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Discussion Starter #1 (Edited)
It turns out that in addition to broadcasting Last Day of the Dinosaurs in standard definition and high definition this Sunday, the Discovery channel and the Discovery World HD channel will also be broadcasting the show in two different versions of 3D: Anaglyphic 3D and Active 3D.

Anaglyphic 3D is the technical term used to describe the traditional method of generating a stereoscopic 3D image on a regular television using inexpensive glasses.

Active 3D, also known as Alternate-frame sequencing 3D is the term used to describe a recently developed method for presenting a stereoscopic 3D images. To view Active 3D images, you will need a new 3D ready television and expensive active shutter glasses.
 

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Do you have a source for this information?

Hugh - just to clarify, despite Discovery calling this "True3D" on their web-page, it's more than likely using the side-by-side (SbS) format for broadcast. This is a shared-frame configuration meaning the left and right eye images share a standard video frame. This allows for compatibility within existing 2D broadcast infrastructures and delivery paths but at the expense of horizontal resolution.

So it's debatable whether the 3D image can still be considered HD given the resolution numbers at this point.

I have yet to hear of a broadcaster/carrier - in Canada at least - broadcasting full-resolution, frame-alternating 3D video like Blu-Ray is capable of.
 

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The 3D version, supposedly, is going to be True3D (their "version" of side-by-side 3D) and it will be broadcast on Discovery World HD after the non-descript version (ie it can be in 2D or in anaglyph 3D).

The 3D image is still, legally, HD because 1080p designation is only describing the vertical resolution. It can be 1920x1080p (full-spec 16:9 HD), 1440x1080p (all older camcorders and some new ones use this resolution) or in the case of 3DHD (side by side) is 960x1080p. They are all still 1080p, they just hide the fact that it is not 1920 pixel across.

Unless the cable provider is willing to change the cable box to HDMI 1.4 capable, then frame-sequential 3D will never be available. Furthermore, frame-sequential 3D will require higher bandwidth. Something that cable providers want to spend less (so they can have more channels) rather than more (bandwidth).
 

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So it's debatable whether the 3D image can still be considered HD given the resolution numbers at this point.
FYI, never said it was HD.

As discussed in the past, I really don't consider side by side to be HD.
 

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Please if you wish to discuss the show see this thread or your post will be deleted.

This thread is about Anaglyphic 3D vs. Active 3D.

I put this thread up simply to help folks with the terminology since this show is actually showing both types and it could prove to be confusing.
 

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Also as an addition, there are variants of anaglyph 3D.

The most common for print media is red-blue anaglyph, there is also red-green, red-cyan, green-cyan. Maybe there is (are) more variants Hugh can add to this info.
 

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The 3D image is still, legally, HD because 1080p designation is only describing the vertical resolution. It can be 1920x1080p (full-spec 16:9 HD), 1440x1080p (all older camcorders and some new ones use this resolution) or in the case of 3DHD (side by side) is 960x1080p. They are all still 1080p, they just hide the fact that it is not 1920 pixel across.
None of the Canadian networks, channels or carriers broadcast 1080p. In fact, Bell-TV broadcasts in 720p. So in the case of side-by-side 3D, you are getting 1280 horizontal lines divided by 2, so 640x720 for each eye which is less horizontal resolution than DVD.

The other carriers broadcast HD in 1080i which only has 540 lines of vertical resolution. So the 1920 lines of horizontal resolution divided by 2 is 960x540 for each eye.

Technically then, anaglpyh should have more resolution given there is no frame sharing. But of course it suffers from poor colour reproduction, among other things.
 

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My only mistake is putting 1080p vs 1080i

You are correct, HD cable is 1080i max. The fact that Bell downconvert the 1080 channels to 7e0 is not the broadcaster's fault. Discovery World HD is 1080i natively.

Your calculation of 1920x540 is wrong. That is for top-bottom 3D. Side-by-side 3D is 960x1080i.

Also people pay too much attention on pixel count just like camera''s megapixel count. It's the overall performance that matters and side-by-side 3D is leaps and bounds better than anaglyph even if the anaglyph 3D is presented in Ultra Hi-Def resolution.
 

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Your calculation of 1920x540 is wrong. That is for top-bottom 3D. Side-by-side 3D is 960x1080i.
David, to clarify - I didn't post 1920x540, I posted 960x540 for side-by-side 3D.

The 960 number is exactly half of 1920 which is the horizontal resolution of a 1080i signal. This is split since two frames (left eye, right eye) are sharing it.

The 540 number comes from the fact the 1080i signal is of course interlaced. So at any given moment, there is only ever 540 lines of vertical resolution on the screen that alternate between odd/even.

Pixel count is important for large screen setups like 100"+ projectors.
 

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Which is still a form of anaglyphic.

Honestly guys, I think you are discussing a molehill and missing the mountain.

For the vast majority of us, it comes down to "Do I need the cheap glasses (anaglyphic) or an expensive 3DTV system (Active 3D) to watch the show"

For many readers/members, anaglyphic 3D and Active 3D are new terms that need to be added to our jargon.
 

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The 540 number comes from the fact the 1080i signal is of course interlaced. So at any given moment, there is only ever 540 lines of vertical resolution on the screen that alternate between odd/even.

Pixel count is important for large screen setups like 100"+ projectors.
Because this is so far off topic (as like what Hugh mention, this thread is only to talk about the difference between anaglyph and frame-sequential), this is my final post regarding the resolution.

Just because it's 1080i, it can't be calculated as 540. Just like nobody call 480i as 240 lines. Besides, your projector will de-interlace the 1080i to 1080p anyway. At least my projector on the 9ft screen does that and all FPD and projectors that I know of do that. You'll never see only 540 lines at a time.

Going back on topic, do you know exactly when they're showing the 2D version, 3D anaglyph and 3D side-by-side? On the IPG it only says "(title)" without any 2D/3D designation, followed by the same show but with "3D" behind it, followed by the exact same show right after (but again without any 2D/3D designation at all)
 

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Discussion Starter #13
See post #5 if you've had a post deleted
 

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HDMI 1.4 is not required for 3D - A good (real) 1.3 works perfectly......Unless you work at BB or FS and argue (which they did with me) that the Monster 1.4 is the only thing that works :^)

Thanks for the heads-up Hugh - I will try and check it out.
 

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I love that active shutter glasses are becoming popular now... I am colour blind to most reds, and have not be able to enjoy 3D my entire life... LOL

I work at a place that has a 3D theatre with active shutter technology, and I can tell you, live action 3D is amazing. It truly adds depth to the movies.
 

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but you still should be able to see true 3D presentation at various movie theatres since they are all using circular-polarized glasses and not anaglyph.
 

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Of course there are 3D passive TV displays as well that use the circular polarized glasses that cost $1.50. The expense is all in the display. So the glasses for your 3D Superbowl party of 20 cost $30 instead of $3000. Active and passive are the two standards that should be discussed. Anaglyph(red eye green eye) is obsolete, poor man's 3D really.
 

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I tried a 3d tv with shutter glasses at bestbuy running monsters v aliens and I was not terribly impressed. Do these tvs require critical set up to get the 3d effect correctly?
 

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yes.

1. brightness and backlighting calibration is needed
2. the darker the room (well, the way it supposed to be anyway) the better you'll see the 3D effect.
3. the only brand I've tested that shows active 3D with NO crosstalk whatsoever is the Panasonic. Every single brand outside of Panasonic have crosstalk problem which in my case gives me severa headaches.
 
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