Official JVC RS25/HD950 Owners Thread! - Page 6 - AVS Forum
Forum Jump: 
Reply
 
Thread Tools
post #151 of 1011 Old 10-29-2009, 01:36 AM
AVS Special Member
 
JonStatt's Avatar
 
Join Date: Aug 2001
Location: London, UK
Posts: 2,237
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 16 Post(s)
Liked: 42
From what I can see, the "tweaked" THX setting is no possible with the 550/950/990. I may be missing something.

Go to THX mode, enter service menu. You are then supposed to be able to choose another colour temperature (other than 6500). But this option is now greyed out in the service menu as well and I can't see a way to change it.
JonStatt is online now  
Sponsored Links
Advertisement
 
post #152 of 1011 Old 10-29-2009, 01:44 AM
AVS Special Member
 
clehner's Avatar
 
Join Date: Feb 2000
Location: Berlin, Germany
Posts: 1,214
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by JonStatt View Post

But this option is now greyed out in the service menu as well and I can't see a way to change it.


Well, no harm done here. Better do a full CMS calibration including greyscale. I you can measure the greyscale you should normally be able to adjust a setting to REC709, too. The trick you are obiously referring to was only necessary as long as the CMS with the first firmware of the HD750/rs20 did not work properly.

Regards
Christoph
*************
Contact via Public Profile
clehner is offline  
post #153 of 1011 Old 10-29-2009, 02:29 AM
AVS Special Member
 
JonStatt's Avatar
 
Join Date: Aug 2001
Location: London, UK
Posts: 2,237
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 16 Post(s)
Liked: 42
Quote:
Originally Posted by clehner View Post

Well, no harm done here. Better do a full CMS calibration including greyscale. I you can measure the greyscale you should normally be able to adjust a setting to REC709, too. The trick you are obiously referring to was only necessary as long as the CMS with the first firmware of the HD750/rs20 did not work properly.

Okay understood, thank you. I was just experimenting while waiting for my calman Spyder 3 meter to arrive (should come later today or tomorrow). I will do a faull CMS calibration.
JonStatt is online now  
post #154 of 1011 Old 10-29-2009, 08:30 AM
AVS Special Member
 
lovingdvd's Avatar
 
Join Date: Jul 2002
Posts: 8,821
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
Liked: 24
Quote:
Originally Posted by JonStatt View Post

From what I can see, the "tweaked" THX setting is no possible with the 550/950/990. I may be missing something.

Go to THX mode, enter service menu. You are then supposed to be able to choose another colour temperature (other than 6500). But this option is now greyed out in the service menu as well and I can't see a way to change it.

Thanks for letting us know. Seems they may have closed that option then. Another option for those so inclined may be to change the 6500 calibration, which I believe can be done in the service menu. So IOW set the 6500 calibration as necessary for D65, then that should effectively do the same thing as the previous tweak.

That being said, I too agree that there are huge advantages to just doing a full CMS, grayscale, and gamma calibration and not using THX. These advantages include a more accurate calibration, control over gamma, and control over the sharpness and detail enhance settings (my favs).
lovingdvd is offline  
post #155 of 1011 Old 10-29-2009, 10:37 AM
AVS Special Member
 
JonStatt's Avatar
 
Join Date: Aug 2001
Location: London, UK
Posts: 2,237
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 16 Post(s)
Liked: 42
Well my "enhanced" spyder3 came today. So I now have the challenge of using Calman for the first time. I am very technical and have calibrated many monitors. But this is my first projector calibration. Is there any guide anywhere to cover aspects such as, do I point the meter towards the screen or the projector? I understand it would be desirable to point it to the screen, but I also read other meters like the eye-one display 2, are not good when pointed to the screen.
JonStatt is online now  
post #156 of 1011 Old 10-29-2009, 12:17 PM
AVS Addicted Member
 
Jason Turk's Avatar
 
Join Date: Oct 2000
Location: Rochester, NY USA
Posts: 12,451
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by JonStatt View Post

Well my "enhanced" spyder3 came today. So I now have the challenge of using Calman for the first time. I am very technical and have calibrated many monitors. But this is my first projector calibration. Is there any guide anywhere to cover aspects such as, do I point the meter towards the screen or the projector? I understand it would be desirable to point it to the screen, but I also read other meters like the eye-one display 2, are not good when pointed to the screen.

