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Scheimpflug messed up focus?

post #1 of 25
Thread Starter 
I finally managed to get my Cine8 on the ceiling and started the setup. Went by the (Barco) book. Optical lens focusing, raster centering, RB horizontal alignment on G. All went well. Then came Scheimpflug adjustment. Focus variation was not much, but decided to do the whole thing. Staring with G I saw that focus became more slightly uniformly off, but the manual said I would need to redo optical lens focusing afterwards so did not worry much. Now focus is all screwed up and I cannot get it back. Unfortunately Scheimpflug is done with a stepless screw on either side of each lens's top side. I have tried undoing the Scheimpflug adjustment (in essence blindly) but to no avail. Focus is totally off. Can barely read the menus...
post #2 of 25
Thread Starter 
Maybe it's just my mind playing games but it looks like it occasionally focuses better (like a camera trying to autofocus). Could it be I have messed something up behind the lenses adjusting the Scheimpflug screws?
post #3 of 25
Thread Starter 
No, it's not my mind playing games. I started up the pj just now after having left it alone for a few hours and the warm-up message was almost focused. I noticed a couple of fingertips on the green lens, wiped them clean and the focus was off again. Turned off, turned back on after a few minutes, focus was considerably -but not horrifically- off. It Now it's warming up and it appears (but again it could be my mind) that it gets worse as it warms up. Is it possible I have broken/unstuck something with the Scheimpflug screws or that warmed up something changes?
post #4 of 25
Thread Starter 
It definitely got worse warming up. Through the warm-up period (20 min) there was a marked deterioration of focus. In view of the latest events, however, it might have been just the progress of the "disease", even though this morning it started off better than IIeft it last night. Close to the end of the 20 min warm-up it appeared as if the image slightly zoomed in and out (maybe what I have already described as the image trying to autofocus, Then came the end of the warm-up (or just the end): all 3 tubes went out (same way thay do at the end of the warm-up for a second until the pj locks on the input). Only this time they never came back on. Tried changing the source, nothing (not even the "source not available" message. Shut down, back on after after a few minutes, nothing. Shut down, flipped electrical panel switch for both the pj and the hdfury, made coffee for my wife's friends, turned everything back on. This time everything came on, but pj out of focus...
post #5 of 25
If you could post photos of the focus problem, it would help the experts here with diagnosing.
post #6 of 25
Thread Starter 
Here follow some photos. This time round the guns shut down shortly after the warm-up period completed, hence the lack of photos from a setup attempt. It warmed up with the focus going down the drain as time passed (as you may see starting from poor and ending up a completely illegible blur). Being too worried I might cause more damage than has already occurred, I did not turn back on to shoot more pics. If it would be safe to turn back on and let it run until (if) I can project the focusing crosshatch, let me know. Meanwhile, I'll describe best as I can. Entering Installation menu, starting optical focusing, green tube cross hatch: lines appear about 2/3" wide and out of focus [normally I would guess 1/4" with distinctly visible small lines stacking up to make up the long lines (like elongated pixels)]. So the lines and dots of the pattern were much thicker than normal and their "texture" was no longer visible (even with my nose right up the screen). In view of this shutting down behavior I am inclined to think that some kind of overcurrent/overheat protection kicks in. Maybe the guns were (are) drawing more current than they should, and this leads to "overshooting" the phosphor (hence the thicker lines) and when this goes over a certain point a protection circuits kicks in. Or, while messing with the Scheimpflug screws, I may have deformed something on the tube/lens assembly making it impossible to focus the electron beam on the phosphor (I would venture to guess the lens focusing still works, but the phosphor exitation is blurred). I obviously have a very superficial understanding of the "mechanics" involved in the operation of the pj...

