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Posted by Jonathan Bodge (Member # 4072) on 11-16-2008, 04:27 PM:
 
I saw in a booth here in Connecticut a "Master Image" spinning disk 3d rig that sits in front of the video projector lens. Any of you seen the results with this apparatus at Showeast?
 

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Posted by Mark Gulbrandsen (Member # 72) on 11-16-2008, 05:48 PM:
 
Yep, Its good but no better than any other single projector 3-D system... Two projectors still provide far better results. I'm puttn one of these in next month so I could report back then! Its also very expensive but utilizes CP glasses....
 

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Posted by Jonathan Bodge (Member # 4072) on 11-19-2008, 06:33 PM:
 
I am anxious to get Marks reviews on this, I also find it somewhat humorous that in this whole wide world he's the only one who responded...can't be too popular.
 

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Posted by Mark Gulbrandsen (Member # 72) on 11-19-2008, 07:23 PM:
 
JOnathan, Its quite expensive! In the mid 30's. I still feel the Dolby 3-D system is the better way to go in spite of the 7 grand dishwasher.

Mark
 

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Posted by Frank Angel (Member # 248) on 11-19-2008, 09:31 PM:
 
Mark, is that dishwasher required by Dolby or can the theatre go with a more conventional washer. Surely there are commercial restaurant washers that can clean as well as whatever this uber expensive unit can do.
 

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Posted by Tristan Lane (Member # 1169) on 11-19-2008, 09:46 PM:
 
Any commercial low-temp dishwasher will work.

Hell, you can use a standard undercounter low-temp dishwasher to sanitize the glasses as long as you use the proper chemicals.

We use our bar glassware dishwasher to santize the glasses. I've seen these on Craigslist for as low as 500 bucks. I DO recommend a booster heater (as dolby does) so that you avoid spotting.
 

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Posted by Mark Gulbrandsen (Member # 72) on 11-19-2008, 10:11 PM:
 
Frank, I was told that there is actually a theater in Spokane doing it all by hand in a triple basin sink... but still using the proper chemicals so it meets health standards.

This dishwasher is very similar to what Dolby reccomends right down to the three chemical metering units on top.

I was told by one of our customers that the key to the whole thing is to have a 50 gallon hot water heater for what ever dish washer you use and as Tristian mentioned the proper chemicals... they should cost you under 200 bucks for the three 5 gallon pails total. They will last a very long time. The dishwasher Dolby reccomends only usees 1.5 gallons of water per cycle.

Tristian... if you could specify a model number on that dishwasher it would be greatly appreciated.
 

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Posted by Tristan Lane (Member # 1169) on 11-20-2008, 01:13 AM:
 
The exact model we use is an ADS Dishmachine ET-AF

Instawares link is here

This unit is listed at 3000. Street price is less than that. I picked up a used one that I have for parts for 400.00 from a reastaurant nearby that was closing.
Any low-temp 3-chemical unit will work. As long as the water is at 160 degrees or better, spotting shouldn't be a problem if you use the rinse agent and have soft water. The chemicals specified by Dolby are a detergent, rinse-aid, and sanitizer. All traditional low-temp restaurant units use similar chemicals.

Edit: I might also add that many restaurants out there lease their dishwashers for a monthly rate and price-per-load fee with chemicals and maintenence included.

I think IN3 (the active glasses 3D company) was actually marketing a residential grade "modified" Fisher & Paykel dishwasher for sanitizing their activie glasses.
 

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Posted by Mark Gulbrandsen (Member # 72) on 02-05-2009, 06:31 PM:
 
This week I installed the Master Image 3-D system along with a tech from Master Image. All went pretty well except that the DP-100 was a very early unit and it required a new card cage backplane. The Master Image needs the pulse from GPIO-1 to sync and the old backplane wasn't intended to output this pulse... pre 3-D days of 2K stuff! However, and for you people that preach the obsolescence of D-Cinema gear... BARCO graciously supplied the new backplane free of charge. Once the backplane was installed and the BARCO re-assembled (no small task), the Master Image synced right up and worked beautifully.