Pointing to the screen is best when possible as it will take into consideration the screen itself when measuring. That being said, I don't know if you meter is sensitive enough to do that (never worked with that). A trick if you are having issue is to make the image much smaller (as small as it will go based on your zoom location). Why? Makes the windows you are measuring brighter and thus easier to read.

But basically the RS25 is no different than any other display, other than you have a full CMS. I would recommend doing it in User 1 or 2 and not one of the presets. Takes longer since everything is from scratch, but you'll get better results overall.
Jason Turk is offline  
post #157 of 1011 Old 10-29-2009, 01:16 PM
Senior Member
 
drewski11's Avatar
 
Join Date: Jan 2008
Location: SF Bay Area, CA
Posts: 238
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by JonStatt View Post

Well my "enhanced" spyder3 came today. So I now have the challenge of using Calman for the first time. I am very technical and have calibrated many monitors. But this is my first projector calibration. Is there any guide anywhere to cover aspects such as, do I point the meter towards the screen or the projector? I understand it would be desirable to point it to the screen, but I also read other meters like the eye-one display 2, are not good when pointed to the screen.

you should check out the Calibration sub-forum. probably more DIY'ers vs. here to get tips from
drewski11 is offline  
post #158 of 1011 Old 10-29-2009, 03:25 PM
AVS Special Member
 
JonStatt's Avatar
 
Join Date: Aug 2001
Location: London, UK
Posts: 2,237
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 16 Post(s)
Liked: 42
Quote:
Originally Posted by Jason Turk View Post

Pointing to the screen is best when possible as it will take into consideration the screen itself when measuring. That being said, I don't know if you meter is sensitive enough to do that (never worked with that). A trick if you are having issue is to make the image much smaller (as small as it will go based on your zoom location). Why? Makes the windows you are measuring brighter and thus easier to read.

But basically the RS25 is no different than any other display, other than you have a full CMS. I would recommend doing it in User 1 or 2 and not one of the presets. Takes longer since everything is from scratch, but you'll get better results overall.

Thanks Jason. After your reply, I thought I should check with Spectracal themselves as they will have tried the Spyder3 with many configurations. They believe the Spyder3 will work fine pointing towards the screen.
JonStatt is online now  
post #159 of 1011 Old 10-29-2009, 05:21 PM
AVS Addicted Member
 
Jason Turk's Avatar
 
Join Date: Oct 2000
Location: Rochester, NY USA
Posts: 12,451
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Well there you go. I'd trust what they say as they test about all the probes (from the inexpensive to the mega-buck stuff).
Jason Turk is offline  
post #160 of 1011 Old 10-29-2009, 09:04 PM
AVS Special Member
 
lovingdvd's Avatar
 
Join Date: Jul 2002
Posts: 8,821
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
Liked: 24
Quote:
Originally Posted by JonStatt View Post

Thanks Jason. After your reply, I thought I should check with Spectracal themselves as they will have tried the Spyder3 with many configurations. They believe the Spyder3 will work fine pointing towards the screen.

Does your spyder come with a diffuser?

Glad to hear your got direction from them on this because I would think that their calibration tables may be based on one type of approach over the other (screen vs. direct into the pj). I have always gotten the best results by training my spyder 2 to my EyeOne Pro and then using the Spyder2 diffuser pointing it directly into the lens from about 20". The key benefit here is that it enables me to read consistently down very low, such as 5% and lower even. This is important to gamma calibration as well as getting 5% level correct in grayscale, and for getting accurate on/off CR readings.
lovingdvd is offline  
post #161 of 1011 Old 11-04-2009, 02:13 PM
AVS Addicted Member
 
R Harkness's Avatar
 
Join Date: May 2001
Location: Toronto, Ontario, Canada
Posts: 11,964
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 92 Post(s)
Liked: 319
Help please!