At warm-up start


Some time into the warm-up


After warm-up complete (if I remember correctly with the Adjust menu, but it is totally illegible)


The insides are very clean (certainly much cleaner than I was expecting after more than 10 years)


While opening the rear internal cover this screw rolled onto the floor. Looks similar to the ones holding things on the rear bulkhead on the other side of the expansion cards.
post #7 of 25
I am sure Curt Palme will have your answer.
post #8 of 25
1) Don't use the warmup screen, it puts unneccessary wear on the tubes.

2) You have two focusing issues to deal with: Optical and electronic. You first need to know where the problem is. If the tube face itself is out of focus, then you have an electronic issue within the focus circuits, and no amount of mechanical adjustments will fix that. You need the tube face in focus first. To do that, set the contrast to 100%, and put on sunglasses and look into the lenses. Focus the tube face reasonably well, you'll fine tune this once the mechanical is done, but at least verify that everything is readable on each tube face all over each tube face.

3) I don't see why the Scheimpflug adjustment is that hard, the Barco is about as easy as it gets. You're right, the screws are not stepped, and are multiturn. You're physically adjusting the lens position with regards to the tube face. One Scheimpflug adjusts the bottom right and top left, the other does top right and bottom left.
Use the lens focus to adjust the centre focus first, no matter how bad the SCheimpflug is misadjusted, you will get the centre focus set OK so that you can read it. Once that's done, then use an 8mm socket to turn the Scheimpflug screws. Once in a blue moon, one will strip, but that's very rare, and you really need to force the bolt to strip it. I'm assuming that's not the case.
I think the screws are about 10 turns or so. You can always set them manually to about 5 turns so they are close to the middle of the adjustment. That should be relatively close. Again, have the contrast at 100%, and focus the corner adjustments. Once the Scheimpflug is set, then redo the electronic focus and astig, and then go back and do the Scheimpflug again.
post #9 of 25
Thread Starter 
Hi Curt, thanks for the answers. Before I ask my questions let me point out that the problem has evolved in the guns shutting down by themselves. PJ stays on, fans working, but crt's are off. I had noticed a change in the sound the pj was making as soon as it went into the service menus and back to normal when back out just showing the source (it sounded as if something started working harder - at first I thought it was a change in the fan noise as if one fan was not rotating on its bearings right but stressed, but it's probably sthng else around the rear of the pj). Now, the guns shut down almost immediately after I go into the menus (at least that's when they went out last time and I am a bit worried about experimenting too much). So before I can solve anything ralated to focus I would need to keep the guns firing.

Also, please, note that focus markedly deteriorates as the pj warms up.

Maybe not important, but while centering I could not see at the same time the right and left edges of the raster (same in all 3 tubes). Projector distance was set correctly (although it does not allow me to change height difference from top of screen and the 1.5" it gives me are not the case)
Quote:
Originally Posted by Curt Palme View Post

1) Don't use the warmup screen, it puts unneccessary wear on the tubes.

2) You have two focusing issues to deal with: Optical and electronic. You first need to know where the problem is. If the tube face itself is out of focus, then you have an electronic issue within the focus circuits, and no amount of mechanical adjustments will fix that. You need the tube face in focus first. To do that, set the contrast to 100%, and put on sunglasses and look into the lenses. Focus the tube face reasonably well, you'll fine tune this once the mechanical is done, but at least verify that everything is readable on each tube face all over each tube face.

How do I focus the tube face ?

Quote:
Originally Posted by Curt Palme View Post

3) I don't see why the Scheimpflug adjustment is that hard, the Barco is about as easy as it gets. You're right, the screws are not stepped, and are multiturn. You're physically adjusting the lens position with regards to the tube face. One Scheimpflug adjusts the bottom right and top left, the other does top right and bottom left.
Use the lens focus to adjust the centre focus first, no matter how bad the SCheimpflug is misadjusted, you will get the centre focus set OK so that you can read it. Once that's done, then use an 8mm socket to turn the Scheimpflug screws. Once in a blue moon, one will strip, but that's very rare, and you really need to force the bolt to strip it. I'm assuming that's not the case.

