Official JVC - 20LTD - RS640 (x990/x9900) - RS540 (X790/x7900) - Owners Thread - Page 275 - AVS Forum | Home Theater Discussions And Reviews
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post #8221 of 13257 Old 08-25-2018, 08:01 AM
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Originally Posted by Dominic Chan View Post
What’s “reasonable” depends on familiarity and feasibility. One could say it’s reasonable to expect the picture brightness spec to apply to the whole screen, but in actual fact the corners are always less bright, by 30, 40 or 50%, and no one would claim that’s a defect.

Judging by the recent posts in the JVC forums, most people seem to have accepted that it’s “reasonable” to have the paper test showing brighter corners.
It seems less "reasonable" if you already had a £6K projector devoid of brighter corners, only to have it replaced with one with them... . The difference is not slight between the units. And while many folk understand lens vinetting etc - those tend to be much more constant, design specific matters which do not vary to such a degree from unit to unit. We're talking about 5-6x less native contrast at that corner area than in the lens centre at worst case iris settings.

Of course my "good" unit has an erratic lens iris, but I doubt very much that is much implicated as no matter the iris setting on the "not so good" unit it doesn't make any useful improvement to the contrast of those areas.

At the end of the day once the screen goes up in my room I'll be able to see it in all it's glory. It looks like the contrast in at least one corner is around 20,000:1 regardless of iris; if I set the iris to get my 56cd/m2 this means the black level I end up seeing at the edges (they're clearly not just corners) will probably be something like 0.004-0.006nits instead of <0.001 nits in the centre of the screen. Most of the time it won't be visible due to eye bias, but it will be visible to the naked eye easily. I'll be interested to see what starfields make of it. Probably the seemingly better convergence will make more difference to the image quality for me than the black field uniformity.

I'm not aware that I'd seen anyone measure the contrast in those areas before; but it does sound like we're setting ourselves up as apologists for poorer than expected contrast before the new 4K units have even arrived... . I mean, how far do poor contrast areas have to extend into the frame before you start questioning what is the contrast ratio really achieved? And I really do think that we should start talking about what is a reasonable way to talk about contrast on product.

Interesting thoughts and questions which could only really be discussed in the presence of either user data or an open discussion policy by JVC on the details of the phenomenon:

Are the 4xx units likely to have better black field uniformity due to less pushing of the envelope for contrast?
Are the 6xx units likely to have better black field uniformity due to hand picked parts (maybe I got panels that could have gone in a 6xx in my first unit, but they didn't need them so they went in a 5xx).
How likely am I to have corners with these issues vs not? (I've got a 50% hit rate at the moment).

I'm a bit disappointed that the attitude is generally "it is what it is". For my own part looking at this with my "production test" hat on - I think clearly I've demonstrated there are good (at least 1) and not-so-good units out there. It's completely measurable. It would be possible to devise simple tests (took me minutes) to measure these optical blocks for the phenomenon.

The testing is either being done at the factory already (and these units are passes - in which case we could be told what the test limits are); or the units passed some stricter criteria in the factory and something has happened to them since (misalignment due to shipping /packaging, rapid degeneration, insert random theory here); or they simply aren't tested in this way. In all cases it should be possible to have an open understanding of what exactly it is you are buying into at 130,000:1.
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post #8222 of 13257 Old 08-25-2018, 08:13 AM
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Originally Posted by bobof View Post
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Are the 4xx units likely to have better black field uniformity due to less pushing of the envelope for contrast?
I believe so. If the RS4xx units had the issue to the same extent, we would be looking at a contrast ratio of ~2000:1 near the corners, which would be very obvious and yet I haven’t heard any such complaints.
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post #8223 of 13257 Old 08-25-2018, 08:26 AM
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Originally Posted by Mike Garrett View Post
"They'll be the same throw within a couple of inches." That is one of my points. Throw makes a huge difference. If one is at 2" and the other is at 4", then how can you compare? Even going from 4" to 6" you are 1.5 times the throw. I found a huge difference on the same projector, just by changing the distance a little bit. As I said, if you use the same procedure and the same piece of paper, the test will tell you something, but you can't compare, if not done the same way. Also as has been brought up, the projector is not designed to focus at such a short range.
I've already explained why it is hard to take a photo in exactly the same position due to the physicality of the units and their locations. The "good" one doesn't look anything like the "less good" one.