I've got a major issue that I have to figure out here.

Tonight I'm finally able to check out my RS20 on my screen (it's been in the box during my reno since spring!). Here is the issue I'm encountering:

My set up uses a big screen and 4 way automated masking. I'm using a "zooming" method to vary the image size, then re-mask.

I knew that along with zooming and re-focusing. Since the projector will be above screen center, it will always have some degree of vertical lens shift. This means when I zoom out I expect the top/bottom to not zoom out equally. So I've expected to have to use some vertical lens shifting as I zoom to fit the screen.

However, I wanted to ensure that I don't have to do horizontal (side to side) lens shifting. I want the horizontal lens shift to be perfectly centered so that when I zoom out the sides of the image zoom evenly. Therefore I wanted to ensure my projector was ultimately placed with it's lens directly in the horizontal center of the screen, not off to one side at all. So with the lens shift centered, it should zoom out evenly on each side.

So...I had the screen wall re-built flat, the screen precisely set up the same distance between the side walls. My architect and his assistant measured to get a mark on the floor (where the projector is going) dead center to the center of the screen. So that is where my projector lens has ended up.

Then I wanted to ensure that the lens shift itself was perfectly centered.
Since, annoyingly, JVC does not put any "0" point or increments on the lens control, you don't know for sure it's centered. The only way I figured I could try to ensure it is centered was to project an image against the wall (lens pattern, actually), shift it all the way to the left side, make a mark, shift it all the way to the right side, make a mark, and then since that describes the full distance from full lens shift left to full lens shift right, I made a mark in the middle of those L/R marks. Then I centered the lens shift so the center of the image is at that center mark.

I figured now I have the lens shift centered.

So then I put the projector in it's spot, lens placed at the mark that should have the lens in the center of the screen (I just re-checked it and that mark does seem to match screen center). I fire up the projector and the image is NOT horizontally centered on the screen!


I can't figure out why the heck it isn't.

It's fairly well to the right side of the screen. Almost 1/4 to 1/3 more to the right side than the left.

So I'm going crazy here. Was my method for setting the horizontal lens shift to the center a sound method or not? Any suggestions on this situation?

Many thanks.

Rich H

(BTW, today we spent a lot of time ensuring the projector lift/shelf was aligned with the plane of the screen. I lined the projector up with that shelf so it shouldn't be the case that the projector is off-kilter in terms of aiming squarely at the screen. So far the only culprit I can figure to point at is the lens shift). ALSO: For some reason not only is the lens not centered, but the image is also uneven, one side lower than the other. I can't figure out how this would be so, given I had the screen placed "plum" so it is level, and we did the same with the projector lift today (put a level on it and it's plum). All the feet of the projector are screwed all the way in, so
it's not that some of the feet are higher than the other. I just can't friggin' figure out where all of this is going wrong....)
R Harkness is online now  
post #162 of 1011 Old 11-04-2009, 02:34 PM
Senior Member
 
drewski11's Avatar
 
Join Date: Jan 2008
Location: SF Bay Area, CA
Posts: 238
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Rich -

Where was the projector when you were making the Full Right and Full Left marks? It sounds like it was not on the shelf where it is mounted now? Is it possible that it was not aligned square to the screen for that measurement?

In any case, if the top and bottom of the projected image are parallel to the top/bottom of the masking with no visible keystoning (can measure right and left image height to verify they are equal) then the projector should be set square to the screen.

It sounds like you went to great lengths to ensure that the lens was positioned at the mid-point of the screen so I would just recenter the image with the horizontal lens shift, and then try zooming. If the image stays centered, then you're good to go. If not, then fire the architect and assistant who marked the center point for the projector
drewski11 is offline  
post #163 of 1011 Old 11-04-2009, 03:13 PM
AVS Addicted Member
 
R Harkness's Avatar
 
Join Date: May 2001
Location: Toronto, Ontario, Canada
Posts: 11,964
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 92 Post(s)
Liked: 319
Thanks drewski11,

But this is just staying bizarre.

