Help needed on 3D source for 3D compatible projector

[tma]

@sam9s: Quite a detailed post!

Can you plz clarify:

"... that the 3D Bluray or any Bluray Movie content need 120Hz display. No it doesnt. ..."
I can understand that part for Non-3d content but for 3d content is it not requried to have 120Hz? There is no 48Hz (24x2) display mode for 3d or is it? Also the active 3d glasses have 120Hz 'refresh' rates.

".. the same content is been refreshed or displayed at 5 or 10 times a second 24x5=120Hz or 24x10=240Hz. Giving the image a false "smooth" appearance. ..."
If the SAME image is displayed multiple times how will that result in smoothing of the display? Unless some frame interpolation is done, there wont be any smoothing effect or is something else being done?

"... @ARN the converter you are buying is just to convert the conventional 2D content in to 3D, and might not provide you with enough depth ..."
The converter supports 120hz refresh rates so that 3d can be seen with the pj in question. Also, there is mention of 3d depth setting adjustment but dont know how good that is. Thus the convertor seems to be an option for PC-Ready / DLP pjs which need 120Hz. In these aspects is there any better alternative?

 

[kaushik]

arnprasad i will suggest few things

* aim for a simple 3d , more you dig more your life will endup in disappointment
* diy screen rocks , just only -ve is it is fixed like canvas takes just 1 day to build
* pc solution is more flexible but noisy, and bulky you will not prefer
but with SS PSU and basic graphics card you may be able to make a 3d converter PC
*media player is a must have all the time moving laptop is hassle

 

[arnprasad]

Well late to chip in, @Arn, few point I would like to share, hope thats makes some sense.


Best of luck with your purchase ....

Regards
Sammy

Well all I can say, apart from thanks, is that you are too smart for me. Just like your detailed main on HTPC/NAS - this one too is very detailed and frankly for my old brain - a bit hard to understand although thanks to my 3d research in the past 15 days - I do understand most parts of your post:lol:

Thanks again for your post and let me reread your post to fully understand it.

Also you mentioned TV many times in your post - my current predicament is the Acer 5360. Based on posts in avsforum I gather the Monoprice will help me play my ripped hsbs 3dmovies on my laptop and display using the PJ.

Today I spent 250 dollars for Monoprice convertor plus 4 dlp link glasses. I am hoping even if I decide to go with HTPC, I can sell these to someone on the forum for atleast my cost price. Guess even for HTPC I will still need the DLP glasses!

 

[sam9s]

@sam9s: Quite a detailed post!

Can you plz clarify:

".. the same content is been refreshed or displayed at 5 or 10 times a second 24x5=120Hz or 24x10=240Hz. Giving the image a false "smooth" appearance. ..."
If the SAME image is displayed multiple times how will that result in smoothing of the display? Unless some frame interpolation is done, there wont be any smoothing effect or is something else being done?

You yourself to an extent have answered your question, yes to comprehend the change, interpolation is done in LCDs (not plasmas, Plasma is a different story all together, I have less knowledge on that part). Interpolation technology takes the 24 video frames per second, and uses a mathematical algorithm to create entirely new video frames to be added in between the original frames, providing that smooth appearance.

Please keep in mind, the the original source refresh rate is independent of the display refresh rate. Source refresh rate for BD is and was always 24Hz.(23.976 to be precise)

If you have apprehensions about my explanation, you can venture out these threads, though the discussion is something different, it has enough references on refresh rates to authenticate what I am stating here

HTPC: 1080p/24 and refresh rate - Blu-ray Forum

http://www.avsforum.com/t/1175250/dvd-and-bluray-refresh-rate

Refresh rate - Wikipedia, the free encyclopedia

(Just scroll down to read content under two headings ....Televisions, specially the last paragrapher (Many high-end LCD televisions.......)
and Displaying movie content on a TV

If you will go in detail you will also learn concepts like pull down. which is also one aspect of what we are discussing here.

The converter supports 120hz refresh rates so that 3d can be seen with the pj in question. Also, there is mention of 3d depth setting adjustment but dont know how good that is. Thus the convertor seems to be an option for PC-Ready / DLP pjs which need 120Hz. In these aspects is there any better alternative?

All I said was "might", the level of depth and consistency hugely depends on the algo that the device is using. Even the best 2D to 3D conversion found on 3D LCDs does not come even close to what experience, actual FS 3D provides. My statement was just to reflect that ARN might be under the impression that a converted 2D to 3D video will look as good as the original. Hence a word of caution before he spends 200+ USD on this device.