On either of these units you can put the paper wherever you want - you'll see a huge difference between the shading on each. It is extremely obviously different.

To answer your question on numbers; for your reference the projected width in these pics is 250mm wide - as I said I marked out a rectangle on the paper (you can see it in the photos if you look carefully...) and attempted to hit that while balancing to take the pic for the good unit. You can work out what that means in terms of lens throw given the lens throw multiplier... it's no-where near the ranges you are talking about.

For the not-so-good unit there was no difficulty hitting the frame as it is on the upturned JVC box on the floor.
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post #8224 of 13257 Old 08-25-2018, 08:43 AM
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Originally Posted by bobof View Post
Are the 4xx units likely to have better black field uniformity due to less pushing of the envelope for contrast?
Are the 6xx units likely to have better black field uniformity due to hand picked parts (maybe I got panels that could have gone in a 6xx in my first unit, but they didn't need them so they went in a 5xx).
How likely am I to have corners with these issues vs not? (I've got a 50% hit rate at the moment).
The RS4XX typically have better corners because the black floor is not as low as the RS5/6XX. According to Cine4home, the issue is a result of the bonding used on the chipset. Most people are not sensitive to the corners on the upper series and the superior contrast is worth it. I am VERY sensitive to uniformity issues in general including grey as well as black. The corners on my RS440 are excellent, but I'm also only around 21,000:1 native based on my set-up and iris. However, uniformity is just too important for me and I am still happy with the contrast. But, it certainly a big step behind the contrast of RS500 I used to have.

My former RS4810 and RS4910 had very good corners too, but then their contrast level was similar to my RS440 if we're talking lumens matched. But, no LCoS/LCoQ model is immune to it. I saw a refurbed RS4910 and a new LS10000 once that had horrible corners. The corners were so bad on these units that the brightness was pushing into the center of the screen.

As far as the paper test, I would not be too concerned about it. I've had some nice corner units that still didn't look perfect on the paper test. Go by real content and low APL scenarios with your eyes on the screen.
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post #8225 of 13257 Old 08-25-2018, 09:33 AM
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Have any Harmony Hub users found a way to map a custom mask selection to a device or activity command? I see there are shortcut commands for various lens shift settings but don't see one for custom mask selection.
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post #8226 of 13257 Old 08-25-2018, 09:59 AM
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Any ideas?
Did you ever get this working. I can not for the life of me get this to work with any amount of delays. It is almost like it just doesn't send the signal
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post #8227 of 13257 Old 08-25-2018, 10:08 AM
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Originally Posted by bobof View Post
I've already explained why it is hard to take a photo in exactly the same position due to the physicality of the units and their locations. The "good" one doesn't look anything like the "less good" one.

On either of these units you can put the paper wherever you want - you'll see a huge difference between the shading on each. It is extremely obviously different.

To answer your question on numbers; for your reference the projected width in these pics is 250mm wide - as I said I marked out a rectangle on the paper (you can see it in the photos if you look carefully...) and attempted to hit that while balancing to take the pic for the good unit. You can work out what that means in terms of lens throw given the lens throw multiplier... it's no-where near the ranges you are talking about.

For the not-so-good unit there was no difficulty hitting the frame as it is on the upturned JVC box on the floor.
You are the one that said it would be the same, within a couple of inches, but there is another variable. The projector was not mounted in the same location so zoom was different between the two. I am just saying, if you are going to compare results, you have to use the same procedure. Yes, I think there will still be a difference, but I doubt the results are going to be the same as what you are showing. This is also why I say people can't compare this test and say, mine is worse than yours or yours is worse than mine. Also without knowing what would be acceptable under exact test conditions, you can't conclude anything. Better off just viewing low APL content and seeing if you see bright corners.
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post #8228 of 13257 Old 08-25-2018, 10:13 AM
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Originally Posted by Mike Garrett View Post
You are the one that said it would be the same, within a couple of inches, but there is another variable. The projector was not mounted in the same location so zoom was different between the two. I am just saying, if you are going to compare results, you have to use the same procedure. Yes, I think there will still be a difference, but I doubt the results are going to be the same as what you are showing. This is also why I say people can't compare this test and say, mine is worse than yours or yours is worse than mine. Also without knowing what would be acceptable under exact test conditions, you can't conclude anything. Better off just viewing low APL content and seeing if you see bright corners.
How does PJ location affect zoom?
I set both to full zoom and moved the paper to the PJ...

