep in mind the age and experience of the person selling you a TV, and the fact they are an hourly person. There isn't any incentive to learn when you are hourly. Commissions places have the headache of the salesman pushing you toward a product, but they are also much more likely to have read up on and understood a technology enough to explain it :)

    I think the main point in buying HD right now is, buy what you can afford and the size that works for you. Both 720 and 1080 will look great compared to anything you've experienced in TV before, so does it really matter? decide if you want flat panel or slim projector etc., and what seems to work in your room. Preferrably don't buy the "cheapest" product, but don't overpay for a top of the line if you don't need it :)

    down the road a few years all this talk of 1080p will matter as there will actually be sets everyone can afford. At that point, 720p will be the entry level product line and 1080p will be the higher end set, even though there won't be 1080p sources unless the game consoles go that route. It's gonna take time to roll this out to all of America, gotta remember how big this place is and how many people still use rabbit ears :)
     
  11. Fifty Caliber

    Fifty Caliber Banned User

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    PAL-M which is used in Brazil is a 60 Hz system. Also there is a VCR standard known as PAL-60 which is also 60Hz. PAL-60 is not used for broadcast, and was invented for use by people (read US military) who travel to different nations some of which use PAL and others that use NTSC.
     
  12. ApK

    ApK Icon

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    It's an historical relic. ORIGINALLY TV refresh were linked to power line frequency, then they were standardized and the numbers stayed though though technology advanced.
     
  13. ken310

    ken310 Legend

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    The day I went in Best Buy the kid in there was clueless. They have a good selection and good prices but I don't expect much help. I bought a 32 or 34" Toshiba 16:9 hdtv. After viewing it at home I was thinking where's the Ahhhhh ? Like I felt with my first hdtv, a 53" Panasonic 16:9 big screen even in sd. I returned it only to hear " since you paid cash for it we'll have to send you a check in the mail", not allowed to have that much cash on hand. Thankfull I could return it. I went across the street to Circuit City and fell in love with a 34" Sony KD-34XBR960 although the price was higher it did/does give me the Ahhhhh felling. I love it and my new audio system. As usual the Sat receiver is my weakest link.
    Where did I spend the most time researching hdtv? The receiver. Where did I get screwed, the same.

    [/QUOTE]
    I think the main point in buying HD right now is, buy what you can afford and the size that works for you. Both 720 and 1080 will look great compared to anything you've experienced in TV before, so does it really matter? decide if you want flat panel or slim projector etc., and what seems to work in your room. Preferrably don't buy the "cheapest" product, but don't overpay for a top of the line if you don't need it :)
    [/QUOTE]

    To me a new hdtv is a pretty big investment. I'm the kind that wants the best but give me one with a scratched cabinet or ? so I can buy the best for less. I'd expect this tv to last for the next 4+ years or so. Then I'll give it to on of my children as I did my old (2 yrs) hdtv.
     
  14. Rogueone

    Rogueone Hall Of Fame

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    haha, TV's are suppose to last 10 years minimum :) Doh!

    why was the Tv you bought more at CC? just because you picked a more expensive model? CC price matches so if BB has the same set cheaper, CC would match that. I'm guessing you meant you just bought a more expensive unit.
     
  15. ken310

    ken310 Legend

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    Wouldn't that be nice ?
    If you want to stay on the cutting edge of tech it will cost you! It has cost you/us depending on how long you've had satelitte, Myself, 17+ yrs. E* now Dish. I wanted HDMI to go with my new 942 receiver (the one I haven't received yet) and 720p. This 2nd hdtv is actually a completly different type of hdtv as my first was a big screen and this one is only 34" but the HD quality is amazing.

    [/QUOTE]why was the Tv you bought more at CC? just because you picked a more expensive model? CC price matches so if BB has the same set cheaper, CC would match that. I'm guessing you meant you just bought a more expensive unit.[/QUOTE]

    BB didn't carry the high end Sony I bought.
     
  16. James Long

    James Long Ready for Uplink! Staff Member Super Moderator DBSTalk Club

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    I still have a TV I bought in 1984 ... I use it occasionally for dish and antenna pointing (it is a 13" set that fits nicely in a window).

    I just decommissioned a 19" set bought in 1987. It was still in regular use until my TVs were shuffled after getting my HD set last year.

    I don't expect TVs to last 10 years ... but I'm happy when they last 20.
     
  17. Rogueone

    Rogueone Hall Of Fame

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    haha, I expect nothing less than 10 years minimum operation, or the unit was crappy :) That doesn't mean I expect to still be watching it myself though haha

    I have a 13" from 1987 i bought on Superbowl Sunday so I could take it to work (Pizza Delivery) and set it up to watch the Redskins/Broncos game while I was picking up the next run :) it's starting to flake out, and I haven't used it regularly for 2 years, but it's there and sort of working after 19 years :D Then I have a 27" JVC from 1991 that was replaced with my 65" rpHD, and became my kids dvd/vhs unit. Now it's hanging on their bedroom wall (boy I hope those bolts hold). And a 20"er that's probably 5 years old.

    Since the 13" is dieing, and with the 622 coming soon, I've toyed with the idea of a little 15" 4:3 lcd unit at Sam's that accepts HD inputs HDMI and RGB, as well as PC, and has a 1024x768 glass so it looks better than the other 15" units with their 480p glass. It would make a very nice bedroom unit for under $300. Now, being LCD, I don't know, not sure I'd expect 10 years from an LCD TV :( hmmm .....
     
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