Barco 32B Focus issue

[Jay Glaus]

Steve, what bit do I need for the driver?

[Marco Giustini]

As Steve says, the lens mount of the B series is not the finest item designed by Barco.
What you may be seeing is a slight vibration on the lens which looks like blurred details on screen. If you tried a smaller lens - that is, lighter - it may make things less noticeable. The kit Steve recommends is indeed good and should be offered as standard on such expensive projectors.

One thing that happened to me on a Barco was that the engine was somehow losing sharpness when the lamp was turned on - and could not be corrected. Definitely an engine issue as another lens would not improve, it was not vibration or scheimpflug and a new engine fixed the issue. It was obvious by calling a green pattern BEFORE the lamp was turned on, then I would turn the lamp on while looking at the screen: patterns would be razor sharp for a 30-45 seconds and then slowly getting blurry - but focus could not be adjusted via focus control.

You may want to check this as well just in case but glad you ordered the stabilisation kit, that cannot hurt your lens mount!

[Leo Enticknap]

Maybe a formatter loose on the chassis, and that was what set up the vibration?

Had something similar happen on an SP4K in September.

It had been powered down for 18 months during the pandemic (in a university lecture theater and the kids were having their lectures on Zoom), and when they powered it up again, there was an absolute blizzard of stuck pixels - something like 15, on all three colors, and 24 hours of the alternating checkerboard didn't shake any of them loose. Thankfully, the projector was just still in warranty, so Cinionic shipped a new light engine. After installing it, I could only just converge the red: i had to screw one of the adjusters hard to the end of its travel, and even then, it was barely converged. And I could not achieve focus uniformity with the red, either. It didn't matter how many times I followed the drill taught to us in the training school (screw all three Scheimpflug adjusters down until just snug, back them off two revolutions, lock off the bottom one, then adjust the other two until focus uniformity is achieved): for the red pixels, either I could get the top left in focus, or the bottom right, but not both.

When I felt the formatter board for the red DMD, it was very slightly loose - it did not feel snug. They shipped yet another light engine, which I had properly converged and Scheimpflug-ed within half an hour and with no problems.

Incidentally, one gotcha with swapping out an SP4K light engine is that you need a long T20, such as this one, to release the three screws holding it to the chassis. Without it, you're dead in the water. The holes it has to pass through are too thin for a socket driver extender shaft: it has to be a thin screwdriver.

[Steve Guttag]

I carry that torx driver with me at all times. That one tool opens about 90% of SPxK covers too. One nice thing about the SPxK series is there is a minimal amount of tools needed to work on it. Also, the light engine, which Leo got some practice with, it would appear, is many times faster to swap than S2 projectors (I had a single stuck pixel in one of mine...oddly, it was red I had to converge too but it came right in and there were no focus issues).

As to an image getting blurry 30-seconds after start up...I'd suspect that a fan that is ramping up after turning the lamp on is vibrating the light engine...particularly if an external in-line fan is not isolated on the projector.

I don't have the hex bit memorized for that screw (it is an M4 screw so whatever hex would normally fit inside that...something like a 2mm?).

[Marco Giustini]

As to an image getting blurry 30-seconds after start up...I'd suspect that a fan that is ramping up after turning the lamp on is vibrating the light engine...particularly if an external in-line fan is not isolated on the projector.

Must have been one of the fans on the engine itself as a new engine solved the issue (only for several months if memory serves...). It was a bizarre issue indeed.

Leo
A bunch of dead pixels on all three colours is likely a laser pointer. I'm not sure about stuck pixels to be honest.

[Tony Bandiera Jr]

Maybe a formatter loose on the chassis, and that was what set up the vibration?

Had something similar happen on an SP4K in September.

It had been powered down for 18 months during the pandemic (in a university lecture theater and the kids were having their lectures on Zoom), and when they powered it up again, there was an absolute blizzard of stuck pixels - something like 15, on all three colors, and 24 hours of the alternating checkerboard didn't shake any of them loose. Thankfully, the projector was just still in warranty, so Cinionic shipped a new light engine. After installing it, I could only just converge the red: i had to screw one of the adjusters hard to the end of its travel, and even then, it was barely converged. And I could not achieve focus uniformity with the red, either. It didn't matter how many times I followed the drill taught to us in the training school (screw all three Scheimpflug adjusters down until just snug, back them off two revolutions, lock off the bottom one, then adjust the other two until focus uniformity is achieved): for the red pixels, either I could get the top left in focus, or the bottom right, but not both.

When I felt the formatter board for the red DMD, it was very slightly loose - it did not feel snug. They shipped yet another light engine, which I had properly converged and Scheimpflug-ed within half an hour and with no problems.

Incidentally, one gotcha with swapping out an SP4K light engine is that you need a long T20, such as this one, to release the three screws holding it to the chassis. Without it, you're dead in the water. The holes it has to pass through are too thin for a socket driver extender shaft: it has to be a thin screwdriver.

Would this happen to be a theatre we both know?

As for the OP's focus issue, a colleague and I had a similar problem with a Christie in a Bel Aire room, the focus issue was caused by a vibrating duct booster fan. It wasn't vibrating much at all, but it just happened to be the right amount at the right frequency to shake the lens mount and light engine to blur things up.