Edit:

Quote:
Originally Posted by bobof View Post
Here are two pics. One is the "good" unit, one the not so good. both fully open, full zoom, paper has a rectangle marked on it to roughly fill the same area, I'm having trouble hitting the spot balanced on one leg, but it is there abouts. Not so good is "right way up", good is ceiling mount. The only significant issue on good is the green area which is outside the image area, must be some reflection inside the unit. This area is also on the bad (opposite corner due to PJ orientation) but it isn't as noticeable because of all the other issues drowning it out.

The framing is awkward because I'm balanced on a sofa in the dark, but you can see how different the two are. They'll be the same throw within a couple of inches. These are quite representative of how it looks in real life luminance wise, and the comparison is not extreme; you should probably ignore the colour temp as the camera's auto white balance is reacting differently to each frame. But I think the level of difference in the shading in the frame is really quite clear. I can't safely operate the good camera in this environment, so it is what it is.
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Last edited by bobof; 08-25-2018 at 10:19 AM.
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post #8229 of 13257 Old 08-25-2018, 10:20 AM
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I have the X790 and inputting that into the database will work to turn the projector on but not off. If you have a chance I'd appreciate it if you could check and see what projector you used in your harmony database. Thanks
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Choosing DLA-X7900 definitely works for my setup, try that.
EDIT: Mine is actually set to DLA-X790R. D'oh. Check your power settings look something like the attached.
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I just checked. I am using RS600. I used to have an RS600. Then went to RS4500 and now I am using RS640. I don't think the 640 was listed in the database at the time I did the setup.
Well I checked my power off sequence and set it like bobof's screen shot and tried both the X790R and RS600 as the projector and could always get it to turn on but never off. I tried probably 20 different power sequences with delays with no luck.

I am using the remote to turn the projector on and off as I do not have a blaster in my theater room. It is almost like the off signal is never being sent to the remote. I put in delays to shut off my receiver and Shield TV and never saw the off prompt come up on the screen to turn the projector off before the rest of the system shut down.

It has me a bit confused as I am able to go into the device setting on the Harmony remote and turn off the projector after everything has shut down.
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post #8230 of 13257 Old 08-25-2018, 10:20 AM
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My point is specs are not very meaningful, unless the measurement conditions are spelt out.
That is a very true statement.
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post #8231 of 13257 Old 08-25-2018, 10:40 AM
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Originally Posted by bobof View Post
How does PJ location affect zoom?
I set both to full zoom and moved the paper to the PJ...
Projector zoom, if different will change the results of the test. Once again, since no established procedure, I have no idea how you performed the test. I did know that you did not have the two projectors in the same location, but did not know what you had done for zoom or focus.
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post #8232 of 13257 Old 08-25-2018, 11:34 AM
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Projector zoom, if different will change the results of the test. Once again, since no established procedure, I have no idea how you performed the test. I did know that you did not have the two projectors in the same location, but did not know what you had done for zoom or focus.
I did say full zoom and fully open for the iris in the message accompanying those photos. I think you just missed it.

In any case, as I say I'm actually much more interested in real, measurable results that folk can compare without howls of invalid test; that way we can push product forward through detailed understanding, and sensibly compare... As I said in following messages, all suggestions on what constitute repeatable, meaningful measurements for the purpose of exploring the black field uniformity on these projectors are welcome. What do you suggest?

As I said further up; I quickly measured the native contrast at the centre and in the brighter area at around 18ins throw full zoom and there is a huge difference between the measured contrast in the centre of the frame and in the "cloudier" region of brighter corner (to be expected given what the paper looks like). Now unless there is some optical magic going on (I doubt it ) I'm sure the same contrast difference will be measurable at real screen throw distance (I just can't get that far away from the less good projector at the moment).

I think it is really interesting coming up to the potential launch of new 4K product.

To give you an example of why.

A lot of folk are up in arms at the moment that 4K units won't achieve the same native contrast.