Build quality of the Master Image is very high and the spinning disk drive motor is direct drive and utilizes a brushless servo drive system of very high quality.

How does it compare to other 3-D systems??? I have to completely take back what I said in my post above... This is NOT EQUAL to other single projector 3-D systems... it is FAR SUPERIOR... Simply put, this is THE BEST single projector 3-D I have seen to date and also the brightest. We acheived 5.7 fl with just a 4kw cinema type lamp (not a short gap) running at about 80%. I know there are downsides to Silver Screens which this system does require but the upside of the super high quality 3-D easily makes for putting up with the silver suurface. We hung a new type Hurley "washable" silver screen at this location in preperation for this install late last year. This screen has been tested by Master Image's technical staff whom themselves are involved with testing every toher 3-D system out there for DCIP.. in short they are way overqualified to do this sort of testing. Their conclusion was very positive and even Coke spills on this screen won't damage it's surface.

So combine the new Hurley Washable Silver Surface with the Master Image 3-D system in front of a full frame triple flash projector and you'd have one killer 3-D system that easily knocks the socks off the rest of em. This one certainly does.



Mark
 

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Posted by Julio Roberto (Member # 4976) on 02-06-2009, 09:09 AM:
 
Glad to hear a decent alternative to R€al-d exists that can use inexpensive polarized glasses.

I would imagine the ghosting to be about the same (or better) than Real-D as well. Dolby would still be champion here, but at a significant light loss and worse colour space.

And the Master Image would be cheaper too.

I would recommend this system for those not willing to go the dual-projection route until Dolby glasses come down to a price point that the profits truly offsets the inconvinience and risk.

Thanks for your report, Mark!!!!
 

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Posted by Mark J. Marshall (Member # 1409) on 02-06-2009, 09:55 AM:
 
What does the spinning disk do exactly? Is it basically performing the same functions as that z-screen thing and alternating between circular polarization directions?
 

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Posted by Julio Roberto (Member # 4976) on 02-06-2009, 11:03 AM:
 

quote: Mark J. Marshall

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What does the spinning disk do exactly? Is it basically performing the same functions as that z-screen thing and alternating between circular polarization directions?

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No more, no less Just a left and right circular polarizer mounted on a disc made to spin in synch with the projector so that 144 times a second the top part covers the image area in either left or right direction.

And yes. It spins FAST.

How noisy is it (i.e. the engine), Mark? Obviously less than a 35m projector ... but just wondering if it sounds like a high speed fan or it's actually really quiet.
 

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Posted by Monte L Fullmer (Member # 2797) on 02-06-2009, 01:17 PM:
 
Have a peek on this product here.

Yet, kinda funny: First - we return to the "sound on disk" format being DTS. Second - we return to the front shutter of an old Powers 6B projector ...

..I find that a bit amusing..

-Monte
 

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Posted by Mark Gulbrandsen (Member # 72) on 02-06-2009, 03:46 PM:
 

quote: Julio Roberto

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And yes. It spins FAST.

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quote: Julio Roberto

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plus $200 for filters

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quote: Mark Gulbrandsen

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Show me decent CP filters large enough to properly dissipate heat that cost only $200.00... they don't exist... try more like $1200.00 a filter for 11X14 inch AR Glass size which is the minimum size the CP filter manunfacturer we used reccomended for 4kw D-Cinema and up.

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Here there is a linear plastic 8.5" x 15" for $37 retail

http://www.edmundoptics.com/onlinecatalog/displayproduct.cfm?productID=1912

You can laminate it in glass if you want. If you want them circular, just add a $10 retarder film.

If you want to buy them already made glass circular, I've seen them in 8x8 for $120, don't quite remember where. Here is a place with all kinds, including a 6x6 inches circular glass PAIR for $465. This is for a PAIR of them, circular, glass, and for use in projection.

http://www.berezin.com/3d/filterholder.htm

First one I found with google. FAR LESS if you go straight to a polarizer manufacturer. I used to purchase full sheets (something like 4 by 2 feet) from Polaroid for like $100.

