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Wake Up Call - Some People Are Kidding Themselves

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The original poster is actually talking about 1080p LCD projectors not LCOS, or SXRD or whatever.

While 720p is no match for 1080p, from a reasonable distance away the difference is barely noticeable and it should be said that 720p actually contains an impressive amount of detail, and a projector that has better contrast or is capable of throwing a more beautiful picture would be better.

But with that said there is no way my next projector will be a 720p DLP. It will be a 1080p for sure, and probably LCD if that is the best value for money.

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There is more to PQ than just resolution. I will gladly take a fantastic 720p which does everything right than a 1080p with flaws

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There is more to PQ than just resolution. I will gladly take a fantastic 720p which does everything right than a 1080p with flaws

Here speaketh the voice of reason.

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There is more to PQ than just resolution. I will gladly take a fantastic 720p which does everything right than a 1080p with flaws

I think I more or less said that in a round about way :)

but you also can not discount what information is being conveyed in those pixels

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There is more to PQ than just resolution. I will gladly take a fantastic 720p which does everything right than a 1080p with flaws

absolutely true, but the generic statement of the OP was what people felt was wrong.

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I think it comes aout at about 44% more pixels, but you also can not discount what information is being conveyed in those pixels.

720P (1280x720) frame has about 0.97 million pixels. 1080P (1920x1080) frame has about 2.07 million pixels. The gain is more than 100%. Am I missing something.

It is true that 720P could produce an impressive and detailed picture but it is also true that 1080P can produce a picture with 100% higher clarity and detail. However, it is questionable whether this additional detail would be useful to the viewer. This depends on the screen size, the seating distance and the information contained in the original material. There should be some cut of point in screen size that the difference between 720P and 1080P is not perceptible to human eye.

If the screen size is large enough (say few meters), and the original material contains independently perceptible 2.07 million pixels (say blu-ray), then one would easily see the difference between 720P and 1080P. The difference is huge and 1080P PQ is incredible.

If true-1080P material is down converted to 720P, then there is a good possibility that scaling errors would occur and the PQ could further degrade. Other way around, if SD material is upscaled, 720P may produce a better picture than 1080P depending on the scaler quality and design.

There are many more factors that need to be considered when choosing a projector - the resolution is only one of these factors but IMHO it is a very important factor especially if extra-large screens are used.

Best regards.

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I was always of the opinion that a size of 110" is the minimum size to justify an pj with displays approaching 80" in the near future that will become more apparent just watched Blu-Ray version of PlantEarth on a 130" screen with friends on a 720p pj and the shear size had then enthralled not the resolution so what I'm saying content also helps the size factor

cheers laurie

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720P (1280x720) frame has about 0.97 million pixels. 1080P (1920x1080) frame has about 2.07 million pixels. The gain is more than 100%. Am I missing something.

You are missing something. You can't calculate resolution and equate it to detail that way. If you have twice as many pixels in one dimension and twice in the other direction the picture will contain 4 times as many pixels but in no way would you perceive the image as being 4 times as detailed. It would be more acurate to say that the picture is twice the resolution.

The human eye is far more sensitive to vertical resolution than hoizontal resolution (part of the reason anamorphic DVD's work).

Hence a 720P projector has approximately 67% of the detail of the 1080P projector.

How evident this is is open to conjecture but I ran a thread on here a while back about a group of Greek AV enthusiasts that ran two seperate tests involving a 720P and a 1080P projector from the same family. They tested a Benq 8720 against a W10000 and also a Marantz 12S4 against an 11S1.

No one at either meet could tell the difference between the two at a viewing distance greater than 1.3 times the width.

Make of that what you will.

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You are missing something. You can't calculate resolution and equate it to detail that way. If you have twice as many pixels in one dimension and twice in the other direction the picture will contain 4 times as many pixels but in no way would you perceive the image as being 4 times as detailed. It would be more acurate to say that the picture is twice the resolution.

The human eye is far more sensitive to vertical resolution than hoizontal resolution (part of the reason anamorphic DVD's work).

Hence a 720P projector has approximately 67% of the detail of the 1080P projector.

How evident this is is open to conjecture but I ran a thread on here a while back about a group of Greek AV enthusiasts that ran two seperate tests involving a 720P and a 1080P projector from the same family. They tested a Benq 8720 against a W10000 and also a Marantz 12S4 against an 11S1.