If as the undertone of what you're saying would seem to indicate the "not so good" unit I have should really be re-labelled "typical" - fine, that is the current state of play - I've only seen two units so I'm not going to argue. From quick measurements I would say this Typical unit looks like it might achieve 60-80K:1 at the centre for my typical iris setting but falling off very rapidly to the bright sides/ corners where 20K:1 is measured. At this point, do you think it is reasonable to use the centre contrast rating as your basis for comparison if a typical unit doesn't achieve this contrast over most of the field?

Say we end up with 4K units that are sat at around 40K:1 with iris, but detailed measurements show that improvements have been made and they tend to me more uniform in their black field. It's quite within the realms of possibility that the average contrast experienced over the whole frame is very similar or even better on the 4K unit than on the "typical" 1080p eShift, if a typical 1080p isn't uniform. The overall contrast experience in the whole frame may end up being better due to this.

So please, ignore the pointless too and fro trying to nitpick at the paper photo comparison I put up (even though they are representative - but unless you do the test yourself on these two units I doubt you'll believe it) and suggest what you think would be useful ways to measure the black field performance. I made a suggestion above. Comments welcome

We should be able to come up with good representative test (and then data) which shows what kind of contrast a purchaser of a projector will experience across the frame of their image at various settings. This information can help consumers make informed purchase decisions and educate arguments over what contrast is really experienced.
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post #8233 of 13257 Old 08-25-2018, 12:01 PM
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Well I checked my power off sequence and set it like bobof's screen shot and tried both the X790R and RS600 as the projector and could always get it to turn on but never off. I tried probably 20 different power sequences with delays with no luck.

I am using the remote to turn the projector on and off as I do not have a blaster in my theater room. It is almost like the off signal is never being sent to the remote. I put in delays to shut off my receiver and Shield TV and never saw the off prompt come up on the screen to turn the projector off before the rest of the system shut down.

It has me a bit confused as I am able to go into the device setting on the Harmony remote and turn off the projector after everything has shut down.
Which remote to you have?
If on the remote you go to "Devices" and select the projector and press "Off" "Off" does it turn off correctly?

Two possibilities I think.
One is that it is sending the power off to the projector but the projector is ignoring it. JVC units sometimes do this if the HDMI input is changing while you try to send the off commands. So if your AVR or video player turn off or trigger a refresh rate change or similar just before the harmony attempts to shut down the projector the shutdown codes may get ignored. You can see this yourself by using JVC's own remote to try and shut down immediately after shutting down a connected AVR or similar manually. You might find it ignores the remote.

The other which I've sometimes seen is a corrupted device / activity. Delete the projector, add it back, and then create a new activity which has the projector in and see if that activity works. If so you might have to re-create all your activities.
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post #8234 of 13257 Old 08-25-2018, 12:23 PM
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Which remote to you have?
If on the remote you go to "Devices" and select the projector and press "Off" "Off" does it turn off correctly?

Two possibilities I think.
One is that it is sending the power off to the projector but the projector is ignoring it. JVC units sometimes do this if the HDMI input is changing while you try to send the off commands. So if your AVR or video player turn off or trigger a refresh rate change or similar just before the harmony attempts to shut down the projector the shutdown codes may get ignored. You can see this yourself by using JVC's own remote to try and shut down immediately after shutting down a connected AVR or similar manually. You might find it ignores the remote.

The other which I've sometimes seen is a corrupted device / activity. Delete the projector, add it back, and then create a new activity which has the projector in and see if that activity works. If so you might have to re-create all your activities.
I have the Harmony Ultimate.

If I go to devices I can shut off the projector.

I tried putting a delay in for shutting off the receiver and shield of about 6 seconds and setup the JVC to shutoff first but no go

I also tried making a new activity from scratch with no luck. This is a weird one and not sure why it won't work.
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post #8235 of 13257 Old 08-25-2018, 12:28 PM
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I have the Harmony Ultimate.

If I go to devices I can shut off the projector.