Just my 2 cents ....

Regards
Sammy

 

[sam9s]

Here @tma I found an excellent article to explain what I have stated here ..... a must read ..

Video Frame Rate vs Screen Refresh Rate - What You Need To Know

Just reiterating and quoting a para from the same article, for the sake of people who would not read the entire thing..

If you have a TV with a 120hz refresh rate that is 1080p/24 compatible (1920 pixels across the screen vs 1080 pixels down the screen, with a 24 frame per second rate). The TV ends up displaying 24 separate frames every second, but repeats each frame according to the refresh rate of the TV. In the case of 120hz each frame would be displayed 5 times within each 24th of a second.

In other words, even with higher refresh rates, there are still only 24 separate frames displayed every second, but they may need to be displayed multiple times, depending on the refresh rate.

 

[tma]

The confusion I had after reading your original post was I guess due to two similar sounding but different concepts - FRAME rate and REFRESH rate..

A basic info on this would be Higher Frame Rates | Christie Digital

Also my question for refresh rate was specifically for 3D NOT being 120 hz..
I think for 3D, the higher the refresh rate the better even if the actual frame being shown is duplicated(flashed).

The repeat of the same image (flashing) makes sense for 2d thus 24fps will need to be repeated on higher refresh rate(120Hz) display. Anything less than 30fps for each eye will be too jittery for 3D though.

 

[sam9s]

Well all I can say, apart from thanks, is that you are too smart for me. Just like your detailed main on HTPC/NAS - this one too is very detailed and frankly for my old brain - a bit hard to understand although thanks to my 3d research in the past 15 days - I do understand most parts of your post:lol:

Thanks again for your post and let me reread your post to fully understand it.

Also you mentioned TV many times in your post - my current predicament is the Acer 5360. Based on posts in avsforum I gather the Monoprice will help me play my ripped hsbs 3dmovies on my laptop and display using the PJ.

Today I spent 250 dollars for Monoprice convertor plus 4 dlp link glasses. I am hoping even if I decide to go with HTPC, I can sell these to someone on the forum for atleast my cost price. Guess even for HTPC I will still need the DLP glasses!

Hope I was able to clear few concepts, tried to make it as layman term as possible ....
To play SBS you display should be able to render the signal, in your case your projector, if it has the option to play SBS 3d it will, irrespective of the source as SBS can be played via any media source. Dont be concerned about the refresh rate, most current gen LCD, and Projectors can display the BD at true 1080p/24hz, if not then pull down (another mathematical technique) will take care of it. But you would not get stuck.

Your mono price for me seems to be just a converter for 2D content conversion to 3D. If AVS guys have recommended monoprice to play SBS content on you projector, then I suppose your projector cannot render SBS signals (which s strange as SBS is just a 2D image split in to half and all the display does is to combine it to make it 3D via glasses). All 3D LCDs can do SBS.

Let me research on this ..... r u sure your projector cannot do SBS have you tried playing any SBS content and viewed it via the supplied glasses with the projector.

 

[sam9s]

Also my question for refresh rate was specifically for 3D NOT being 120 hz..
I think for 3D, the higher the refresh rate the better even if the actual frame being shown is duplicated(flashed).

Would not make any difference, even if your TV has that 120 refresh rate, it does nothing, the content (source is at 24Hz, yes even for 3D) so your BD player will always set the TV to 24Hz before it starts the movie (3D or Normal). This is ofcourse if your TV does support true 1080p/24Hz.(which all current gen LCDs does) Else in rare case (old TVs) pulldown will occur.

If you manually force and try to play a 24hz content with that 120Hz or 240Hz "Motion Plus" switched on, interpolation will occur and that would result your movie look like a Star Plus soap opera. Which ruins that "film" feel we have while watching a movie.

Try this experiment, most of the BD players display the source refresh rate on the top right corner of the TV when the player starts. put a movie any (3D or normal) and start the player (I can vouch for Panasonic DB-60) and you will see it displaying 1080p/24hz at the top corner of the TV before it starts to play the movie .....

The repeat of the same image (flashing) makes sense for 2d thus 24fps will need to be repeated on higher refresh rate(120Hz) display. Anything less than 30fps for each eye will be too jittery for 3D though.

No it wont, the source for 3D Bluray also is set to 24Hz, the difference is 24Hz is for each eye, effectively making it 48Hz, which is easily manageable for LCDs.

