Film-Tech Forum ARCHIVE: How can move 3D Dolby ?

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Posted by Peter Provorov (Member # 8455) on 11-09-2014, 10:21 PM:

I have Projector Barco DP2K-20C and DP2K-12C.
I want to move 3D Dolby form DP2K-20C to DP2K-12C,
Everybody can help me do it ?

Please guide me.
Thanks.

Posted by Steve Guttag (Member # 268) on 11-10-2014, 06:02 AM:

There are a couple of problems with your plan...

That involves pulling the light engine, moving the 3D adapter and a cable. You'd also need the normal cooling block for the 20C...which you likely don't have anymore and the 12C doesn't have (so you can't swap them).

The other problem is I doubt that the 12C will have enough light for whatever screen you want to put the Dolby 3D on unless it is VERY small. Dolby 3D eats up the light a lot.

Posted by Peter Provorov (Member # 8455) on 11-10-2014, 08:05 PM:

Thanks Steve,

I checked with lens caculator, and it is enough light.
How can i get the normal cooling block for the 20C ?
I don't have it because when i purchased projector include 3D Dolby.

Posted by Steve Guttag (Member # 268) on 11-10-2014, 08:40 PM:

I couldn't tell you...I've never needed one. Barco is not always good about their spare parts. Sometimes, one has to get entire assemblies to get the part one wants...unfortunately, around the light engine...that often means the light engine itself. But you could always contact your local Barco service/supply company.

Posted by Monte L Fullmer (Member # 2797) on 11-10-2014, 10:29 PM:

Wouldn't it be simpler and easier if one just moved the entire 20C unit to the smaller house and just swap lenses between the two units?

Posted by Peter Provorov (Member # 8455) on 11-10-2014, 10:30 PM:

Thanks Steve.

Posted by Magnus Eriksson (Member # 6085) on 11-11-2014, 03:06 AM:

I have several used cooling blocks in the back of the car. I can´t be the only tech in that situation.
Check with your local Barco dealer/tech. If yoú´re out of luck send me a PM. Moscow isn´t that far away.
Swapping Dolby 3D-units on your own isn´t advisable if you´re not used to it. It can be a very expensive experience [Frown]

/M.E.

Posted by Peter Provorov (Member # 8455) on 11-11-2014, 10:31 AM:

HI Monte,

I just only remove 3D Color wheel from 20C to 12C,
I checked wtih soft Lenscacular.

Posted by Marco Giustini (Member # 4544) on 11-11-2014, 01:43 PM:

lens calculator are usually quite enthusiastic when it comes to Dolby light efficiency. I would measure the light you get out of your current setup, set the lamp to 100%, take a reading in 2D and then in 3D with the same lamp power. Do the math to find out the efficiency.

Then take a reading where you have the 12C and you can predict the final result.

The lens calculator may say you can do it, Steve is an experienced cinema installer. Who are you going to trust more?

Posted by Dave Macaulay (Member # 813) on 11-12-2014, 07:28 AM:

The lens calculators are usually optimistic, true. Without information on screen size, any "experienced tech" is whistling into the wind opining on whether the 12C is sufficient.
However, swapping the projectors makes a lot of sense. It is NO FUN putting Dolby 3D into a Barco C projector. If the 20C was lighting its screen decently for Dolby 3D, a 12C should definitely be enough for 2D there - assuming you're abandoning 3D on that screen.

Posted by Marco Giustini (Member # 4544) on 11-12-2014, 04:16 PM:

I reckon you cannot install a 12C with Dolby 3D on more than on a 4.5m wide screen. And this is with everything at 100%, so to have some headroom to compensate for lamp and ageing, shall we say 3.5m?

Posted by Steve Guttag (Member # 268) on 11-12-2014, 04:55 PM:

I believe I did qualify my statements from the get-go. I'm merely skeptical that the 12C would, in fact, be sufficient. Naturally, one would need to know the desired light, screen size, gain...etc. to make a full evaluation. But given that the 12C with the most optimistic lens is around a 11,000 lumen projector with a 2.2KW lamp running...you are going to be a bit pressed for light on all but the smallest screens with Dolby 3D.

Posted by Peter Provorov (Member # 8455) on 11-12-2014, 10:39 PM:

Thanks all,

My screen is: 6,3m X 2,3m

I belive Barco 12C enough light when i install 3D Dolby..

Posted by Dave Macaulay (Member # 813) on 11-13-2014, 04:19 AM:

Your lens calculator seems very optimistic. What loss factor is used for 3D?

Posted by Dave Macaulay (Member # 813) on 11-13-2014, 06:39 AM:

From the Barco lens calculator, a 15C is the smallest projector suggested for that screen size using 50% lamp life, 1.55 gain screen, Dolby 3D, and 2.5% optical loss. Dropping the screen gain to 1.00 (a perfect matte white screen) takes it up to a 4kW 23B as minimum.

Posted by Steve Guttag (Member # 268) on 11-13-2014, 09:17 AM:

My own calculations are less optimistic...particularly if you do a full light balance to each eye...you'd be lucky to get 8% efficiency. Even with a 1.8 gain screen, the 12C isn't going to get 4.5fL for the life of the lamp...even using a 2.2KW lamp.

However, if you can accept it getting down to 3.5fL for Scope and a 2.2KW lamp and have a 1.8 gain screen (more hot spotting)...then it could work. With an anamorphic lens you'd improve your scope light by 23%. But my guess is that one that is quibbling over a 12C versus a 20C (that you already have) that an anamorphic is not a realistic option.

Posted by Marco Giustini (Member # 4544) on 11-13-2014, 12:53 PM:

forget about that