First weird thing is how the image is tilted down on one side. I just used a level (with a bubble) and checked the screen. It is level. I even measured, and then checked with a level the top/bottom (Carada Masquerade) screen masks, just in case they weren't level to the screen. But they measured level. I measured the shelf the projector is sitting on. It is perfectly level. I made sure all the feet of the projector are screwed fully in, so it should be level. EVERYTHING would seem to be levelled, and yet the image from the projector is tilted!

Then there's the horizontal lens shift issue. It just doesn't seem to be zooming out equally on the sides. This was the case both using my "pre-centered" lens shift, and then I instead tried shifting the lens shift to get the image centered on my actual screen. It's still zooming out unequally so I have to use horizontal lens shift to adjust the image - just what I didn't want. Not only that I'm SURE during my tests months ago that if I centered the image it zoomed out equally on all sides.

I just don't know what the h#ll is going on. Is it possibly the case that some projector's lens or optics aren't level or something, such that even if the projector is on a level surface the image can still be skewed?

But...all of this may be moot as my vertical lens shift seems to have stopped working . (ETA: Hmm...maybe it's just finicky. Possibly it doesn't work when the image is at the far left of the horizontal image shift position. When I centered the lens it seemed to work again).

I just tried re-centering the lens controls again, this time on my actual screen, shifting the image all the way to the left then all the way to the right, marking those points, then shifting the image so it measures directly between them. This still leaves the image way over to the left side of my screen with my projector lens supposedly centered to the screen. What the h#ll?
R Harkness is online now  
post #164 of 1011 Old 11-04-2009, 03:56 PM
 
themasterlord's Avatar
 
Join Date: Oct 2009
Posts: 4
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
very cool!!!
themasterlord is offline  
post #165 of 1011 Old 11-04-2009, 04:12 PM
AVS Addicted Member
 
R Harkness's Avatar
 
Join Date: May 2001
Location: Toronto, Ontario, Canada
Posts: 11,964
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 92 Post(s)
Liked: 319
R Harkness is online now  
post #166 of 1011 Old 11-04-2009, 04:32 PM
AVS Addicted Member
 
darinp2's Avatar
 
Join Date: Sep 2003
Location: Seattle, WA
Posts: 21,165
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 43
Quote:
Originally Posted by R Harkness View Post

Then there's the horizontal lens shift issue. It just doesn't seem to be zooming out equally on the sides.

I'm not sure if I'm understanding completely, but I'm going to give something a shot just in case it helps. It seems that if you set the horizontal lens shift to the left side and twist the projector until the image is centered, then when you zoom in and out the sides will zoom unequally. Now if you put the horizontal lens shift to the right side and twist the projector until the image is centered and do the same thing with zooming in and out, will the sides zoom unequally, but in the opposite way as before? If so, then it seems like the way to actually find the perfect position for the horizontal lens shift would be to just try different settings between to the left and to the right until you find the one where the sides zoom the most equally. Of course you might have issues with the sides being different heights at that position, but you would just have to find that position and see.

If I'm wrong about my assumption above that starting with the horizontal lens shift to the left will give the opposite results as far as the inequality while zooming compared to have the horizontal lens shift at the right then going to the center doesn't seem like it was likely to solve the problem anyway.

--Darin

This is the AV Science Forum. Please don't be gullible and please do remember the saying, "Fool me once, shame on you. Fool me twice, shame on me."
darinp2 is offline  
post #167 of 1011 Old 11-04-2009, 04:47 PM
AVS Addicted Member
 
R Harkness's Avatar
 
Join Date: May 2001
Location: Toronto, Ontario, Canada
Posts: 11,964
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 92 Post(s)
Liked: 319
Thanks for the input Darin.