I tried putting a delay in for shutting off the receiver and shield of about 6 seconds and setup the JVC to shutoff first but no go

I also tried making a new activity from scratch with no luck. This is a weird one and not sure why it won't work.
I have Harmony Elite and have same issue. If turn off via devices and press off twice works. I have Logictec look at it and they did something however when trying from activity works like 50% of the time.
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post #8236 of 13257 Old 08-25-2018, 12:31 PM
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I have Harmony Elite and have same issue. If turn off via devices and press off twice works. I have Logictec look at it and they did something however when trying from activity works like 50% of the time.
Maybe I will contact Logitech on the issue. I think the reason it is not working is because the signal is not being sent properly through the activity.
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post #8237 of 13257 Old 08-25-2018, 12:36 PM
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Maybe I will contact Logitech on the issue. I think the reason it is not working is because the signal is not being sent properly through the activity.

If do tell them look at my case might help

Projector not turning off [07214591]
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post #8238 of 13257 Old 08-25-2018, 01:12 PM
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I think it is really interesting coming up to the potential launch of new 4K product.

To give you an example of why.

A lot of folk are up in arms at the moment that 4K units won't achieve the same native contrast.

If as the undertone of what you're saying would seem to indicate the "not so good" unit I have should really be re-labelled "typical" - fine, that is the current state of play - I've only seen two units so I'm not going to argue. From quick measurements I would say this Typical unit looks like it might achieve 60-80K:1 at the centre for my typical iris setting but falling off very rapidly to the bright sides/ corners where 20K:1 is measured. At this point, do you think it is reasonable to use the centre contrast rating as your basis for comparison if a typical unit doesn't achieve this contrast over most of the field?

Say we end up with 4K units that are sat at around 40K:1 with iris, but detailed measurements show that improvements have been made and they tend to me more uniform in their black field. It's quite within the realms of possibility that the average contrast experienced over the whole frame is very similar or even better on the 4K unit than on the "typical" 1080p eShift, if a typical 1080p isn't uniform. The overall contrast experience in the whole frame may end up being better due to this.
This is a 'sticky' argument, and people want to measure them all the same.
IMO, you are correct Sir, it's not the real contrast unless it's doing it over most of the screen.
Just like ANSI Lumens are not measured from just the center, neither should contrast be technically.

However, contrast measurements are already so ripe with inaccuracies, no-one wants to measure a 9-point average every time they do a contrast reading.
That is a lot of work.

I made that point once when I measured an RS-67 which had really poor black field uniformity.
Technically, I would average ONLY half the penalty into it, since that is about all our eyes notice (our eyes do not see the full penalty).

So if you had 60% black field uniformity from the bright corners, I'd penalize the contrast rating by about 20%.

The thing is though, the white corner issues has disappeared on my old JVC projector.
The question is did the entire panel degrade into a more balanced uniformity (possibly), or is it mainly because of my mounting position changing (not sure).
Did some parts on the LCOS panel just warp into alignment better from heat over time (doubt it).

So it's a very odd issue, and I know no-one believes me when I say the problem went away, but it really did.
I mean I am not blind, you cannot even see it anymore when looking for it. When I first had my JVC, it was blatantly obvious.
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post #8239 of 13257 Old 08-25-2018, 01:25 PM
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This is a 'sticky' argument, and people want to measure them all the same.
IMO, you are correct Sir, it's not the real contrast unless it's doing it over most of the screen.
Just like ANSI Lumens are not measured from just the center, neither should contrast be technically.

However, contrast measurements are already so ripe with inaccuracies, no-one wants to measure a 9-point average every time they do a contrast reading.
That is a lot of work.

I made that point once when I measured an RS-67 which had really poor black field uniformity.

The thing is though, the white corner issues has disappeared on my old JVC projector.
The question is did the entire panel degrade into a more balanced uniformity (possibly), or is it mainly because of my mounting position changing (not sure).
Did some parts on the LCOS panel just warp into alignment better from heat over time (doubt it).

So it's a very odd issue, and I know no-one believes me when I say the problem went away, but it really did.
I mean I am not blind, you cannot even see it anymore when looking for it. When I first had my JVC, it was blatantly obvious.
True, it would be a bit of effort. But for someone with a meter it probably represents an hour of time, you find out something out about your unit and everyone wins a bit of knowledge. At the end of the day often change is driven from the outside; if you can measure it you can filter it, work on it, improve it, etc. With enough incentive product change can be driven.

