Film-Tech Forum ARCHIVE: Spinning wheel goes bang

This is topic Spinning wheel goes bang in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Phil Ranucci (Member # 3820) on 06-16-2009, 10:37 PM:

Well our recently installed Barco DP2000 lost its Dolby filter wheel today. Have to say not a big pile of glass shards for the money.
I get to see it being replaced tomorrow. Anybody else have one break?
We are not amused.

Posted by Brad Miller (Member # 2) on 06-16-2009, 10:39 PM:

Was there a bulb explosion? Was the wheel not properly tightened down?

Posted by David Stambaugh (Member # 1102) on 06-16-2009, 10:47 PM:

Spinning wheel in brand-new $100,000 state-of-the-art digital projector = Me laughing. I'm sorry, I know it's not funny, but still...

Did it break during a show? What does the image look like when this happens?

Posted by Jon P. Inghram (Member # 4125) on 06-16-2009, 11:02 PM:

At least the projector keeps the shards from flying and cutting your head off. Every time I get close to our MasterImage's whirling Disk-of-Doom I expect it to explode and send shards of plastic into my eyes. [Eek!]

Posted by Sam D. Chavez (Member # 1841) on 06-17-2009, 01:41 AM:

I have a DP2000 with Dolby color wheel giving a "color spin error" in the log every so often.

You push the 3D button on the projector again even though it's already on and the picture returns to normal.

So far no one at Barco has a clue what his means.

Posted by Mark Gulbrandsen (Member # 72) on 06-17-2009, 03:23 AM:

quote: Phil Ranucci
Anybody else have one break?

Yes,
I've had one disentegrate but because of a lamp explosion. Glass shard from lamp went right through the heat filter on a CP-2000 and also took the wheel out. Had to replace Reflector, Lamp, Heat filter and Dolby wheel. I think the parts tab was somewhere around 20K for the whole clean up. I hope your's is under warranty since the wheel carries an almost 14K list price!!! This is very definately THE system where theater owners may want to consider carrying equipment insurance.

Mark

Posted by Steve Guttag (Member # 268) on 06-17-2009, 06:49 AM:

I don't think a lamp explosion on a Barco could get to the Dolby wheel, Brad. In a Barco, the lamp sits 90-degrees to the Dolby wheel. Also, the Barco lamphouse pretty well holds/contains lamp explosions.

Steve

Posted by Mark Gulbrandsen (Member # 72) on 06-17-2009, 08:47 AM:

It would depend on how well the heat filter holds up... how thick it is and so on. The Barco's I've worked on don't have as thick of filter as in a Christie. Glass shards could certainly bounce off that right angle mirror if they make it through the heat filter and then take out the wheel. Then there is the concusive factor of the lamp explosion itself... they say a 2kw is equal to one stick of dynamyte! A 6kw lamp is going to be a much higher powered explosion. That is one factor one can't get away from no matter what... that Dolby wheel is VERY thin! Either of these scenerios is certainly possible and I don't really see much less of risk because of the right angle mirror. Another point is that right angle mirror in there (and on NEC's) is why they don't put out as much light as the competition does which can cause one to go to the next higher wattage lamp and up the operating expenses.

Mark

Posted by Hendarto Ciputra (Member # 4868) on 06-17-2009, 11:14 AM:

In the DP2000 there's another mirror at the opening after the reflecting mirror this further reduce possibility of breaking the wheel. On the other hand, i encountered a deffective dolby that went bust on first activation. Claimed it under DOA and get replacement within a week

Posted by Ian Parfrey (Member # 5122) on 06-17-2009, 12:57 PM:

Spinning colour wheels??? Sounds like a throwback to the days of multi-coloured front shutter projectors of the 1920's!

Why the wheel? Surely a pulsed dichroic lamphouse similar to a telecine would be more efficient/effective..and at $20K, most likely cheaper too?

Without seeing one of these units, I have to admit to being a [dlp]

noob, so please excuse my ignorance.
Cheers
Ian

Posted by Jack Ondracek (Member # 1466) on 06-17-2009, 01:07 PM:

quote:
they say a 2kw is equal to one stick of dynamyte!

Ahhh... Living in an area where several groups of Indian descent sell dynamite for a living (creatively relabeled as fireworks), I'm fairly sure there isn't a lamphouse on the planet that would survive a full stick explosion... much less the surrounding projection room.

Posted by Monte L Fullmer (Member # 2797) on 06-17-2009, 01:13 PM:

...maybe an M-80, or a cherry bomb ..., Now, when a LTi Helios goes, they are a bit more nastier due to the higher compression inside the bulb.