No one at either meet could tell the difference between the two at a viewing distance greater than 1.3 times the width.

Make of that what you will.

Would have been good to see that shootout.

At 4-5 metres, a 720P projector limits your screen size to anything from 70 to 96 inch (ish)

But with a 1080P projector (providing the lumens are ample) you can go with anything from 90 to 130 (ish)

Yes, I agree, at some distances the difference won't be that noticeable but the idea of a bigger screen is appealing and this is

what people want (we are doing an average size of 115-125 inch now 1080P is starting to take off, whereas the average size 6-9 months ago was 82-96 inch.)

The other thing I noted was blu ray scaled down on a Z5 looked quite ordinary, that was at 4 to 5 metres on a 96 incher.

I noticed stair stepping on curves, screen door etc at around 3.5 metres but with 1080P one could sit that close with no issues..

Maybe I'm just too used to 1080P. I know I'd never go back to a lower resolution.

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I think the reason blu ray looked ordinary on your Z5 may be more to do with scaling limitations and video processing artifacts than the actual res of the PJ Rich... But i haven't done the comparison myself so can't really comment :D

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Would have been good to see that shootout.

At 4-5 metres, a 720P projector limits your screen size to anything from 70 to 96 inch (ish)

But with a 1080P projector (providing the lumens are ample) you can go with anything from 90 to 130 (ish)

Yes, I agree, at some distances the difference won't be that noticeable but the idea of a bigger screen is appealing and this is

what people want (we are doing an average size of 115-125 inch now 1080P is starting to take off, whereas the average size 6-9 months ago was 82-96 inch.)

The other thing I noted was blu ray scaled down on a Z5 looked quite ordinary, that was at 4 to 5 metres on a 96 incher.

I noticed stair stepping on curves, screen door etc at around 3.5 metres but with 1080P one could sit that close with no issues..

Maybe I'm just too used to 1080P. I know I'd never go back to a lower resolution.

Richard, I have no doubt that you're new crop of 1080P projectors absolutely put the Z5 to shame. Personally I find all D5 LCD projectors extremely flat and not engaging at all. The new 1080P projectors have so many other improvements that it's hard to determine which factor is giving you the biggest improvment. That's why I found the Athens shootout so interesting as both projectors were DC3 DLP's running on the same chassis using the same lens. Have a read:

Athens 1080P vs 720P Shootout

Here's what I had to say about it at the time:

"Interesting read Muzzer and it does raise some interesting points.

Note that they don’t say that there was no difference between the two projectors, just that the difference was subtle and hard to detect.

I found it interesting reading about the fact that somebody has looked at the encoding of HD material and worked out that in reality, most HD material is only “resolving” the equivalent of about 800 lines of vertical information (and I’m not talking about 2.35:1 material here) due to sampling, compression and the limitations of the cameras themselves.

It also appears that the scientific method of calculating the resolving capacity of the human eye that I used may be flawed in that it is based on static images rather than images in motion.

Please note though that one of the contributors to that thread started his own comparing the 720P TW700 with the 1080P TW1000. Once again he stated that the differences were subtle. But guess what? When he had to decide which one to keep, he kept the 1080P model and sold off the 720P. He found that after viewing the 1080P model for a while, it was hard to go back to the 720P model. Make of that what you will.

Gino also states that on his setup, he can see scan lines when running 720P which are invisible when he runs 1600x1200.

The digital equivalent of scan lines is screen door effect. A lot of guys in that thread state that they can see SDE at 1.5 times the screen width. They want to sit at 1.3 times the screen width so for them they feel the upgrade is worthwhile.

I can say that I see a big difference when running my PJ at 720P as opposed to 576P but I can’t see a difference between 720P and 1080i (my PJ won’t do 1080P) but this probably has more to do with the fact that my poor little 7”ES unit is running out of bandwidth and raster at the higher resolution and the fact that I haven’t had a chance to test it with HD sources.

What this really does bring home though is that if there is only a marginal difference in visible quality between 720P and 1080P, then there really isn’t going to be a difference at all between 2.35 material shown on a 720P Anamorphic setup and a conventional 1080P one. After all, a 720P in this mode is the equivalent of 960P anyway.

I think you’ll find in my original post that I stated that my personal opinion was that for those with an existing top notch PJ like the 8720, I would think that investing in a CIH setup would be more beneficial than forking out for a new 1080P model.