I think the screws are about 10 turns or so. You can always set them manually to about 5 turns so they are close to the middle of the adjustment. That should be relatively close. Again, have the contrast at 100%, and focus the corner adjustments. Once the Scheimpflug is set, then redo the electronic focus and astig, and then go back and do the Scheimpflug again.

The screws are not stripped, but I was worried I might have deformed a mount or sthng. It is not that the Scheimpglug is hard, it is just that having done everything smoothly until then (optical lens focusing, raster centering, CRT projection angle adjustment (horizontal - rectangles with cross), I started on the Scheimpflug, and that totally screwed up all previous adjustments (of course it might have been that the Scheimpflug just temporally coincided with the real cause of this mess). And now for one because of total lack of focus for another because of the lamps going out, I cannot even attempt to do anything. Before the lamp shutdown thing started I tried focusing again (going back to step 1 - optical lens focusing, but there was no way to do it: crosshatch lines and dots were much thicker than normal, their texture was totally invisible, and were out of focus at best).
Edited by georg - 1/21/13 at 3:28pm
post #10 of 25
I'll bet your HV is off. You may have a bad EHT board, HV splitter or HV quadrupler. Check the red light on the EHT board to see if the set goes into HV protect mode when the image disappears.
post #11 of 25
Thread Starter 
Quote:
Originally Posted by Curt Palme View Post

I'll bet your HV is off. You may have a bad EHT board, HV splitter or HV quadrupler. Check the red light on the EHT board to see if the set goes into HV protect mode when the image disappears.

Besides the crt shut-down, would that also explain why I could not get optical lens focusing even close, even before the first shut-down (right after the Scheimpflug attempt)?
post #12 of 25
Yes, if your HV is off, the tube faces will not focus, no matter at what point the electronic focusing is at in the menus.
post #13 of 25
Thread Starter 
Turned the pj back on, left in warm-up for a few minutes to retake some pics (not much more to show, focus becomes worse as it warms up), then "Esc" and had it show my desktop, scenes from a few movies with xbmc. Nothing. It would just not go off. Retried the setup steps, same thing. Impossible to focus.

However, I can be more specific about one thing I mentioned: the change in the noise pitch. It looks like it sounds normal when displaying a full white picture or close to that and changes to a more stressed sound when the picture is darker. Tried several times back and forth amongst others with a setup DVD and it is noisy when displaying a white on black crosshatch, normal (quiet) when displaying a fill white image. Same thing with a normal movie: fluctuates depending on the brightness of the scenes. Same w/ W7: desktop intermediate - noise follows, MS Word opened new empty document (practically white screen) - goes quiet.

All green lights on, the red LED off.
post #14 of 25
Definitely HV issues. Quadrupler, splitter or EHT board. Without swapping them into a known good unit, or buying replacement parts, there's no way to test them.
post #15 of 25
Thread Starter 
In a previous post you said sthng about focusing the tube face. Is this sthng I should try before starting with the boards? If so, how do I go about it? I seem to remember we adjust coils w/ a plastic screwdriver? Where?

If not, I remember you are clearing Barco boards? Right? Do you have mine?
Edited by georg - 1/23/13 at 2:30am
post #16 of 25
Look into the lenses with sunglasses on and see if the tube faces are in focus. If not, go into the focus menu and see if you can adjust them. If not, then your HV is out of range, and you will not get correct focusing. You would need to send me your HV quadrupler and EHT board for me to test.
post #17 of 25
Thread Starter 
Having performed the best optical lens focus I can (Adjustment-Service-Installation-Projector Distance-Optical Lens Focusing), I followed (I think) Curt's advice and did the electromagnetic focusing (Adjustment-Service-Random Access-Selected Source-Focusing). Pushing the adjustment all the way to one end (i.e. 99 on the adjustment scale) gave the best result, which is still not good.

So, from what I can tell the text in Adjustment-Service-Installation appears focused on the crt (looking inside the lenses) and at the same time out of focus on the screen, so that I cannot correct turning the lens barrel (screen photos are the screen projection of the crt photos). Electromagnetic focusing (Adjustment-Random Access-Selected Source-Focusing) improves on focus on the screen, but still not good.