Interesting data from your old unit. I don't disbelieve anything because I'm sure from reading around that it seems no-one who is talking publicly about it really fully understands what is going on here.

How many hours and lamps has it had, and did you note when you thought it changed?

What changed about your mounting?
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post #8240 of 13257 Old 08-25-2018, 01:29 PM
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Originally Posted by bobof View Post
True, it would be a bit of effort. But for someone with a meter it probably represents an hour of time, you find out something out about your unit and everyone wins a bit of knowledge. At the end of the day often change is driven from the outside; if you can measure it you can filter it, work on it, improve it, etc. With enough incentive product change can be driven.

Interesting data from your old unit. I don't disbelieve anything because I'm sure from reading around that it seems no-one who is talking publicly about it really fully understands what is going on here.

How many hours and lamps has it had, and did you note when you thought it changed?

What changed about your mounting?
I went from farthest throw to closest throw.
I saw it 'improve' a bit I think around 2000-3000 hours.

I am currently at 8000 hours and now it is gone (at closest throw).
This is on an old RS-45.

The RS-67 I saw wasn't in my own room, didn't get to mess with it much, just took a contrast reading and played around in the menus for a bit.
However, the bright corners on the RS-67 were twice as bad as my RS-45 ever was, but that might be from the RS-67 having so much higher contrast making it more noticeable.

I am likely replacing / upgrading the RS-45 after this year (maybe).
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post #8241 of 13257 Old 08-25-2018, 02:07 PM
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I did say full zoom and fully open for the iris in the message accompanying those photos. I think you just missed it.

In any case, as I say I'm actually much more interested in real, measurable results that folk can compare without howls of invalid test; that way we can push product forward through detailed understanding, and sensibly compare... As I said in following messages, all suggestions on what constitute repeatable, meaningful measurements for the purpose of exploring the black field uniformity on these projectors are welcome. What do you suggest?

As I said further up; I quickly measured the native contrast at the centre and in the brighter area at around 18ins throw full zoom and there is a huge difference between the measured contrast in the centre of the frame and in the "cloudier" region of brighter corner (to be expected given what the paper looks like). Now unless there is some optical magic going on (I doubt it ) I'm sure the same contrast difference will be measurable at real screen throw distance (I just can't get that far away from the less good projector at the moment).

I think it is really interesting coming up to the potential launch of new 4K product.

To give you an example of why.

A lot of folk are up in arms at the moment that 4K units won't achieve the same native contrast.

If as the undertone of what you're saying would seem to indicate the "not so good" unit I have should really be re-labelled "typical" - fine, that is the current state of play - I've only seen two units so I'm not going to argue. From quick measurements I would say this Typical unit looks like it might achieve 60-80K:1 at the centre for my typical iris setting but falling off very rapidly to the bright sides/ corners where 20K:1 is measured. At this point, do you think it is reasonable to use the centre contrast rating as your basis for comparison if a typical unit doesn't achieve this contrast over most of the field?

Say we end up with 4K units that are sat at around 40K:1 with iris, but detailed measurements show that improvements have been made and they tend to me more uniform in their black field. It's quite within the realms of possibility that the average contrast experienced over the whole frame is very similar or even better on the 4K unit than on the "typical" 1080p eShift, if a typical 1080p isn't uniform. The overall contrast experience in the whole frame may end up being better due to this.

So please, ignore the pointless too and fro trying to nitpick at the paper photo comparison I put up (even though they are representative - but unless you do the test yourself on these two units I doubt you'll believe it) and suggest what you think would be useful ways to measure the black field performance. I made a suggestion above. Comments welcome

We should be able to come up with good representative test (and then data) which shows what kind of contrast a purchaser of a projector will experience across the frame of their image at various settings. This information can help consumers make informed purchase decisions and educate arguments over what contrast is really experienced.
It's nice to hear some critical thought about JVC. Sometimes I feel many on this forum discard the flaws the JVCs tend to exhibit and fail to mention them/minimize their effect, with lots of disillusioned people getting back claiming their eshift was a lot less sharp than expected, their eshift unit made a lot more noise than expected, etc. While at the same time piling dirt on the Sony's to such an extent that people feel the need to become defensive.