For those that don’t have a PJ yet or are replacing an older unit, they may get more of a benefit by going to one of the newer 1080P models. Why? Because it’s not just the resolution that has improved. In the LCD models the D6 panels are reported to have a native contrast ratio around 3 times that of the previous D5 720 panels. They are also inorganic which supposedly makes them immune to degradation. And look at the native CR of the new JVC. 15,000:1. Resolution isn’t everything and the new 1080P projectors have a few more tricks up their sleeve than just more pixels. The one exception to this may be if your looking to run a really big screen. Then it may be worth looking at one of the brighter 720P units (even a 3 chip DLP) and doing CIH with it.

Anyway, thanks for the thread. It was a great read. It actually makes me feel a lot better about running my existing PJ at 720P with BRD/HD-DVD for a while when I get home in that I probably won’t be missing out on much. Then again, did you see how many of those guys at the Greek meet were wearing glasses? 1/60th degree visual acuity? I think not!"

I still stand by most of that today.

Here's the DTV Thread where we discussed all this:

1080 vs 720

Reading that discussion makes me long for the good old days. Why can't we have a rational discussion like that these days? Must be the Hillbilly factor 'eh Foggy?

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And more of The Preacher's fine work from the linked thread above.

An “average” person has a visual acuity of approximately 1/60th degree in the vertical plane. That is, they can resolve individual lines if the angle between the adjacent lines is greater than 1/60th degree. As we get closer to the screen, the angle increases and hence we can resolve more, smaller lines.

So if we apply some basic trigonometry to the problem we can determine the distance away from a screen at which we can sit and fully resolve the number of lines. Then assuming a screen aspect ratio we can convert that factor and express it as the more common factor of screen width versus distance.

So what do we get assuming a 16:9 screen?

480P = 4.03 x Screen Width

576P = 3.36 x Screen Width

720P = 2.69 x Screen Width

1080P = 1.79 x Screen Width

What this means is that if you are sitting any further back than 4.03 x the screen width, you don’t need anything more than 480P. The average person will not be able to resolve any more detail. As for 720P versus 1080P, if you’re sitting closer than 2.69 x the screen width, you will see an increase in detail when you go from a 720P display to a 1080P capable one (providing you are using a true 1080P source).

The balance changes somewhat, however once you introduce 2.35:1 material and add an anamorphic lens to the 720P projector:

720P Anamorphic Squeeze = 2.02 x Screen width.

Therefore a 1080P display will allow you to sit approximately 10% closer than a 720P fitted with an anmorphic lens when displaying 1080P content. Not a huge margin.

Interestingly, if you sit any closer than 1.79 x the screen width, there is still room for improvement over 1080P. 2160P anyone? :D

You can see a graph I made up to illustrate these results in the following attachment.

Visual Acuity

For the flatscreen crowd, interestingly it shows that you would have to be sitting closer than 3m to a 50 inch display before you would get any improvement out of a 1080P display compared with a 720P one.

As for whether it's "worth it", that's going to be a personal decision. If owned a 720P projector already, I'd probably look at doing a CIH setup 1st before I spent the dollars on a 1080P projector. If I didn't have a PJ already, I'd probably try and stretch to a 1080P model. Each to their own.

Just notice the graph you created (linked above - under "Visual Acuity" & below) and Carton Bale's one are very similar which confirms that the information is both pertinent and accurate. Not quite sure about the validity of the anamorphic part as the pixels quantity are the same on the horizontal plane, though it is increased on the vertical plane. Must think about that one.

Preacher's Graph

Carton Bale's Graph

Edited by Highjinx

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Thanks for the info Preach, appreciate it!

I have to be quick here, but if one was to use a 720P projector, apart from say these entry level machines like Z5, AX200, TW700, HD70 etc.. and be happy with it's performance against say a TW2000 or a HC6000, how much would one be spending and would it be worthwhile if the price turns out to be say $1,000 less?... or can I expect to pickup a 720P projector for half the price of a 1080P machine and be happy with it's performance, enough to not warrant purchasing a 1080P machine? We would have to go DLP correct? If not what LCD 720P projector would one purchase to rival a 1080P LCD? They seem to be ripping the good gear out of these 720P machines these days...