Posted by Martin McCaffery (Member # 37) on 06-17-2009, 01:34 PM:

quote: Jack Ondracek
I'm fairly sure there isn't a lamphouse on the planet that would survive a full stick explosion... much less the surrounding projection room.

Only one way to resolve this dispute: It's video time! [evil]

Posted by Louis Bornwasser (Member # 3063) on 06-17-2009, 01:57 PM:

Where are the Mythbusters when you need them! (lots of flame and loud noise) Louis

Posted by Justin Gorka (Member # 3727) on 06-17-2009, 03:55 PM:

Go with Real D, no spinning wheels here!

Posted by Matt Fields (Member # 3211) on 06-17-2009, 08:11 PM:

Go with Dolby, no licensing fees here!

Posted by John Wilson (Member # 269) on 06-17-2009, 08:47 PM:

No, just small sharp shards of flying glass.

Posted by Phil Ranucci (Member # 3820) on 06-17-2009, 10:11 PM:

Actually the glass was contained inside the projector.
No lamp explosion, the disc just shattered. Took about 2 hours to replace and reset the 3-D settings.
No idea why it went, all's OK now (for now).

Posted by Steve Guttag (Member # 268) on 06-17-2009, 11:22 PM:

It appears that Barco's "lamphouse" really does do a decent job of containing even 6KW lamps kabooms...the reflectors don't survive very well...but the heat filter does seem to survive.

Steve

Posted by Mark Gulbrandsen (Member # 72) on 06-18-2009, 12:47 AM:

quote:
Go with Dolby, no licensing fees here!

Dopn't think you're not paying for it!!! It's burried in the cost of the gear... at least it's a one tme fee unless your's breaks...

Mark

Posted by Joe Redifer (Member # 3) on 06-18-2009, 01:28 AM:

Spinning wheels? I thought d-cinema was supposed to be awesome with no moving parts and whatnot. LOL @ spinning wheels.

Posted by Steve Guttag (Member # 268) on 06-18-2009, 06:31 AM:

It goes with the jiggling mirrors!

Posted by Matt Fields (Member # 3211) on 06-18-2009, 08:26 AM:

I doubled checked, I have my projector (Christie ZX) insured against all risks, so if the wheel does go, I'm only out my deductable. Of course, I am paying extra premium.

The cost of the licensing fee, in the long run, is far greater then the cost of the gear and the premiums.

Posted by Mark Gulbrandsen (Member # 72) on 06-18-2009, 08:28 AM:

quote: Matt Fields
I doubled checked, I have my projector (Christie ZX) insured against all risks

Good idea and I reccomend to all purchasers they either go with the extended warranty or buy the insurance! Did you also buy Christie's and Dolby's extended warranties on the equipment at the time you purchased it?

Mark

Posted by Matt Fields (Member # 3211) on 06-18-2009, 08:31 AM:

I am going to get the Christie. I was told I have two years to purchase the extended.

I also insured the glasses against all risks (including theft), so as time goes by and I eventually do need to replace, it will only cost me 100 bucks. - Matt

Posted by Evans A Criswell (Member # 381) on 06-19-2009, 09:20 AM:

I have some information about the spinning color wheel that was tried for early color TV, but never could find the exact year it was developed, and am curious. Anyone know?

It's amusing that this old technology that was not chosen for our color TV system came back years later.

What goes up must come down
Spinning wheel got to go 'round
Talking 'bout your troubles it's a crying sin
Ride a painted pony let the Spinning wheel spin

Sorry, couldn't resist....

Posted by Phil Ranucci (Member # 3820) on 06-19-2009, 10:22 AM:

So whatever happened to David Clayton Thomas?

Posted by Paul Mayer (Member # 355) on 06-19-2009, 12:41 PM:

For Evans,

The CBS field-sequential color system was developed during the 1940's and was proposed several times as the US standard during that decade. It was briefly adopted as the US standard by the FCC in 1950 but was killed off in 1951. The RCA system became the US standard in 1953.

CBS Color System Chronology

For Phil,

David Clayton Thomas is alive and well and still touring across Canada. BS&T was just here Memorial Day weekend performing at the Fremont Street Experience. AFAIK, David Clayton Thomas was not part of that performance.

2009 Tour Schedule

/hijack

Posted by Damien Taylor (Member # 4255) on 06-19-2009, 07:46 PM:

An even more appropriate excerpt

Just let it shine within your mind
And show you the colours that are real

Posted by Mark Gulbrandsen (Member # 72) on 06-19-2009, 07:54 PM:

Here are two links to photos of actual off air pictures and the original photo that was televised. It's easy to see why the FCC initally adopted the CBS system...

Actual off air CBS system color pictures

Actual off air photograph of RCA Color System and original photograph broadcast