Here's hoping we can become a little less biased when the new units roll around, and look at these machines more at face value.
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post #8242 of 13257 Old 08-25-2018, 02:38 PM
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Originally Posted by coxy2416 View Post
Maybe I will contact Logitech on the issue. I think the reason it is not working is because the signal is not being sent properly through the activity.
I use the Harmony Home Companion and Hub, and it turns off the projector without problem.

In my activity, though, I have a 30 second delay between turning off the Blu-ray player, to allow for the JVC to re-sync the connection (which typically takes 15 to 20 seconds), and then turning off the Projector. While it is in this re-syncing stage, it will not respond to any Harmony commands.

Putting this delay allows the Projector to complete its re-sync, and it will then accept new commands and turn off.

HTH.

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post #8243 of 13257 Old 08-25-2018, 02:38 PM
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Quote:
Originally Posted by bobof View Post
I did say full zoom and fully open for the iris in the message accompanying those photos. I think you just missed it.

In any case, as I say I'm actually much more interested in real, measurable results that folk can compare without howls of invalid test; that way we can push product forward through detailed understanding, and sensibly compare... As I said in following messages, all suggestions on what constitute repeatable, meaningful measurements for the purpose of exploring the black field uniformity on these projectors are welcome. What do you suggest?

As I said further up; I quickly measured the native contrast at the centre and in the brighter area at around 18ins throw full zoom and there is a huge difference between the measured contrast in the centre of the frame and in the "cloudier" region of brighter corner (to be expected given what the paper looks like). Now unless there is some optical magic going on (I doubt it ) I'm sure the same contrast difference will be measurable at real screen throw distance (I just can't get that far away from the less good projector at the moment).

I think it is really interesting coming up to the potential launch of new 4K product.

To give you an example of why.

A lot of folk are up in arms at the moment that 4K units won't achieve the same native contrast.

If as the undertone of what you're saying would seem to indicate the "not so good" unit I have should really be re-labelled "typical" - fine, that is the current state of play - I've only seen two units so I'm not going to argue. From quick measurements I would say this Typical unit looks like it might achieve 60-80K:1 at the centre for my typical iris setting but falling off very rapidly to the bright sides/ corners where 20K:1 is measured. At this point, do you think it is reasonable to use the centre contrast rating as your basis for comparison if a typical unit doesn't achieve this contrast over most of the field?

Say we end up with 4K units that are sat at around 40K:1 with iris, but detailed measurements show that improvements have been made and they tend to me more uniform in their black field. It's quite within the realms of possibility that the average contrast experienced over the whole frame is very similar or even better on the 4K unit than on the "typical" 1080p eShift, if a typical 1080p isn't uniform. The overall contrast experience in the whole frame may end up being better due to this.

So please, ignore the pointless too and fro trying to nitpick at the paper photo comparison I put up (even though they are representative - but unless you do the test yourself on these two units I doubt you'll believe it) and suggest what you think would be useful ways to measure the black field performance. I made a suggestion above. Comments welcome

We should be able to come up with good representative test (and then data) which shows what kind of contrast a purchaser of a projector will experience across the frame of their image at various settings. This information can help consumers make informed purchase decisions and educate arguments over what contrast is really experienced.
Easy way to test uniformity is once you have the projector set up, shooting onto your screen, press the hide button and see what the uniformity looks like. Now if you have to spend a minute closely examining the image to discern a difference with the corners, then you will never notice it with moving content.
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post #8244 of 13257 Old 08-25-2018, 02:40 PM
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Quote:
Originally Posted by coxy2416 View Post
I have the Harmony Ultimate.

If I go to devices I can shut off the projector.

I tried putting a delay in for shutting off the receiver and shield of about 6 seconds and setup the JVC to shutoff first but no go

I also tried making a new activity from scratch with no luck. This is a weird one and not sure why it won't work.
Do you have the Harmony turning the projector off first?
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post #8245 of 13257 Old 08-25-2018, 02:46 PM
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Quote:
Originally Posted by coxy2416 View Post
I have the Harmony Ultimate.

If I go to devices I can shut off the projector.