Richard, I have no doubt that you're new crop of 1080P projectors absolutely put the Z5 to shame. Personally I find all D5 LCD projectors extremely flat and not engaging at all. The new 1080P projectors have so many other improvements that it's hard to determine which factor is giving you the biggest improvment. That's why I found the Athens shootout so interesting as both projectors were DC3 DLP's running on the same chassis using the same lens. Have a read:

Athens 1080P vs 720P Shootout

Here's what I had to say about it at the time:

"Interesting read Muzzer and it does raise some interesting points.

Note that they don’t say that there was no difference between the two projectors, just that the difference was subtle and hard to detect.

I found it interesting reading about the fact that somebody has looked at the encoding of HD material and worked out that in reality, most HD material is only “resolving” the equivalent of about 800 lines of vertical information (and I’m not talking about 2.35:1 material here) due to sampling, compression and the limitations of the cameras themselves.

It also appears that the scientific method of calculating the resolving capacity of the human eye that I used may be flawed in that it is based on static images rather than images in motion.

Please note though that one of the contributors to that thread started his own comparing the 720P TW700 with the 1080P TW1000. Once again he stated that the differences were subtle. But guess what? When he had to decide which one to keep, he kept the 1080P model and sold off the 720P. He found that after viewing the 1080P model for a while, it was hard to go back to the 720P model. Make of that what you will.

Gino also states that on his setup, he can see scan lines when running 720P which are invisible when he runs 1600x1200.

The digital equivalent of scan lines is screen door effect. A lot of guys in that thread state that they can see SDE at 1.5 times the screen width. They want to sit at 1.3 times the screen width so for them they feel the upgrade is worthwhile.

I can say that I see a big difference when running my PJ at 720P as opposed to 576P but I can’t see a difference between 720P and 1080i (my PJ won’t do 1080P) but this probably has more to do with the fact that my poor little 7”ES unit is running out of bandwidth and raster at the higher resolution and the fact that I haven’t had a chance to test it with HD sources.

What this really does bring home though is that if there is only a marginal difference in visible quality between 720P and 1080P, then there really isn’t going to be a difference at all between 2.35 material shown on a 720P Anamorphic setup and a conventional 1080P one. After all, a 720P in this mode is the equivalent of 960P anyway.

I think you’ll find in my original post that I stated that my personal opinion was that for those with an existing top notch PJ like the 8720, I would think that investing in a CIH setup would be more beneficial than forking out for a new 1080P model.

For those that don’t have a PJ yet or are replacing an older unit, they may get more of a benefit by going to one of the newer 1080P models. Why? Because it’s not just the resolution that has improved. In the LCD models the D6 panels are reported to have a native contrast ratio around 3 times that of the previous D5 720 panels. They are also inorganic which supposedly makes them immune to degradation. And look at the native CR of the new JVC. 15,000:1. Resolution isn’t everything and the new 1080P projectors have a few more tricks up their sleeve than just more pixels. The one exception to this may be if your looking to run a really big screen. Then it may be worth looking at one of the brighter 720P units (even a 3 chip DLP) and doing CIH with it.

Anyway, thanks for the thread. It was a great read. It actually makes me feel a lot better about running my existing PJ at 720P with BRD/HD-DVD for a while when I get home in that I probably won’t be missing out on much. Then again, did you see how many of those guys at the Greek meet were wearing glasses? 1/60th degree visual acuity? I think not!"

I still stand by most of that today.

Here's the DTV Thread where we discussed all this:

1080 vs 720

Reading that discussion makes me long for the good old days. Why can't we have a rational discussion like that these days? Must be the Hillbilly factor 'eh Foggy?

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Thanks for the info Preach, appreciate it!

I have to be quick here, but if one was to use a 720P projector, apart from say these entry level machines like Z5, AX200, TW700, HD70 etc.. and be happy with it's performance against say a TW2000 or a HC6000, how much would one be spending and would it be worthwhile if the price turns out to be say $1,000 less?... or can I expect to pickup a 720P projector for half the price of a 1080P machine and be happy with it's performance, enough to not warrant purchasing a 1080P machine? We would have to go DLP correct? If not what LCD 720P projector would one purchase to rival a 1080P LCD? They seem to be ripping the good gear out of these 720P machines these days...

Richard, I'm sure you're more familiar with how the new 1080P's stck up against the old D5 720P LCD's. The new 1080P's should significanlty outperform them. But this is laregly due to the fact that development on the 720P models stopped 2 years ago while the other's continue to move forward. I just think it's wrong to solely attribute the improvements in PQ of the 1080P LCD's over their 720P predecessors to the extra pixels. There's a lot more happenning here than just resolution.