The only time we need true 120Hz display is when we are gaming in 3D, as that takes a lot of toll (different topic of discussion)

Regards
Sammy

 

[arnprasad]

Hope I was able to clear few concepts, tried to make it as layman term as possible ....
To play SBS you display should be able to render the signal, in your case your projector, if it has the option to play SBS 3d it will, irrespective of the source as SBS can be played via any media source. Dont be concerned about the refresh rate, most current gen LCD, and Projectors can display the BD at true 1080p/24hz, if not then pull down (another mathematical technique) will take care of it. But you would not get stuck.
.

Thanks. Although your explanation was laymanish - just that some laymen like me aren't very smart:lol:

From what I understood, this projector is 3D ready which means although it can display 3d signal, it does not do any processing itself. Also to display a HSBS 3D signal - it needs feeds in 120Hz which my current laptop adapter settings does not have (as it has an intel integrated graphics card). Hence I need some adapter that takes my 60HZ HSBS signal from laptop and converts it into 120HZ. That is all I wanted my Monoprice to do. I am not looking at converting 2D to 3D. My Panny TV also does that and I was never impressed.

Thanks again.

 

[sam9s]

Thanks. Although your explanation was laymanish - just that some laymen like me aren't very smart:lol:

From what I understood, this projector is 3D ready which means although it can display 3d signal, it does not do any processing itself. Also to display a HSBS 3D signal - it needs feeds in 120Hz which my current laptop adapter settings does not have (as it has an intel integrated graphics card). Hence I need some adapter that takes my 60HZ HSBS signal from laptop and converts it into 120HZ. That is all I wanted my Monoprice to do. I am not looking at converting 2D to 3D. My Panny TV also does that and I was never impressed.

Thanks again.

Not trying to be too teachie (Yes I invented that word ,, ) ..... please get out of that Hz confusion, you DO NOT need to feed a 120Hz signal to display 3D SBS. Any laptop, computer, media player can play an SBS file. There is no conversion from 60Hz to 120Hz for SBS.

Just one question ::: Have you tried playing an SBS file from your laptop connected to your projector (without the converter ..??)

EDIT :: Just researched on your projector, and it seems your projector is not a native 3D projector. but 3D ready (another marketing gimmick), meaning for proper frame sequential 3D, the projector need to be connected to a PC with NVIDIA 3D Vision kit (with a compatible GPU), which would also supply the glasses and the receiver. And you projector is capable of displaying the result.

Now for SBS I doubt that your projector has any native 3D mode that would convert the SBS to 3D, hence might be the need for those converters (Monoprice). (I would still say give it a try first, look for 3D modes supports somewhere in the menu)

On the positive side..... this projector provide 120Hz which can be benificial for 3D gaming, plus ofcourse the ability to display the 3D end result. But All processing has to be done by a separate source (PC with nVidia vision kit in this case)

Personally this projector aint a worth buy, coz for different 3D formats you need to have different ways for this projector to work ...... (A separate PC with nvidia visoin kit for FS 3Ds and monoprice converter for SBS 3D) ....Assuming that the projector does not have any native 3D mode for SBS.

Regards
Sammy

 

[arnprasad]

Not trying to be too teachie (Yes I invented that word ,, ) ..... please get out of that Hz confusion, you DO NOT need to feed a 120Hz signal to display 3D SBS. Any laptop, computer, media player can play an SBS file. There is no conversion from 60Hz to 120Hz for SBS.


Regards
Sammy

teacher techie = Teachie - thats smart for sure.

I have ordered the projector+25ft HDMI+4 DLP link glasses+Monoprice and currently with my colleagues in US. Expected to receive them around 17th Dec. Hence cannot try anything now.

@CGpraveen has this projector - maybe he can try playing at normal settings a ripped 3d file.

Not sure why you say this projector aint worth buying since at its price - most people have said its a good buy.

3d ready projector are around 250 dollars more.

I am hoping all said and done - if I am not satisfied or prefer to go a different route - I can still sell my stuff -say used for 1-2 months - at my cost price - hopefully no losses for me.

Again remember - although I am buying this because this the "in thing" in home entertainment - on a weekday I will not touch it and even on weekends, I might watch 2-3 movies a month. Hence I am not expecting heaven from this projector - just a nice big picture with a quality matching my 720p Plasma.

I dont play any games on my laptop. I only have a Wii which outputs at 480p. So I am hoping my kids will enjoy Mario Kart Wii and other games on a 10 feet wide screen.