Yes, the idea as I understand it is IF you shift the lens fully to one side when you zoom the sides will not zoom out evenly. If you want the image to zoom out evenly you should have no lens shift, so the lens shift mechanism centered. As I mentioned, it seemed to me the logical way to find the lens shift center was to shift all the way to the left, mark that as the furthest-left-lens-shift, do the same with the right, and then I have marked the furthest left and right lens shift points. Then it follows that, marking the half-way point between those points would be the lens-centered point. Which is what I did and I centered the lens that way, using that halfway point to line up with the center of my image.

Doing so does seem to help get the image zooming out more evenly - not perfectly but better. But it still doesn't make sense that with the lens shift mechanism supposedly centered, and the projector lens perfectly centered with my screen center, that the image isn't centered and is instead still projecting off to the left side.
(I'm also getting significantly more fringing, in terms of lack of convergence, than I got when I tested my projector at Mr.littlejeans' house, for some reason).
R Harkness is online now  
post #168 of 1011 Old 11-04-2009, 06:24 PM
703
Member
 
703's Avatar
 
Join Date: Mar 2006
Location: New Zealand
Posts: 167
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by R Harkness View Post

Thanks drewski11,

But...all of this may be moot as my vertical lens shift seems to have stopped working . (ETA: Hmm...maybe it's just finicky. Possibly it doesn't work when the image is at the far left of the horizontal image shift position. When I centered the lens it seemed to work again).

This is a problem or feature of all RS10/20's. Extreme angles will freeze up the shifting. Takes some mucking around with the controls to get it moving again.

Founder | BullsEye Calibration | www.bullseyecal.co.nz
703 is offline  
post #169 of 1011 Old 11-04-2009, 06:38 PM
 
themasterlord's Avatar
 
Join Date: Oct 2009
Posts: 4
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
very nice tv!
themasterlord is offline  
post #170 of 1011 Old 11-04-2009, 06:43 PM
AVS Club Gold
 
mrlittlejeans's Avatar
 
Join Date: Jan 2004
Location: Memphis
Posts: 4,718
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Liked: 192
Is the pj throwing a perfect rectangle on the screen? If not, the pj isn't square with the screen somewhere. This is one of the most difficult things for me to get right and I get really picky about this at home. If not, even if the lens shift is in the perfect center, you won't zoom out equally. I've also found that leveling a projector can be difficult as well as only a slight bit out that you wouldn't even notice over the length of the level can grow significant over the length of a 10' wide screen. Its good to use a level and measurements to get everything in rough position but then hand tune to the ultimate alignment based on filling the screen correctly.

Absence of evidence is not evidence of absence

mrlittlejeans is offline  
post #171 of 1011 Old 11-04-2009, 07:33 PM
AVS Special Member
 
erkq's Avatar
 
Join Date: Sep 2006
Posts: 5,523
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 8 Post(s)
Liked: 95
Quote:
Originally Posted by themasterlord View Post

very nice tv!

erkq is offline  
post #172 of 1011 Old 11-04-2009, 11:06 PM
AVS Club Gold
 
GlenC's Avatar
 
Join Date: Jun 2003
Location: Los Angeles - Whittier, CA
Posts: 2,555
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by R Harkness View Post

Thanks drewski11,

But this is just staying bizarre.

First weird thing is how the image is tilted down on one side. I just used a level (with a bubble) and checked the screen. It is level. I even measured, and then checked with a level the top/bottom (Carada Masquerade) screen masks, just in case they weren't level to the screen. But they measured level. I measured the shelf the projector is sitting on. It is perfectly level. I made sure all the feet of the projector are screwed fully in, so it should be level. EVERYTHING would seem to be levelled, and yet the image from the projector is tilted!

Then there's the horizontal lens shift issue. It just doesn't seem to be zooming out equally on the sides. This was the case both using my "pre-centered" lens shift, and then I instead tried shifting the lens shift to get the image centered on my actual screen. It's still zooming out unequally so I have to use horizontal lens shift to adjust the image - just what I didn't want. Not only that I'm SURE during my tests months ago that if I centered the image it zoomed out equally on all sides.

I just don't know what the h#ll is going on. Is it possibly the case that some projector's lens or optics aren't level or something, such that even if the projector is on a level surface the image can still be skewed?