Here are acrylic, circular, 11"x15" for around $150. They also do glass, if you want, but acrylic is just as good for this use, as it's being used in the Master Image you love so much. This is full retail.

http://www.apioptics.com/circular-polarizers-spec.html

Here is a glass, AR, circular polarizer, aprox. 11"x15", 3M manufactured one for $182. Made for high resolution monitors, so it must be good optical quality. Basically satisfies your requirements, although not for the intended use, but shows it can be (easily) sold retail at those price levels.

http://www.officemax.com/omax/catalog/sku.jsp?skuId=20367381&cm_mmc=GBa se-_-Technology-_-Computer_Accessories-_-Glare_Screens_Privacy_Filters&ci_src=14110944&ci_sku=20367381

Remember in the 80's a small piece of polarizer in front of mirror boxes, prismatic adapters or even in front of split lenses (i.e. less than 3x3 inches) was taking all the heat from the (say around 3K, dual-blade shuttered) projection lamps.

Sure they suffered, but replacing them every couple of years was a good quality assurance method and at $50 or so for a pair of small linear, a good choice.

For 4KW digital, I'd say use anything glassed over 6"x8" and just change them regardless of usage every so many years. $200 each could do just fine if you know where to find them or purchase quantity from manufacturer. I just meant my $200 figure as a generic thing, plus I was referring to linear (thus the 75% improvement in extintion ratio). But you could go anywhere from $10 for a small piece of plastic linear to $1000 for a large piece of glass circular, of course.

11x14 is overkill for 4kw, but good if you want them to last for 100 years Not even RealD's zscreen is that large size, it's more delicate, retains more light (heats) than a passive filter and it's used with projectors up to 7Kw all over the country ... not even Imax 15kw used filters that big of a size ...

http://www.youtube.com/watch?v=AKr7yS9Rx6I

... still, I could do circular, glass, 11x14 for $200 easy. It's just not your average standard product that I can point to a web site with a price on it. I would have to custom make it (my cost pbbly $30-$125, depending on materials used) or custom order it to have it made for me (pbbly at quotes of less than $350 each if I order a pair).

But to be honest, this is not entirely true. Depending on the manufacturing process used in the polarizer, this would either quickly degrade with time if light is shined through it (noticeable in just a few years, useless, less than 60% as effective in as little as 3 years), or almost not at all, even if subjected to large luminous flux . Projection zscreens are made with a wire grid polarizer, so they are not anywhere nearly as delicate as those made with organic materials, iodine or dyes and can survive easily huge fluxes in small(ish) sizes.

My advice: just get a reasonable (say start at 6x8, go up to 10x12) inexpensive filter and replace it "often". Also, circular retains more light than linear due to the two optical surfaces, so it needs a bit larger area to "suffer" the same as linear. About 4-8% more, depending on manufacturing process used.

Or use a wire grid polarizer and you can have a small size and still have it last "forever". Add a retarder if you want it circular (retarders absorv very very little light ... any reasonalbe size, even the size of the lens, would cope with the flux w/o problems after the polarizer).

And at $1200 for a 11"x14" circular filter it's way too expensive ... for that price you could almost purchase a whole zscreen 13"x17" ACTIVE ZSCREEN, which includes a high quality glass circular polarizer that "alternates right and left" to cover a 21" diagonal high resolution monitor, including two pairs of quality fashion circular glasses, power supply, monitor interface, etc .... at full retail ...

http://reald-corporate.com/scientific/zscreen.asp

Honestly, a zscreen can be manufactured for PEANUTS and polarizers, specially linear, for peanut's shells. But as I've said before, manufacturing COST and selling prices are entirely different things.

I would be very surprised if the filters in the Dolby wheel don't degrade with time in the highest lamped models (where they'll be mostly used). It will depend on the manufacturing materials used, so it is NOT necessary for them to degrade, but somehow I feel they didn't go the exotic materials route.