I have watched these ripped 1 GB HSBS movies on my Plasma - although its good - I never felt stuff coming out of the TV screen threatening to hit my face. I have not seen a 3D movie in theater recently (only chota chetan decades back!!). Hence I am hoping that the occasional ripped 3D movie will have better effects than my Plasma.

Given these requirements - hopefully it will not be a bad choice.:yahoo:

 

[manoj.p]

Ah - The Hz discussion. Let me pinch in too.

Some facts to understand -
source - Film source was 24 frames per sec. Video source is 25 frames/sec for PAL, 29.976 for NTSC. Even though movies are now also shot in digital, the frame rate has stuck with 24 frames, exception being "The Hobbit" which is shot in 48 Hz.
Bluray is specified at 24 frames (23.976) and 30 frames. There are some video formats which have 60Hz too. So the formats are 1080px24, 1080px30, 720px60 and these are supported by HDMI. For 3D, one more format was added which is 1080px24/eye and its supported with HDMI 1.4.

Display - Normal LCD tv's and plasmas were 60 Hz initially. They were doing 2:3 pulldown. Meaning they were converting 24 frames to 30 first and then showing each frame twice. For every 2 frames of 24, they were making 3 frames out of it.
To avoid this 2:3 pulldown (because it made some frames appear skipping, especially in panning scenes), they come out 120 Hz. Now, there was no need to do any pulldown. Films were shown 5 frames repeated (24 x 5=120) and videos were shown 4 frames repeated (30x4=120). This is the best solution and does not make it look too processed and unreal. But display manufacturer's didn't stop at that. They came out with Creative Frame Interpolation, which was creating the data in between. That's what gives the movies the look of soap-opera type, unreal.

Now, back to our question of 3D. There is two types of 3D.
Frame sequential - This is 1080px24 per eye. Meaning, actualy its 1080px48 both eyes. It's transmitted to the display as such. Now, 3D can be shown at 24 Hz, 48 Hz, 60 Hz - there is no problem. But users will notice the flicker at these frame rates. Even more with the active glasses. So, the rate at which flicker disappers is 120 Hz. All the 3D displays take the 24 frames per eye, do 2:3 pulldown (convert to 30 Hz and then show twice). That makes it total 60 frames per eye, 120 frames total.

During all this, the player is only outputting 1080px24 per eye. You would need HDMI 1.4 cable.

SBS/TopNBottom - This is half resolution 3D. Essentially, its 1080px24 source and transmitted as such. It will have a single frame containing both left and right picture, squeezed next to each other. it will have 960x1080 left, 960x1080 right making it total 1920x1080. The source and cable does not treat it any different than a normal 1080p signla. However, the display sees it as 3D source. Then it will brake the 1920x1080p picture, into two 960x1080 pictures, upscale each to 1920x1080. From here on, it will do 2:3 pulldown and convert 24 frames to 30 and show each twice. that's 60 frames per eye, 120 frames for two eyes.

For PC based solutions, there are two alternatives:
Use HDMI 1.4 compliant 3d card - This will output 1080p24 per eye, like any bluray player. No difference there.

The same card can do the 2:3 pulldown itself and up the refresh rate to 120 Hz. So, it will take the source, convert to 30 Hz, then double to 60 hz per eye. But the limitation here is HDMI bandwidth. HDMI can't do 1080px120. Max it can do is 1080px60 or 720px120. So if you want to output 3D signal through HDMI, it has to 720px120 Hz. The Display can upscale it to 1080p. Now, if the display does not have 3d emitter, then nvidia does provide one.

There are some dual link display cards and ports, which support 1080px120, but those are only on computer monitors. Tv's/projectors do not have that, so it's the mute for AV crowd.

 

[gcpraveen]

I normally connect projector on weekend nights! I can try playing 3d ripped sbs via xtreamer and update!
@arnprasad : today evening, you can come to my place and try out the possibilities.

Thanks,
Praveen.
sent from SGS2 skyrocket.

 

[sam9s]

teacher techie = Teachie - thats smart for sure.

I have ordered the projector+25ft HDMI+4 DLP link glasses+Monoprice and currently with my colleagues in US. Expected to receive them around 17th Dec. Hence cannot try anything now.

@CGpraveen has this projector - maybe he can try playing at normal settings a ripped 3d file.

Not sure why you say this projector aint worth buying since at its price - most people have said its a good buy.