But...all of this may be moot as my vertical lens shift seems to have stopped working . (ETA: Hmm...maybe it's just finicky. Possibly it doesn't work when the image is at the far left of the horizontal image shift position. When I centered the lens it seemed to work again).

I just tried re-centering the lens controls again, this time on my actual screen, shifting the image all the way to the left then all the way to the right, marking those points, then shifting the image so it measures directly between them. This still leaves the image way over to the left side of my screen with my projector lens supposedly centered to the screen. What the h#ll?

Rich,

It sounds like the projector is not properly aimed at the screen. If the image is parallel at the top but angles/dips down (say on the left), then the projector is pointed to the left and tilted slightly counter clockwise....

The overall image is always larger on the side the projector is pointed. When truly aimed perpendicular to the screen, the left and right image height measurement will be equal. Accordingly, if the image is wider at the bottom than the top, the projector is pointed down from perpendicular.....

Glen Carter
Home Theater Calibration
www.ISFHT.com
GlenC is offline  
post #173 of 1011 Old 11-05-2009, 02:10 AM
AVS Special Member
 
Manni01's Avatar
 
Join Date: Sep 2008
Posts: 2,236
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 57 Post(s)
Liked: 105
Quote:
Originally Posted by R Harkness View Post

Thanks drewski11,

But this is just staying bizarre.

First weird thing is how the image is tilted down on one side. I just used a level (with a bubble) and checked the screen. It is level. I even measured, and then checked with a level the top/bottom (Carada Masquerade) screen masks, just in case they weren't level to the screen. But they measured level. I measured the shelf the projector is sitting on. It is perfectly level. I made sure all the feet of the projector are screwed fully in, so it should be level. EVERYTHING would seem to be levelled, and yet the image from the projector is tilted!

Then there's the horizontal lens shift issue. It just doesn't seem to be zooming out equally on the sides. This was the case both using my "pre-centered" lens shift, and then I instead tried shifting the lens shift to get the image centered on my actual screen. It's still zooming out unequally so I have to use horizontal lens shift to adjust the image - just what I didn't want. Not only that I'm SURE during my tests months ago that if I centered the image it zoomed out equally on all sides.

I just don't know what the h#ll is going on. Is it possibly the case that some projector's lens or optics aren't level or something, such that even if the projector is on a level surface the image can still be skewed?

But...all of this may be moot as my vertical lens shift seems to have stopped working . (ETA: Hmm...maybe it's just finicky. Possibly it doesn't work when the image is at the far left of the horizontal image shift position. When I centered the lens it seemed to work again).

I just tried re-centering the lens controls again, this time on my actual screen, shifting the image all the way to the left then all the way to the right, marking those points, then shifting the image so it measures directly between them. This still leaves the image way over to the left side of my screen with my projector lens supposedly centered to the screen. What the h#ll?

High Rich,

Just my .2 cents:

1) Don't trust the levels. As it has been said, it's only a rough indication, you should still adjust carefully the feet and the horizontal angle (not shift) of the PJ until you get a prefect rectangle on the screen.

2) Make sure you centre the picture vertically (with the lens shift this time) before you measure the range of the horizontal lens shift. When the picture is shifted up or down, it limits the range of the horizontal shift, and vice versa (as you have noticed). If your vertical shift is not centered, it will affect your measurement on the horizontal shift. So center both (roughly) before you try to measure the range of one, and center again before measuring/centering the other.

3) Also check that you don't have any keystone correction!

Edit: just to clarify, I would suggest you center the lens shift both vertically and horizontally (roughly), measure the range of the shift for both (with the other centered), center both precisely, then zoom the picture to your screen's physical width, center your PJ physically to your screen without using the lens shift - only by adjusting the feet and moving the body of the PJ horizontally on the shelf - until you get a perfect rectangle (it won't be vertically adjusted to your screen yet, concentrate on the horizontal placement and the geometry of the picture), then double check the horizontal range and center it (fine-tuning physical position if necessary), and finally use the vertical lens shift to center the screen vertically. Hopefully your horizontal geometry will not be affected when you zoom.

