Difference in monitor vs projector displays

[Barry Beckham]

Peter

I don't think anyone was suggesting the that PTE was the fault was they?

In addition the fault for me occurs with a desktop. which has more than adequatre spec for PTE

I think it is something to do with the animation and the way Projectors work.

You can't have a situation where a PC runs an animated slide show perfectly, but doesn't through a projector and point to the graphics card. If it can handle the monitor it should handle the projector.

[fh1805]

Barry,

I'd be inclined to agree with you 100% but for one thing: I make one change on the Fujitsu laptop and something that didn't work correctly now does. I make an apparently identical change on the Acer laptop and it has no effect.

My hypothesis is this:

- on the Fujitsu there is an actual change in the way the graphics card and/or drivers are working to deliver the signal to the laptop monitor

- on the Acer it simply shuts off power to the LCD without changing the way the graphics card and/or drivers are working

Therefore, on the Fujitsu we see a change in behaviour of the projector whilst on the Acer we see no change in behaviour.

I'd welcome comments from you or anyone else.

BTW you seem to have duplicated a post higher up this thread (#24 and #25 look the same)

regards,

Peter

[JRR]

Thx Peter

I am quite happy to recognize that as software gets more sophisticated, we need to keep our hardware current. No problem with that.

The frustrating thing here is that we don’t know (yet ?) what we need to upgrade to what to enable us to project what I would think is a basic normal pan and zoom (that goes outside the original display portion).

In the past we seemed to know what hardware we needed to update

Again Peter, thanks for your assistance and time !!

[Guest Yachtsman1]

I think it needs someone more technical that me examine the specs of the two projectors mentioned. They are both classified as "Home Cinema" projectors with the facility for AV shows as PTE. One of the biggest UK projector retailers suggest that there is a difference from Home Cinema spec to AV spec, to the detriment of AV. This factor could have a big influence on what people buy in the future.

Yachtsman1.

[fh1805]

Eric,

Could you post a link to that website, please? So that everyone can read the information.

regards,

Peter

[davegee]

Peter,

When the Fujitsu is in the "both" configuration, the graphics card is obviously sending a signal to "both".

Could that be "overloading" the graphics card? Did you not say that the Fujitsu was the oldest with the least RAM?

(You are probably ahead of me!!)

DaveG

[fh1805]

Hi Dave,

Yes, you are quite right, the Fujitsu is the oldest of my three PCs (bought in 2004) and is the lowest spec'd of the three. It had to be pensioned off in 2007 when I discovered that it couldn't handle the PZR effects of PTE v5 in a smooth manner. Now that I've discovered that it can handle some PZRs if I change from monitor+projector to projector-only I can think of it as a "last resort" backup to my Acer.

So some good has come out of this investigation (at least, for me!)

regards,

Peter

[Guest Yachtsman1]

Eric,

Could you post a link to that website, please? So that everyone can read the information.

regards,

Peter

Hi Peter The company is Projector Point, there is a link on the thread where Tony was asking for advice on which projector to buy. However, being as it's you I've dug out the link straight to the relevent page

Regards Eric

http://www.projectorpoint.co.uk/home-cinem...tors-advice.htm

[JEB]

Hi,

I had a look at this post several days ago and downloaded the test PTE show meaning to run it on my set up which is a Canon SX50 and HP Pavilion with a GeForce Go 7600 which has 256 MB.

Only this afternoon have I had a chance to run the show. I ran it three times and took notes only on the 2,3 runs.

All I detected were minor blips on some of the pans 4 on the 2nd and 6 on the 3rd run. I have to say these were MINOR. I suspect most people would probably not notice unless asked to look for them. I did NOT get the problem you were describing. By blip I mean a VERY SLIGHT stutter. I should also say that these occurrances did not happen on the same slide on these two runs.

Hope this is of help.

I trust this is still relevant as I have not read the progress on this topic since I downloaded. It all looks a bit techie and daunting to me!!!!

Regards

John

[JRR]

John:

Thanks for the report.

Glad you had access to a Canon Sx50. The issue on the Canon certainly is less than on the Panasonic and we found the Canon issues to be intermittent (there 50% or more) whereas the Panasonic was constant.