3d ready projector are around 250 dollars more.

I am hoping all said and done - if I am not satisfied or prefer to go a different route - I can still sell my stuff -say used for 1-2 months - at my cost price - hopefully no losses for me.

Again remember - although I am buying this because this the "in thing" in home entertainment - on a weekday I will not touch it and even on weekends, I might watch 2-3 movies a month. Hence I am not expecting heaven from this projector - just a nice big picture with a quality matching my 720p Plasma.

I dont play any games on my laptop. I only have a Wii which outputs at 480p. So I am hoping my kids will enjoy Mario Kart Wii and other games on a 10 feet wide screen.

I have watched these ripped 1 GB HSBS movies on my Plasma - although its good - I never felt stuff coming out of the TV screen threatening to hit my face. I have not seen a 3D movie in theater recently (only chota chetan decades back!!). Hence I am hoping that the occasional ripped 3D movie will have better effects than my Plasma.

Given these requirements - hopefully it will not be a bad choice.:yahoo:

Ok, not worth buying might sound a bit harsh, apologies, but getting two separate units for 3D sounded a bit far fetched for me. I am not updated with projector prices and at what minimum price one can get a proper 3D projector, but if this combination is cheaper than the cheapest proper 3D projector then I suppose it makes some sense, given the fact that your usage is so limited.

Regards
Sammy

 

[sam9s]

. All the 3D displays take the 24 frames per eye, do 2:3 pulldown (convert to 30 Hz and then show twice). That makes it total 60 frames per eye, 120 frames total.

During all this, the player is only outputting 1080px24 per eye. You would need HDMI 1.4 cable.

Just a small addition, this pull down will only happen if the 3D LCD is non 1080/24p compatible, if the LCD can display 1080p 24Hz (which most current gen LCDs can) then there is no need for pull down as then the 120Hz refresh rate of an LCD will just show the same frame 5 times to compensate .....

 

[manoj.p]

Just a small addition, this pull down will only happen if the 3D LCD is non 1080/24p compatible, if the LCD can display 1080p 24Hz (which most current gen LCDs can) then there is no need for pull down as then the 120Hz refresh rate of an LCD will just show the same frame 5 times to compensate .....

All the 1080p displays are 24p compatible. Cause, they need to be able to lock in to Bluray source which is 1080p24.

But the 3D display can show 120 Hz for both eyes, meaning it will show 60 Hz for left eye and 60 Hz for right eye. There is no way for the display to take 24 frames and show that at 60 Hz without doing 2:3 pulldown. There are few projector which avoids it. One is the JVC RS40/50/60 projectors which show the 3D at 96 Hz (48 hz each eye). The another one I had seen was the Digital Projection Titan. That was doing at 144 Hz (72 Hz per eye)

If its just the 2d signal, then yes, it can show the just take the 24 frames and show it 5 times. Although many tv manufacturers don't do that and instead do CFI. Talk about taking something nice and totally mess it up.

 

[sam9s]

^^ mmm for TVs that are locked at 120Hz, for 3D, pull down makes sense, as 24x2=48hz does not fit in any multiple of 120 ......good info, thanks for sharing, always a good learning experience ........

 

[manoj.p]

^^ mmm for TVs that are locked at 120Hz, for 3D, pull down makes sense, as 24x2=48hz does not fit in any multiple of 120 ......good info, thanks for sharing, always a good learning experience ........

No problem at all. That's the purpose of the forum, share and learn.

 

[kaushik]

prasad, i also have joined the 3d ready brigade with a Acer 5350 .
i will do 3d stuff slowly .

first target is the hardware 2dto3d device and a set of glasses from china in 24USD

 

[Santy]

Here we go... getting ready for 3D

I connected my Optoma HD66 projector to the PC which enabled the 120Hz option on the graphic card setting. I was glad when it showed up on the Catalyst.

I connected it through the AVR using the existing 30 feet cable, which is basically, cheap. So once switched to 720p 120Hz, the picture got distorted, with lot of colored bands and grains. I did not study it further, immediately disconnected fearing damage to the PJ or GPU.

But what I sense is that the HDMI cable is not having adequate bandwidth to carry 120Hz signal. What is your take on this guys?

Today I am planning to move the PC closer to PJ and try it out with a shorter cable. If it works, then all I would need is a pair of DLP active shutter glasses and a good quality, monoprice or BJ kinda HDMI cable? Am I going wrong anywhere?