Good luck!
Manni01 is online now  
post #174 of 1011 Old 11-05-2009, 04:42 AM
AVS Special Member
 
Lawguy's Avatar
 
Join Date: Sep 2004
Posts: 5,706
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked: 11
I have spent many hours attempting to get an image that is perfectly square and centered to the screen. It requires a lot of patience.

I agree with the other who think that your projector is not perfectly perpendicular to the screen. I say this because of the two major symptoms that you describe: (1) the image is not perfectly square and (2) the image is not centered.

I have not gone to the lengths that you have in ensuring that my setup conditions are ideal so I assumed that some of my troubles were caused by slight wall bowing or other things. Perhaps not.

I would do the following. First, get the image centered on the screen from what you measure to be the ideal centered location. This will require you to pivot the projector horizontally on an axis. Keep the projector in its centered location and just rotate it until it is centered. The image from this centered position will likely not be at all squared to the screen. Next, try to get the image square. My projector is shelf mounted so this involves a lot of tedious playing with the projector's feet to get things perfect. I also keep some things around to use as shims for the feet. CDs work well and are easy to put in and remove. I use the shims to test out how an adjustment will affect the image. Hopefully, at the end of this process you will have an image that is centered and square to the screen.

Affable Nitwit
Lawguy is offline  
post #175 of 1011 Old 11-05-2009, 06:54 AM
AVS Addicted Member
 
Jason Turk's Avatar
 
Join Date: Oct 2000
Location: Rochester, NY USA
Posts: 12,451
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
There is a simple installers trick...if you imagine looking down from the ceiling onto the room, the left edge of the screen, right edge of the screen, and lens center form a triangle. If you down divide that triangle down the middle (lens to screen center) you have 2 equal right triangles. The line between the lens and each side is the hypoteneus of each one. Being that they are equal right triangles, those said hypoteneus' are equal (or should be). So, if you take a string from the lens center to the left side and mark it, if you now move the string to the exact other side of the screen, it should be in the exact same position as what you just marked. If it is not, then your projector is not centered on the screen and that would in part explain the issue you are having.
Jason Turk is offline  
post #176 of 1011 Old 11-05-2009, 07:35 AM
AVS Special Member
 
Jive Turkey's Avatar
 
Join Date: Jun 2002
Location: good old USA
Posts: 1,461
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Liked: 15
I swore I had an upper rising right corner; even sent my Black Pearl into Sony service for a check. Sony found everything to be in order, and turned my projector around to me pretty quickly. Good service, Sony.

Glen and Jason helped me on this a few months ago. It did come down to a positioning issue and took a lot of fiddle-farting around to get everything right. I took it off a ceiling mount and went to stand mount at about a foot low of screen center, so I would have maximum positioning flexibility and minimum lens shift. At the end of the day, I still end up with a 1/4" bow at the top and bottom center of the image, which is probably due to the wall the screen is mounted on. I'm the only one who would ever notice it, but I created a DIY masking setup (see the DIY screen forum) that takes care of that anytime I have other than a full 16x9 aspect ratio.

It can be a task to get everything positioned just so. I don't even want to move it to replace the lamp when it starts to fade, but of course I will.

See ya. Dave

"High Fidelity audio has been like a dog chasing his tail. High Fidelity in my marriage has been much more rewarding cause she knows where I sleep."
Jive Turkey is online now  
post #177 of 1011 Old 11-05-2009, 09:25 AM
AVS Special Member
 
erkq's Avatar
 
Join Date: Sep 2006
Posts: 5,523
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 8 Post(s)
Liked: 95
Quote:
Originally Posted by Jason Turk View Post

There is a simple installers trick...if you imagine looking down from the ceiling onto the room, the left edge of the screen, right edge of the screen, and lens center form a triangle. If you down divide that triangle down the middle (lens to screen center) you have 2 equal right triangles. The line between the lens and each side is the hypoteneus of each one. Being that they are equal right triangles, those said hypoteneus' are equal (or should be). So, if you take a string from the lens center to the left side and mark it, if you now move the string to the exact other side of the screen, it should be in the exact same position as what you just marked. If it is not, then your projector is not centered on the screen and that would in part explain the issue you are having.