I would also feel that the Master Image filter would degrade, but not nearly as much. They probably made the right choice of use inexpensive iodine filters and just have the wheel changed every so often. My totally wild guess: every 2-4 years of daily use on high power projectors. Since 3D movies are not a daily thing yet and not all projectors are 6Kw ... pbbly less often.

How much is the retail for the Master wheel, Mark?

For once, the Dolby baby receives the raw light and heat, absorbs around 73% of it, doesn't benefit from the 7% "black period", lives inside the "heat case". RealD-zscreen/Master-disc receive the light after it's gone through the whole optical system and lens, retains only about 58% of the (remaining) light, benefits for a 7% dark period rest, and spreads the flux over a larger lighted area while cooler outside in the booth or rotating like the Master.

[EDITED to add more websites were similar products can be bought at those price levels plus add more rant ... please, re-read the whole thing ]

[ 02-07-2009, 10:23 PM: Message edited by: Julio Roberto ]
 

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Posted by Mark Gulbrandsen (Member # 72) on 02-07-2009, 10:07 PM:
 

quote: Julio Roberto

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but somehow I feel they didn't go the exotic materials route.

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quote: Julio Roberto

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I would also feel that the Master Image filter would degrade, but not nearly as much. They probably made the right choice of use inexpensive iodine filters and just have the wheel changed every so often. My totally wild guess: every 2-4 years of daily use on high power projectors. Since 3D movies are not a daily thing yet and not all projectors are 6Kw ... pbbly less often.

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quote: Mark Gulbrandsen

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Actually the Dolby Wheel is THE most exotic of the 3-D filters made! It has over 30 vaccum deposited layers of two different segments on the disk

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quote: Julio Roberto

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but wonder if they really can take 6kw even if spinning for "ever" or would need replacement ...

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quote:

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Sorry but you can't make filters that are polished to quarter wave, have AR on them and just 4mm total thickness unless you have similar factory conditions. The reason for largish filters is to spread the heat over a large area so the filters have a very long life, the glass also helps greatly to not only filter the remaining UV and IR light but also absorbs the heat before the plastic filters do.

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I can source 1/8 wave AR optical glass and laminate thin films on them with necessary precission with the result of slightly over 4mm total thickness for circular if I needed to. Easier to let a polarizer manufacturer do it (as you did with Colorlink), since it's their bread-and-butter and setting up for it is not worth it unless I make a couple hundreds run.

I agree and recommend glass for the reasons you mention (additional light loss, but greater UV and IR rejection and heat spreading/absortion of additional mass, plus durability and easy cleaning), but such large size is not necessary for 4Kw, but it never hurts to go over-specs than under-specs.

We've already gone thru RealD being circular or not. All retarded polarization is elliptical, with circular being one of the cases for it. The only difference is how you align the retarder and the polarizer. You align fast/slow axis perfectly perpendicular with the polarizer and you get perfect circular. You rotate the retarder a bit ... you get elliptical ... a bit more ... more elliptical ... a bit more ... until you are back to were you started

It just means that RealD decided, for whatever technical or marketing reasons, not to align the active retarder and the polarizer to 90º, but 45º or another in-between angle. So the only problem is that the manufacturer of the glasses (colorlink) for RealD compatible systems would have to rotate the retarder to the correct angle to make the CP filter work with their Zscreen.

[ 02-07-2009, 11:44 PM: Message edited by: Julio Roberto ]
 

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Posted by Matt Fields (Member # 3211) on 02-07-2009, 11:52 PM:
 
With Master Image, does the exhibitor pay for the disposable glasses? If so, how much do they cost?
 

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Posted by Julio Roberto (Member # 4976) on 02-08-2009, 12:42 AM:
 
Regular standard Circular polarized paper glasses can be bought in the open market for less than $0.40 each in small quantities. I hope Master Image made the polarizing filters standard circular.