Yes it is too techie for me too!

Thx again

[Barry Beckham]

Peter

If, your right, what are you suggesting gets changed on a desktop to avoid this problem?

B

[fh1805]

Barry,

I think the solution is out of our (the users) hands. I believe that the problems are caused by the design of the hardware and/or the design of the software drivers; and not by anything that we have done in using the equipment.

The only way I can see to avoid hitting these kinds of problems is:

- to identify a selection of sequences that are know to "stress-test" the graphics and copy them to a USB memory device

- if buying a computer, take our projector along

- if buying a projector take our computer along

- whichever we're buying, take the USB memory along

- insist on running all sequences through the proposed computer/projector pairing

If the sequences run totally free of any problem, then buy: if they don't, the equipment has failed the "acceptance test". Caveat emptor!

But, of course, the next sequence we build might be the one that shows up the hidden weakness of our pairing. We're "on a hiding to nothing" as they say!

regards,

Peter

Footnote: For those who are not conversant with Latin phrases, "Caveat emptor" is usually translated with the meaning "Let the buyer beware". It is our responsibility, as the buyer, to be certain that what we buy will do the job we want it to do. Therefore, if we want it do something very specific, we should tell the seller and seek their agreement to this specific point. Under UK Consumer Law, verbal agreements form part of the legal contract of purchase.

[Barry Beckham]

Peter

Not very practical advice? The reason will come out in the wash one day when we least expect it

[davegee]

It is possible that Maureen's comments here:

http://www.picturestoexe.com/forums/index....&hl=maureen

...about the Alienware laptop being built to match the Optoma 1920x1080 projector might be relevant and a lesson for future reference?

DaveG

[nobeefstu]

Ive been somewhat following this topic.

I have never used a projector and really dont know anything about their technical specs and requirements.

But in all this trouble-shooting discussion. I have not seen any mention any various methods of hookup, cables, and connections used between the equipment.

However, I do know in many situations when a fault in the hardware between multiple pieces of equipment cannot be so easily found ... then its time to look at the cabeling and connections used to transmit the signal. Cables and connections that dont fully meet the specs and speed requirements to properly transmit your analog /digital signal can sometimes be your limitation factor.

[Barry Beckham]

You would expect the cables supplied by the PC projector manufacturer to be adequate for the job.

Its probably one of those weird things we experience when we all do a similar thing (Digital AV) but with literally hundreds of different makes and models of kit. Sometimes for reasons we never fully discover, the equipment we hook up just doesn't go according to plan.

[Guest Yachtsman1]

Ive been somewhat following this topic.

I have never used a projector and really dont know anything about their technical specs and requirements.

But in all this trouble-shooting discussion. I have not seen any mention any various methods of hookup, cables, and connections used between the equipment.

However, I do know in many situations when a fault in the hardware between multiple pieces of equipment cannot be so easily found ... then its time to look at the cabeling and connections used to transmit the signal. Cables and connections that dont fully meet the specs and speed requirements to properly transmit your analog /digital signal can sometimes be your limitation factor.

Hi Stu

You are quite correct, I did a check on VGA extension leads and was advised not to exceed 5 metres. This distance could be exceeded in a class room situation where the projector is remotely (ceiling) mounted. How the random users PC is connected in this situation needs to be thrown into the pot. I have a 5 metre extension to connect my laptop to the TV and have no problems, I've also used it to connect the projector with no problems. However saying that there was a guy doing a show at our club a couple of weeks ago using an 8 metre lead. He had no problems but he didn't use any animation.

Regards Eric.

[Ed Overstreet]

First, I'd like publicly to thank Peter for all his work and the very useful results he got.

Peter is the only person so far who has done a well-controlled test of our sequences with two different computers on the same projector, same cable, same tests, same everything else, and has obtained results that shed a little light on the problem. One setup worked; the other didn't. That's pretty suggestive, and extremely helpful (at least in pointing to the general area where the problem likely lies).

As I understand it from Peter's post and private emails to us, the one configuration of Peter's that did work had the oldest, lesser-powered graphics card, a card that at 64 mb of video memory has only half what Jim's and my laptops have and only one-quarter of what our club's desktop computer has. All three of the latter systems use video cards that heretofore have been considered "good" or better for PTE 5.x.