What would be interesting would be to compare a quality 720P DLP like the Marantz 12S4 with the new 1080P Epsons and Sanyo. The Marantz is available (B stock) for about USD$2600 these days which is fairly comparable to the 1080P LCD's. For mine I'd take the Marantz but it is purely an emotional thing as I haven't seen any of the models we're talking about.

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Richard, I'm sure you're more familiar with how the new 1080P's stck up against the old D5 720P LCD's. The new 1080P's should significanlty outperform them. But this is laregly due to the fact that development on the 720P models stopped 2 years ago while the other's continue to move forward. I just think it's wrong to solely attribute the improvements in PQ of the 1080P LCD's over their 720P predecessors to the extra pixels. There's a lot more happenning here than just resolution.

What would be interesting would be to compare a quality 720P DLP like the Marantz 12S4 with the new 1080P Epsons and Sanyo. The Marantz is available (B stock) for about USD$2600 these days which is fairly comparable to the 1080P LCD's. For mine I'd take the Marantz but it is purely an emotional thing as I haven't seen any of the models we're talking about.

Oh look I agree it's more than pixels. But the fact is, like you have just said, they are not really improving 720P projectors, instead still selling yesterdays technology. That for me is yet another reason I would go 1080P over 720P.

I have no doubt that the optics of machines like the marantz and even the old benq 8720 would stack up well against some of these 1080P lcds machines, be it at a reasonable distance from the screen.

When one does NOT have 8720s and 12S4 models to compare to, the big standout advantage of these 1080P machines is the resolution when comparing against machines like TW700 and Z5's etc. Sure the optics, colours and depth of the image are also far better on these 1080P machines which is why a Marantz or an 8720 would indeed stack up better than the other cheaper machines. No argument there.

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If we were to compare 720p DLPs against the 1080p LCDs, you cannot simply choose any DLP as a lot of them are horrendous. I am talking the likes of Benq 8720 or the Optoma H79 or HD7100 (which I have seen only 2 times) but it blew me away, so mainly I am talking DC3 projectors. Firstly they blow the 720p LCDs out of the water and 2ndly against 1080p LCDs they get left behind too. Again I emphaise dont look at specs on paper have a look at pq yourself. Has anyone asked themselves why DLP and DILA 1080p pjs are so expensive and why 1080p lcds are so affordable?

There should really be a 3rd party institution where contrast ratio is measured in a standardised fashion

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If we were to compare 720p DLPs against the 1080p LCDs, you cannot simply choose any DLP as a lot of them are horrendous. I am talking the likes of Benq 8720 or the Optoma H79 or HD7100 (which I have seen only 2 times) but it blew me away, so mainly I am talking DC3 projectors. Firstly they blow the 720p LCDs out of the water and 2ndly against 1080p LCDs they get left behind too. Again I emphaise dont look at specs on paper have a look at pq yourself. Has anyone asked themselves why DLP and DILA 1080p pjs are so expensive and why 1080p lcds are so affordable?

There should really be a 3rd party institution where contrast ratio is measured in a standardised fashion

The 8720 was $10,000 when it came out but dropped to around $4,000 2 years later.

So they're expensive yes, but were they losing money when selling them for 4K? I think not.

What then is the point in comparing the 8720 to anything? It's not available anymore!

A pointless comparison don't you think? How does that help anyone recommending a projector that's been out of production for around 18 months?

So what current 720P DC3 projectors are available that are 1. better than ALL these terrible 1080P LCD machines

and 2. Much cheaper to make it a worthwhile venture.... Local prices please and current models.

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Hey Manphibian you are back :D

Can i have my shiny new PJ now please?

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I do smell Blownpixel... or DaveLR from the US has migrated?

For me to prefer a 720p projector over a 1080p projector, the 1080p projector would have to be .. a Benq or an Epson (joking)

Seriously thought - it would have to be a flawed 1080p, 1st generation of a poor brand. One of the $1500 Dim Sums on eBay.

When I look at the PQ of the VW200/60 (or even the VW50) vs any "high end" 720p projector the difference is pronounced.

The answer (of course) is CRT :)

hehe

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OMG the brown one is back...

Maybe just a flying visit. :unsure:

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I think he's currently between suspensions. ;)

Well I was right then it will be a short visit. :ph34r:

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