Alternatively, you can buy "theme park style" or "dolby style" reuseable plastic circular polarizing glasses for less than $4 in small quantities. You could collect them, wash them, and re-use them. If they get stolen or lost or broken, not too big of a deal ... certainly not as bad as with Dolby or Xpand

If you commision a huge run from a chinese manufacturer, certainly less than half, even 1/4th, of those prices quoted.

For those that would use a dual-projection linear polarized system, the advantages with respect to circular would be:

-Better extintion, less ghosting. About 75% improvement.
-Better transmission, more light. About 4% improvement.
-Lower filter projection costs. $200 should easily do it.
-Lower glasses cost (i.e. 30-50% less than quoted above).

Main dissadvantage: cost of two projectors (but they could be two smaller models, as the light output is more than "doubled") and the audience needs to keep their heads aligned with the screen. Those sitting too far in the corners of a wide theater or those tilting their heads towards their shoulders would quickly start seeing a lot of ghosting.

For those that think that linear is "not acceptable", please remember that most Imax 3D theaters have always been linear, same as 3D in the 50's and the 80's and all current multimillion attractions in theme parks. A little on-screen advertising reminding people not to tilt their heads is usually sufficient.
 

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Posted by Barry Martin (Member # 1376) on 02-08-2009, 01:40 AM:
 
Mark, which tech were you working with and at which location did you install MI? Just curious, as I am currently employed with Bow Tie Cinemas in Hartford, CT and we had an MI 3D system put in a couple months ago. The tech I met was very friendly and was very open to answering all my questions, which were numerous. I am the first to admit I know next to nothing about digital projection as the last few theaters I worked in did not yet have digital, so his sharing time with me was most appreciated.

They did have to make a trip out to replace the motor that raises/lowers the wheel. As he explained it, they were actually putting BACK the original motors because there was an issue with the "new and improved" motors burning out.

In regards to the quality of the 3D, I whole-heartedly agree this is the best system I have seen so far. I have not had the opportunity to see the Dolby setup, but I have watched a few features in ours and could not be happier with the setup, be it 2D or 3D. I had actually been a bit unhappy about us getting digital put in at first, just because I have preferred film for so long. But once I saw this running I was hooked.

As far as the raising/lowering of the spinner goes, we did not have an issue when running Bolt as there are plenty of trailers for 3D kids movies coming out. When Bloody Valentine came out the only trailer that was supposed to be placed and was in 3D was Coraline. As it is we do not run any ads (a Bow Tie thing), so there is typically only 5-10 minutes of previews and then the feature starts. Considering most people are used to having 15-20 minutes of extra time to be late to a movie, running only Coraline for previews and starting the feature 3 minutes after showtime was a bit of a problem.

So we setup the playlist on the Doremi to start a 2D show, play the 2D trailers we had been directed to play, then set in a "black" pattern and set the cue to start the 3D show with Coraline's trailer and the feature.

This works pretty well, and has a strange little side-effect of making the 2D trailers seem to stick out a little from the screen. I would prefer to have a track system as you mentioned, but this is a 17 screen with one person running the booth at all times so I doubt that could happen.

The one thing I am trying to work out (without having to use my technician if possible) is hooking a Blu-Ray into the digital projector/sound system. We have had occasions in the past where a local festival or school wants to rent an auditorium and then had to bring their own digital projector running off a laptop since they had no 35mm copy. The projector itself is not much of an issue as there is a DVI input, but I cannot for the life of me figure out where I could get a cable that goes from the digital coaxial or optical to the I/O on the processor. I certainly don't want to use the RCA left/right I have for the non-sync and just do stereo. Eventually we are planning on using this house as a DVD screening room for off-peak hours. Any idea where I can find what I'm looking for?
 

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Posted by Mark Gulbrandsen (Member # 72) on 02-08-2009, 08:04 AM:
 

quote: Matt Fields

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With Master Image, does the exhibitor pay for the disposable glasses? If so, how much do they cost?