This tells me that the problem likely is not the video card, certainly not the amount of video memory, though it may have something to do with drivers, or (heaven forfend!) an interaction between those elements and other as-yet-unidentified hardware or software components on the operating systems. (I say this having recently fixed a vexing keyboard problem that turned out to be caused by a not-very-necessary utility in my Startup menu that my DVD-movie playback software put in there during an upgrade; why a utility for movie playback should have any effect on my keyboard is utterly beyond me, but that's one of many reasons why I don't like Windows operating-system debugging -- the problem could be coming from almost anywhere, and from places utterly unexpected and illogical, at least to my mind.)

Peter's tests convince me the problem is something, likely not very easy to find, that one of his laptops has (or doesn't have) running that his other computer (and Jim's laptop, my laptop, Jim's desktop and the club's desktop) don't have (or do have).

That's the only explanation I've seen, either in our tests or on this forum thread, that makes any sense to me. I have a couple of tentative ideas of a small amount of further exploration that Jim, Peter and I might do that I'm going to share with them by email, though I well know what a mind-numbing and time-wasting task it is to try to ferret out obscure hardware or system conflicts in Windows. But I'm willing to try one last quick-and-dirty attempt at that.

If we learn anything from this, I'll report it on this forum. If by some miracle either Panasonic or Canon tech support come up with a "magic bullet" (I'm not holding my breath), I'll report that.

Otherwise, Jim and I are throwing in the towel and resolving to steer clear of O&A effects in our shows intended for projection, or at least restrict ourselves to a very narrow range of very conservative animations, until someone comes up with a compelling and convincing explanation for what the problem really is and a clear and hopefully not-too-expensive fix for it. That hasn't happened yet.

Thanks everyone for all your help and suggestions, but honestly at this point I'm crying "uncle" and getting on with other things in my life.

Oh yes, and thanks very much Barry for letting us know that you've been aware of these problems for some time and were getting them on a very-well-equipped desktop. Misery loves company, even when the misery doesn't really solve the problem.

[cjdnzl]

Well, the towel's in the ring now, having been thrown there by Ed, but I have one other idea which doesn't seem to have been explored. I touched on it some posts back when I asked if a composite video ( S-video) connection to the projector had been tried, and I haven't seen the outcome of any trial to that end.

Now, I may be up a gum tree here, but looking at video cards from a gaming point of view, one measure the gamers use is frame repetition (refresh) rates, and how many refreshes per second a particular card delivers with various games; some games are extremely heavy users of the gpu, and the refresh rate slows unacceptably.

This indicates to me, at least on the surface, that the amount of data crunching required for a game, or in our case PZR, will affect the refresh rate. If so, then expecting a projector to cope with a constantly varying refresh rate throughout a show (fast with static images, slower with PZR effects) is maybe asking too much of the projector.

Perhaps Igor could give us some idea of how refresh rates behave with varying PZR demands on the gpu. I might try to use some of the gamers' test programs on PTE shows and see what happens.

Colin

[LumenLux]

I might try to use some of the gamers' test programs on PTE shows and see what happens.

Colin

I would welcome that effort Colin. I will look forward to tagging on to what you observe.

[xahu34]

Hi,

Tonight I ran one of my test sequences on a Canon SX60, a sequence of 8 short zooms, followed by a 360 degree panorama running 45 seconds. I ran the sequence several times without any flaw. I created the sequence several months ago, in order to test the Canon SX50, which showed sporadic effects on the zooms, and in all cases effects about any 12 seconds during the panorama. The effect was tearing (http://en.wikipedia.org/wiki/Screen_tearing), which Ed seems to call a wipe effect. As a final remark, let me say that I used for both projectors the same PC with an Nvidia 8500GT.

Best regards

Xaver

Munich

[LumenLux]

Xaver, your comment and the link both add additional good information. I think eventually all the pieces will come together and at least some of us will understand it all. Perhaps the most likely conclusion will be that there is very little we can do to "solve" the issue. That will probably be about the same time that the projector makers will provide us with a new option - which we all will recognize - more money will then buy a new projector that will overcome the issue.