I tried putting a delay in for shutting off the receiver and shield of about 6 seconds and setup the JVC to shutoff first but no go

I also tried making a new activity from scratch with no luck. This is a weird one and not sure why it won't work.
Quote:
Originally Posted by Mike Garrett View Post
Do you have the Harmony turning the projector off first?
Yes I do. I have been working on the delays but haven't had any luck as of yet.
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post #8246 of 13257 Old 08-25-2018, 02:53 PM
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Quote:
Originally Posted by DLCPhoto View Post
I use the Harmony Home Companion and Hub, and it turns off the projector without problem.

In my activity, though, I have a 30 second delay between turning off the Blu-ray player, to allow for the JVC to re-sync the connection (which typically takes 15 to 20 seconds), and then turning off the Projector. While it is in this re-syncing stage, it will not respond to any Harmony commands.

Putting this delay allows the Projector to complete its re-sync, and it will then accept new commands and turn off.

HTH.
Do you put the delay in the Device or Activity. If I put the delay in the Activity it will always be the first step and I can not move it lower.
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post #8247 of 13257 Old 08-25-2018, 03:00 PM
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Quote:
Originally Posted by coxy2416 View Post
Do you put the delay in the Device or Activity. If I put the delay in the Activity it will always be the first step and I can not move it lower.
Here's a screen capture of the Activity Shutdown Commands. I first eject the tray on the player, so I can remove it, and put it away while the other stuff gets shut down.
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post #8248 of 13257 Old 08-25-2018, 03:33 PM
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Originally Posted by Mike Garrett View Post
Easy way to test uniformity is once you have the projector set up, shooting onto your screen, press the hide button and see what the uniformity looks like. Now if you have to spend a minute closely examining the image to discern a difference with the corners, then you will never notice it with moving content.
My ultimate screen width is 2m. at the moment can get throw to get to 1.3m wide, and the bright sides are still very visible. This will be about 3x the overall luminance but the contrast isn't going to change between the dark and light areas.

From my calculations from the measurements I took the difference in the black level between the centre and between the sides will be similar to going from aperture 0 to aperture -11 or so on the same screen. I'm sure you'd agree you'd have to be blind not to see that.

Let's fast forward this.
If bright corners are clearly visible in hide at real screen size what does that mean?
Bad luck, you won the bright corner lottery, enjoy my friend? or
They shouldn't be noticeable, that would perhaps indicate a unit that's not up to scratch?
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post #8249 of 13257 Old 08-25-2018, 03:43 PM
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Originally Posted by bobof View Post
My ultimate screen width is 2m. at the moment can get throw to get to 1.3m wide, and the bright sides are still very visible. This will be about 3x the overall luminance but the contrast isn't going to change between the dark and light areas.

From my calculations from the measurements I took the difference in the black level between the centre and between the sides will be similar to going from aperture 0 to aperture -11 or so on the same screen. I'm sure you'd agree you'd have to be blind not to see that.

Let's fast forward this.
If bright corners are clearly visible in hide at real screen size what does that mean?
Bad luck, you won the bright corner lottery, enjoy my friend? or
They shouldn't be noticeable, that would perhaps indicate a unit that's not up to scratch?
Do you clearly see your bright corners from the chair?

I would be very unhappy if I could. I literally cannot see any on mine even after a couple minutes in full darkness.

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post #8250 of 13257 Old 08-25-2018, 03:51 PM
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Originally Posted by christoffeldg View Post
It's nice to hear some critical thought about JVC. Sometimes I feel many on this forum discard the flaws the JVCs tend to exhibit and fail to mention them/minimize their effect, with lots of disillusioned people getting back claiming their eshift was a lot less sharp than expected, their eshift unit made a lot more noise than expected, etc. While at the same time piling dirt on the Sony's to such an extent that people feel the need to become defensive.

Here's hoping we can become a little less biased when the new units roll around, and look at these machines more at face value.
I dont think thats how it works exactly.

I have multiple posts in this thread piling truckloads of dirt on the units I recived in a no hold barred manner. Not sugar coating a thing. I am prepared to talk at length about problems if there are any. I have repeatedly mentioned lens reflections which is the biggest issue for me.

If anybody in a Sony thread mentions a problem inherent with the design, you have the likes of Roxiedog and co jumping on them saying 'well Sony has sold xx units and they are the best blah blah blah, this is the owners thread, get lost'.

Sony is infalible on this forum. And the only reason why is it has native 4k panels. Honestly most of this 'bias' comes from the other camp.

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