[Jay Glaus]

Ok so here’s an update. I got the new stabilizer and put it in. Wasn’t really that bad to do. I took it slow since I wasn’t sure exactly what to expect, but steve is right about doing it once, if I did it again I could have that wiped out in about 20 mins.

That new stabilizer definitely tightened up the lens for sure. There’s way less movement in it now. After I got it in, I re-homed, Scheimpfluged, and re made screen and lens files, and I really believe this fixed my problem. I was able to get my focus perfectly uniform, and it stayed that way even after playing around with lens a tad to make sure. My focus is SHARP.

I’ll also say this, while I don’t think the general public would notice this, I personally believe it was able to get my picture sharper than when I first got this machine. I think I always had a tiny amount of vibration in my lens and just never noticed it. I’m not saying that was what caused my problem. I think I had some type of movement or sag in my lens, but now I have zero vibration which let me get it perfect.

I feel like anyone out there who has a big lens in their B series could benefit from this part if they don’t already have it.

I’ll post an update after a week or two and make sure it stays in, but I don’t think for a moment honestly that it will come back out. It just felt different this time around.

Thanks to everyone for your opinions and offering all the advice!

[Jay Glaus]

Thought I should post for anyone that hasn’t seen this gem yet that might just come across this post, the one closest to camera is the old one, and farthest is new one. New one is definitely more beefy prone to much less movement.

[Marco Giustini]

Jay - indeed the factory lens "stabiliser" for the B series is a joke.

That said, do you happen to have a fan directly attached on top of the projector? That would make the lens vibrate with the old stabiliser (a lot). Even with the proper stabiliser, I'd still recommend decoupling the fan from the projector - you only need a piece of metal duct which will act as a spring.

Anyways, very good to hear you resolved the issue!

[Jay Glaus]

Marco,

I was really surprised how under built it was for heavy lenses. I’m sure it’s fine for small lenses, but I can’t see how they would have expected it to hold a lot of weight. Also surprised that the 32b wasn’t built with a tougher stabilizer from its inception since most 32b’s are used in larger applications.

My exhaust is decently far away from my projector on that screen to where most of the vibration in the duct dissipates by the time it gets to my machine. I’m sure I get some, but it’s not too bad. Typically though on any installs I do, I like to splice in a section of flex duct in especially if the fan is close. I find that really deadens a lot of vibration too.

[Marco Giustini]

No, it's not good with smaller lenses either - I mean, it's much better but still a poor design which should not be used on a flagship machine.

As long as the fan is not sitting on top of the projector without anything in between - and as long as the ducting is not 100% rigid - you are fine.

[Steve Guttag]

I would NEVER connect a rigid duct directly to a projector. You will get a vibration unless there is some form of isolation between. It is just too easy to not splice some flex in there.

I don't think I've ever had the vibration issue on the lighter Minolta lenses (the ones that don't stick out so far). That said, I budget in the proper lens mount on all of our DPxK-xxB projectors. It is shameful that Barco continued to use the ball bearing stabilizer once the linear bearing one came out. They HAVE the fix...use it.

[Leo Enticknap]

Would this happen to be a theatre we both know?

Not quite (that is stuck in the stone age with a DP2K-8S!), but a similar sort of place about 20 miles to the north-east.

I use a Wera 05074770001. It is probably more than you will want to spend for just 1 system.

Amazon are currently doing an offer on a similar model (33% off) in case anybody wants to snag one. I need to use a torque limiting screwdriver rarely enough that I have a no-name cheap Chinese one (cost around $30), which has worked well for me so far; but so far at any rate, I've only ever had to work on projector components in which setting accurate fastener torque is critical three or four times a year, and so didn't see the point in investing in a high end one.

[Steve Guttag]

The Wera preset torque drivers are great. I have one set to 2.5Nm for Barco lamp adapter torques. Please note, they are not the same as adjustable torque drivers. The preset torque drivers are designed for set-and-forget (set them once) and rarely, if ever change them. There are no markings on the driver for torque. It comes preset to a torque and by counting turns one can change that using an allen key. One should then mark the driver for the torque it is set to (they have stickers one can put on the end of the driver for this). One should, also, verify the torque setting with a calibrated torque wrench/driver.

A big upside to a preset torque driver is that they cost less and they are always ready for the job at hand. So, if you do a lot of Barco lamp changes, having one with a 5mm hex bit and set to 2.5 Nm, you are good to go for putting on the adapter (or removing) on the "C" lamphouses or S/M Lamphouses and you are also good-to-go on inserting the lamp and torquing down the cathode adapter into the lamphouse itself. You'll always get the torque right and never stress (damage) the softer brass threads.

[Jay Glaus]

It’s back.

Thought the lens stabilizer fixed my problem but sadly I was wrong. Thought the movie looked a little funky last night so I threw up the focus pattern and sure enough, my uniformity is gone. One corner of the screen was bad enough to the point where if you didn’t know it said “Focus” in the middle, you might not have known what the squares said.

I think the lens stabilizer helped me get better focus, but I’m still having an issue with uniformity.

The thing I’m worried about now is I scheimpfluged it last night and I could not get it uniform like before. It’s better, it’s watchable, but it’s not right. You essentially chase a blurry corner around the screen with no end.

I’m running out of ideas with this machine. I’m starting to think something is amuck in the lens turret.