Curt, do these observations shed any light / change your recommendation?

Looking into the green CRT (differences due to handheld camera angle to phosphor)


Looking into the green CRT after Adjustment-Service-Installation-Projector Distance-Optical Lens Focusing-Green


Above image as projected on screen at best focus with lens barrel rotation


Following above, best electromagnetic focus (Adjustment-Service-Random Access-Selected Source-Focusing-Green-Midpoint)


For the record, source is the HD4000 in Ivy Bridge (1080@60p) - HDMI - HDfury3 RGBHV - D15to5BNC - source4. For some reason (before any attempt to readjust the pj after relocation) when HDfury3 was set up to output component, there was a distortion horizontal band just below the middle of the image, so I switched the HDfury3 to RGBHV. While the HDfury3 was outputting component (YPbPr), I tried having the yellow and black BNCs also connected, but I got no image (although my understanding was that in component mode there was no signal in those cables and should function whether left connected or not).
post #18 of 25
Have you moved focus yoke according service manual?

Make best focus (CENTER zone of screen only) by rotating sections of each lenses.
Set value 57 in focus menu in each color.
Move the focus yokes forward or backward until best focus appear on the CENTER of the screen.

p.s. Perhaps the projector is too far respect screen, I see that the raster is too big. If don't place the projector forward you'll have little image in the tube's surface.
post #19 of 25
Thread Starter 
I am back as Arny would -almost- have it!

I found a couple of cards from another nuthead still running a crt who was kind enough to let me try his cards on my pj before sending my cards out for testing and repair/replacement. After back and forth it turns out it was the splitter. In sequence replaced:

G2/focus card
quadrupler
eht
splitter

Having left the "new" quadrupler in and replacing the splitter, the pj shut down the crt's. No LED diagnosis. Replaced the quadrupler with my original one, all OK. Set everything up (had to change overscan settings on the HD4000 to get the whole image in, midpoint electomagnetic focus @ around 15 on average onall crt's, all peripheral settings a little over 50) and a little before being ready to watch a movie after a very long time crt's shut down again (again fans working, all green LEDs on, red LED off). Pj off, back on after a short while, all OK for a bit, then same thing. After a couple of more tries, the crt's go out almost instantly. All the time all LEDs normal.

Sync limitations: only usable outputs were 1920x1080@48p (component 46% horizontal scaling to get all of the image in, otherwise missing about 2/3" on left) and 1920x1080@50p RGBHV. These are produced by the integrated Intel HD4000 fed via a HDfury3 (black). Component output definitely better (slight halo like excessive sharpening visible if using RGBHV option).
Edited by georg - 2/1/13 at 9:54am
post #20 of 25
Thread Starter 
Correction: rear red LED (EHT) on.

Misdiagnosed as we had tried a new (unused) eht. Trying a 3rd one (after my original one and the never used one) worked and the owner let me have it for almost nothing.

Before I go into my first impressions, let me just mention my rude awakening. In fact, 2 of them. All this frustration with exchanging cards, eht's, splitters, the works, and still nothing working, gave me a glimpse of my (our) future. One approach might be to stock up in failure-prone parts (namely the HV section) to prolong the pj's useful life. Which brings us to my rude awakening. OK, if we do that and it is one of these parts that fails we are good to go in a few minutes. What if it is not one of these parts and the failure occurs a year down the road? What if it's a tube? What if it's sthng that in any realistic view is just not worth repairing in a machine with a resale value of next to nothing? Then we are stuck with a dead pj and a few hundred € worth of parts. Sure, we might find someone to buy them at what we had paid, but maybe not. The other part of my ride awakening concerned the pj's replacement. Over a quick search, the digital guys have really serious issues w/ image quality that they "fight" over. One has colors off, the other one beats the heck of all others with black at dark grey levels, another one refreshes half asleep etc. Weren't digital pj's supposed to rid us of the troubles of the large image?...
post #21 of 25
Yup, you pretty much have all the points covered. CRT sets are now typically 15 years old, so some failures are to be expected. Parts like the HV stuff can develop issues by just sitting on the shelf as well, as the parts do age, and the silicone gets weak, causing HV leakage by sitting there. So, stocking up on parts might work for you, or as you've found, may not.