[Conflow]

Colins Post #44 above

Hi Colin,

Indeed I remember your original post on this problem, and yes you are on the right track, and to be honest

I had forgotten all about this problem until I read the entire contents of this thread. It's very difficult to give an

explaination for the 'sources' of what appears to be a 'common problem' but in reality it's a common visual

manifestation which can arise from many sources....."a matter of cart before the horse"

For the purposes of debate let's keep this simple and firstly let's establish a few common facts:-

Digital Projectors

1) These machines are so different to the older Analog Projects (3M-Carousel) it's like chalk and cheese.

2) These Projectors are designed to handle Television-Video Signals...without the Transmitter and certain Avi's.

3) Television-Video such as PAL, NTSC, and Secam are "streaming signals" processed by the Projectors Video-Processor.

4) Streaming-Video has little need for internal Memory-Buffer capacity consequently most are about 4~8.Megabyte size.

5) All the "Synchronising-Timing" is contained within the Television-Video signal whether live or from a DVD.

6) These synchronising-pulses keep the internal Video-Processor "locked" to the stringent standards of PAL and NTSC.

7) The Projector is contineously "Re-Drawing" and "Re-Freshing" the projected image at 25.fps (Frames per sec).

8) Its 'Memory-Buffer' is designed to handle this workload, but you can not see this 'redrawing' on the Projector Screen.

Your Computer

a) As I said the Projector will handle "Still-Images" within the usual formats of VGA, XGA, etc,etc...

These 'Still-Images' will rarely exceed the internal Memory-Buffer capacity of your Projector.

c)

However when you start using Pan & Zoom which are "Motion-Images" non-synchronised and non-streaming at very

high Frame-Rates often in excess of 60.Fps (PC Standard) this will completely overwhelm the Projector-Memory leading

to pixellation, image-banding, colour-bars, jerking and who knows what !!

d)

Yes there are exceptions

* Some really good Projectors which can apply 'interlaced re-scanning' of the Motion-Image which reduces pixellation.

* Semi-Pro Projectors designed for Commercial Conference Work often with Buffer-Memory exceeding 64.Mb.

* Some 'older PCs' whose VGA output is much lower than 60.Fps and some whose VGA is running at low Buss-Speeds.

Summary

* Projectors are designed to handle (at best) some 25-30 Frames per second ~ you are throwing 50-60.Fps at it !!

* Projector memories are very small, (approx) 4/8 Mb ~ you need a minimum of 16.Mb to get stable PZR.performance.

* When using PZR try and reduce your PZR Scans times below 5.secs for Lo-Cost Projectors.

* When choosing a Projector try to acquire a Model which has independent Vert/Horiz Inputs (Twin input Home-Cinema type).

* If possible try and purchase a Model which has 'Interlace-Redraw' facilities.

* Most Important try and re-adjust your VGA-output down to 25/30 Fps....take the load off your Projector !

This explaination is by NO MEANS exhaustive but simply attempts to identify the most common operational problems with

most low-cost Projectors ~ good ones still cost + $1500.

Hope this helps and below is a 'quik-spec' as to Projector signal inputs.

Brian.Conflow.

[JRR]

Brian:

Appreciate your simple but thorough explanation.

What has us (me anyway) stumped is why, in out tests anyway, this is only an issue on zooming outside the original portion of the image. Zoom inside the original portion and all is OK. Pans of course by definition take you outside the original portion and thus are problematic

[fh1805]

Brian,

I go along with Jim in thanking you for your clear and concise explanation of what is obviously a very complex technical subject.

However, one aspect of this problem that isn't, as far as I can see, obviously addressed by your explanations is this: why does my old Fujitsu laptop only exhibit the problem if I run it with both the monitor and the projector active at the same time?

- Monitor on its own - no projector attached = no problem

- Monitor and projector both operating together = problem

- Use the Fn key to toggle off the monitor, leaving just the projector operating = no problem.

I would have naively thought that the signal going to the projector would be the same in all three cases - but clearly it isn't.

Can you offer any enlightenment, please? (The pun wasn't intended but having written it I couldn't resist the play on words!)

regards,

Peter