Then from there, adjust the projector's yaw and pitch angles until you get a rectangle instead of a trapezoid. You'll probably have to use lens shift as you work. As said previously, aim the entire projector case away from the side that's too big. Do the same with the top and bottom. If the projector case is not perfectly lined up with the screen, who cares? It's the optics that are important and getting rid of the trapezoid effect ensures the optics are lined up properly.
erkq is offline  
post #178 of 1011 Old 11-05-2009, 10:20 AM
AVS Club Gold
 
mrlittlejeans's Avatar
 
Join Date: Jan 2004
Location: Memphis
Posts: 4,718
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Liked: 192
Quote:
Originally Posted by Jason Turk View Post

There is a simple installers trick...if you imagine looking down from the ceiling onto the room, the left edge of the screen, right edge of the screen, and lens center form a triangle. If you down divide that triangle down the middle (lens to screen center) you have 2 equal right triangles. The line between the lens and each side is the hypoteneus of each one. Being that they are equal right triangles, those said hypoteneus' are equal (or should be). So, if you take a string from the lens center to the left side and mark it, if you now move the string to the exact other side of the screen, it should be in the exact same position as what you just marked. If it is not, then your projector is not centered on the screen and that would in part explain the issue you are having.

I'd like to add that I have had a hard time in the past finding string that didn't stretch. Anyone have any suggestions? You have to pull it tight but it cannot have any stretch or the exercise is rendered pointless.

Absence of evidence is not evidence of absence

mrlittlejeans is offline  
post #179 of 1011 Old 11-05-2009, 10:27 AM
AVS Special Member
 
erkq's Avatar
 
Join Date: Sep 2006
Posts: 5,523
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 8 Post(s)
Liked: 95
Quote:
Originally Posted by mrlittlejeans View Post

I'd like to add that I have had a hard time in the past finding string that didn't stretch. Anyone have any suggestions? You have to pull it tight but it cannot have any stretch or the exercise is rendered pointless.

Get a roll of nylon weed-wacker string.
erkq is offline  
post #180 of 1011 Old 11-05-2009, 10:28 AM
AVS Addicted Member
 
R Harkness's Avatar
 
Join Date: May 2001
Location: Toronto, Ontario, Canada
Posts: 11,964
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 92 Post(s)
Liked: 319
Thank you everyone for the very detailed replies!

My architect/his assistant and I had used the string/tape measurer method and triangulation (as suggested by Jason) to arrive at both the horizontal center of the screen and trying to get the plane of the projector shelf in line with that of the screen. I feel pretty confident the projector is properly positioned with it's lens in the center of the screen. So I still have to figure out how the image ends up well to one side of the screen.

I'll have to check if the projector is perpendicular with the screen plane. I'm sure it's not perfect, but it's hard for me to imagine it could be so off as to send the image way off to one side. I would think this would mean the projector is pretty skewed, which would mean that one side of the rectangle ought to be quite visibly taller than the other.

But checking the projector again just now, lining up the 2:35:1 area of the lens shift pattern with my masking (which measures very even) it seems to me I'm getting an even looking rectangle from the projector. So it doesn't appear to be a distorted rectangle with one side larger. Rather, it just looks like it's not level, one side of the image tilted up somewhat.

So it seems that despite the fact the screen measures level and the projector shelf measures level, I'll still have to adjust the projector feet to get the image level.

But, this implies to me that my issue isn't that the projector is significantly skewed with the plane of the screen. I'll look closer, but still have to figure out why the image ends up to one side.
R Harkness is online now  
Reply Digital Hi-End Projectors - $3,000+ USD MSRP

Tags
Jvc , Vivitek D950hd 3000 Lumen 1080p Office And Home Theater Projector
Gear in this thread - D950hd by PriceGrabber.com

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off