Thing is, CRT still throws a better picture, and overall can be more reliable than a brand new digital in the box. LEt's face it, nothing electronic is an investment. You simply spend money on it to enjoy it. That applies to your computer, digital camera, cell phone, etc as well. So each time a CRT fails, it's a judgement call whether to fix it or not, but ditto on a digital set that needs a $200 bulb. For the most part, the tube condition determines how long a CRT should still be run in a theatre. I haven't seen more failures on most CRTs due to age, my repairs have been pretty consistent, ditto for parts sales over the last 5ish years. Considering that people are pulling out CRTs in favor for digitals in a lot of cases, but also considering that the parts resellers and repair guys have also dropped out of the market is keeping my business consistent.
post #22 of 25
Thread Starter 
My future is here...

Having watched -ecstatic- the renaissance of my Cine 8, a few days and as many movies down the road that darned red LED came back on as the tubes went out. Had just watched Cars 2 w/ my daughter, left playing Avatar for a half hour, and I watched maybe 15 min of Rise of Planet of the Apes. I would say a total of around 2.5 hrs before the crt's shut down again. Turned the pj back on a couple of minutes later, it played OK for 5 minutes or so and out again. I am beginning to think that parts are getting old and past their life expectancy (as Curt mentioned) and am worried that even if I put more parts in, chances are they are the same age and use as mine and, since untestable, they might work for a bit when you try them on a pj, and then give up a few movies down the road.

Anyway, I have so far replaced:

1) the splitter with a new (unused, had never been soldered) one - this fixed the focus issue
2) the quadrupler (not the eht, my mistake) with a used one (had tried a new/unused one that did not solve the problem, then the used one) - this solved the CRT shut-down/red LED problem, until yesterday...

The other guy -who thinks he knows what he's talking about- told me that the EHT either works as it should or not at all, there is no halfway there.

So, Curt, if you still have the stamina, or anyone else:

a) is there sthng not working properly that might be destroying sthng in the HV section after a few hrs/days? Maybe the EHT being off, damaging the quadrupler after so many hrs of operation? Or maybe sthng outside the HV triad, such as a tube?
b) is there sthng that might be causing the CRTs to shut down (EHT red LED on) after some time in operation? I would guess that it might be temperature related maybe? Room is temperature controlled (21°C) and fairly large. All 3 fans working.

Only abnormality (other than shut-down) to report is that there is a change in the pitch of the noise the pj makes sometimes at scene brightness changes. I am not certain whether it is a change in the fan noise or sthng else, and maybe it is normal and was always like that and I just don't remember (pj had been left unused for a bit less than 4 yrs).

Playing through HDfury3, only settings it would lock onto was 1080-50p (RGBHV) and 1080-48p(YPbPr). In YPbPr I had to scale horizontally to 46% (HD4000). I set HDfury3 to RGBHV and connected with 5BNCs.
Edited by georg - 2/11/13 at 1:06am
post #23 of 25
Nothing else will be causing this. You have a number of bad HV parts. That's why I run any one I sell here for a minimum of 12 hours. Sometimes one HV part seems to affect another one within the set, as a few times now I've had to swap out the whole EHT section with a known tested one here. It's happened more than once, not sure why.
post #24 of 25
Thread Starter 
Do you mean that if one of the trio (eht, quadrupler, splitter) is bad it might cause damage to one of the other two?
post #25 of 25
It's not likely, but it's possible, That's why I'm suggesting you send me all three to test here, and if I blow something up on my test set, that's then MY problem. smile.gif
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