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quote:

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(as you did with Colorlink),

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quote: Barry Martin

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Mark, which tech were you working with and at which location did you install MI?

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quote: Mark Gulbrandsen

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No, we didn't use Colorlink... we used the xcompany that makes the polorizer film they use. There are but two polorizer film manufacturers in the States. A couple of other manufactuyrers use the silver deposited method and the filters they produce are not very large but can take tremendous heat levels.

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Oh, I assumed, since you said you were using the company that did "RealD's". My mistake, sorry. But, unless half a dozen have closed recently, there are more than 2 manufacturers of film polarizer in the US, although indeed lately 90% of them are in Asia.

If you used iodine polarizers, they will indeed inmediately degrade if they ever reach 90ºc. If you used dyes, a bit more, like 110ºc, which, of course, they will never ever reach .

http://www.apioptics.com/3d-projection-filters.html

But, besides metal deposited wire grids or reflective types, there are other dichroic, inexpensive, commercially available film polarizers that are virtually "indestructable" and basically inmune to the browning or fading or yellowing or decay of iodine or dye based ones and don't need some of the optical stack that colorlink's uses for the glass lamination. Actually they are so stable and inert to enviroment and luminous flux they don't need lamination at all.

Similar to this one by 3M, currently the largest US sheet film polarizer manufacturer:

http://solutions.3m.com/KEPolarizer/

As you know, LCD and Lcos projectors, such as Sony's DCinema projector, use polarizers basically the size of their imaging chip/prism assembly (i.e. 1"x1") and still take all the continous luminous flux for years (of each primary color, but still like the equivalent to >1Kw xenon, in less than an square inch i.e.)

Of course, always important to keep UV/IR filters/dichroic reflectors in shape on high-power projectors to protect the rest of the optical system from unnecessary wear.
 

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Posted by Mark Gulbrandsen (Member # 72) on 02-08-2009, 10:46 AM:
 

quote: Julio Roberto

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Oh, I assumed, since you said you were using the company that did "RealD's".

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No, You miss understood. The company that made ours also makes the film that is used in the Z-Screen. The Z-Screen is indeed assembled by Colorlink!!

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Sorry Julio, I buy as little as I can from China. My motto is "Be American - Buy American!

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Your secret is safe with me, Mark . We won't tell that to Master Image, NEC, Barco, Dolby/Infitec, Cinemeccanica, Prevost, Harkness, Sony, Konica, Schneider, Isco, Osram, Irem ...

Doesn't Christie make most of the stuff in Canada?

Just kidding

PD: I know some non-US companies have factories set up in the USA as well ... I'm just joking around, that's all. We don't pre-judge here in Europe and believe in the free market, so we don't mind buying american (or korean or european or chinese, for that matter). Whatever is good and priced right. Or bad but dirt-cheap. Or expensive but incredibly good. Unfortunately most of our stuff around here in Europe is good-but-not-great and priced like if it was made out of gold.
 

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Posted by Mark Gulbrandsen (Member # 72) on 02-09-2009, 09:55 PM:
 
Julio... To make it clearer the only country I have a problem with is China.

Mark
 

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Posted by David Stambaugh (Member # 1102) on 02-09-2009, 10:10 PM:
 

quote:

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My motto is "Be American - Buy American!

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But drive a Land Rover??!!
 

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Posted by Julio Roberto (Member # 4976) on 02-09-2009, 10:12 PM:
 

quote: Mark Gulbrandsen

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To make it clearer the only country I have a problem with is China.

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We all do

Unfortunately (for us, good for them), they'll be the #1 economic and military power in about 20 years, so we better all get used to them
 

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Posted by Mark Gulbrandsen (Member # 72) on 02-09-2009, 10:24 PM:
 
Don't know Julio... they're economic status pretty much parallels ours.. they are also having big economic troubles in China but you don't hear about most of it since the majority of it is suppressed.

Yes, a Land Rover... at least they are our closest Ally. Its been a pretty good Rover too! Ditto for the Hummer.

Mark
 

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