Film-Tech Forum ARCHIVE: Non Ghost Buster or Ghost Buster

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Posted by Desiderio Garcia Ramirez (Member # 1929) on 11-26-2009, 03:12 PM:

Hi all.

I´ve a question about Master Image 3D.

Is Master Image "Non Ghost Buster" o "Ghost Buster"?

Thanks

Posted by Chris Slycord (Member # 4239) on 11-26-2009, 04:06 PM:

As far as I remember, the only system that needed a "Ghost-Busted" file is RealD.

Posted by Julio Roberto (Member # 4976) on 11-26-2009, 04:50 PM:

It's "up to you". If your Master Image installation has very little ghosting (i.e. a "good" silver screen, clean filters and porthole glass, good glasses, etc) you can use the non-ghostbusted version just fine.

The system with worse ghosting performance is Real-D and the only one that "really" needs it. The others "benefit" from it too if they are displaying too much ghosting, but this shouldn't happen, specially with systems like Dolby which are 10x less proned to ghosting than RealD.

MI would be similar in crosstalk (ghosting) performance to Sony 3D or Imax 3D, which are all better than RealD, but still can ghost a little, specially with some setups/movie scenes.

Posted by John Wilson (Member # 269) on 11-26-2009, 04:57 PM:

Desiderio, welcome to Film-Tech.

We need you to please put your posts in the correct forum. All Digital Cinema posts need to go in the 'Straight To Video' forum. The film guys get shitty seeing non-sprockety type posts in the sprockety-type forum.

Thanks.

Posted by John Wilson (Member # 269) on 11-26-2009, 09:35 PM:

See? (moved)

Posted by Desiderio Garcia Ramirez (Member # 1929) on 11-27-2009, 10:04 AM:

We projeted FINAL DESTINY4 and it had a very high ghosting that we haven't see in other movies.
All the DCP that we receive are NGB and MI recommends NGB, but FOX in Spain provides his MI´s DCP by GB ¿?

Thanks for everything

Posted by Brendan Penny (Member # 5041) on 11-27-2009, 03:38 PM:

Master Image does not require any ghost busting.

Posted by Louis Bornwasser (Member # 3063) on 11-30-2009, 09:06 AM:

That's right and less money as well. Louis

Posted by Mark Gulbrandsen (Member # 72) on 12-03-2009, 06:32 PM:

And either type of file will play back just fine... I believe with Dolby also!

Posted by Pete Naples (Member # 761) on 12-04-2009, 06:42 AM:

Correct Dolby does not require ghostbusted content, but will happily play it.

The Stereoscopic Addendum to the DCI spec pretty much says if any one system requires ghostbusting, that's a no no.

Posted by Mark Gulbrandsen (Member # 72) on 12-04-2009, 09:11 AM:

quote: Louis Bornwasser
That's right and less money as well. Louis

Louis,

M.I. is or was in the 30K ballpark last time I installed one... DTS was working at getting the price down a bit more. Dolby is a little over half that without sterilization machine and glasses... the cleaning machine can be had for in the
$3500 ballpark if you shop around but it's wise to still get the racks from Dolby's reccomended source. Then the number of glasses you ultimately initially purchase determines the final initial cost of the Dolby. They are about 30 bucks a pair and last 450 cycles. The glasses per cycle are at about .07 and a cleaning cycle (in Casper, WY) costs them .05 total cost... .12 is alot less cost than a pair of polarized glasses cost from M.I. which were running .75 a pair when purchased in about 1000 quantity. So in the long run Master Image actually costs more. I happen to like M.I.s simplicity and movability but there is also the need to clean the filters on the nipkow disk at least bi-weekly with a micro fibre rag... If you don't clean it eventually it gets so full of stuff that you no longer have 3-D. Proper popcorn ventallation is almost mandatory, one might also want to consoder filtered booth air if you're installing M.I., where the Dolby wheel is already in filtered air, at least in most projectors.

One thing is for certain... these will ultimately become the most expensive booth doorstops in Cinema history!

Mark

Posted by Steve Guttag (Member # 268) on 12-04-2009, 11:53 AM:

I dunno about that...what was the price of the 4-track mag system in the '50s? And what would that be in 2009 dollars?

Then again, it could be argued that 4-track mag had a 30-year run (more or less)...digital audio on film is only in its 17th year or so.

Steve

Posted by Mike Schindler (Member # 1309) on 12-09-2009, 12:14 PM:

Can someone explain exactly what ghostbusting does? I understands that it cuts down on ghosting, but how does it do that? And why is it preferable not to use it when possible?

Posted by Julio Roberto (Member # 4976) on 12-09-2009, 04:53 PM:

In short: "ghostbusting" is the name of a technique that analyzes the pixels in a frame pair (two consecutive frames of the 48fps stream, each one representing the view from each one of the left and right eyes) and if it finds too much contrast in a pixel-pair corresponding to each image that overlap in the same point of the screen, it reduces the contrast usually by darkening the affected pixel(s) from one of the views.

You can think of it as a "smart, partial contrast reduction" function.

As a result, one of the views (from the eye pair, usually the left one), gets "distorted" with "spurious" dark(er)/bright(er) spots here-and-there.

So you don't wanna use the ghostbusting if you don't have to. But if your system produces too much ghosting, well, it's the lesser of two evils.

RealD zscreen does NOT have the sufficient polarizing performance to adequately produce a ghost-free image in a wide variety of situations, and thus, the "ghostbusting" is almost "mandatory".

Remember that studios are to stop producing ghost-busted versions of the films as the ghostbusting function is now being done on-the-fly by most servers out there automatically when you choose RealD as the 3D system in use (or activate it otherwise in the menu).

Posted by Jack Theakston (Member # 4484) on 12-09-2009, 05:09 PM:

quote: Steve Guttag
I dunno about that...what was the price of the 4-track mag system in the '50s? And what would that be in 2009 dollars?

According to a couple of breakdowns that I've seen from 1954, the going price was $1,500 for a set of penthouses and amps, which would be close to $12,000 today. Wiring and extra speakers could cost an extra $2,000.

Posted by Mike Schindler (Member # 1309) on 12-09-2009, 07:08 PM:

Thanks Julio.

Posted by Frank Angel (Member # 248) on 12-09-2009, 07:17 PM:

So if the ghostbusting processing is not DCI compliant, then is Disney going to stick to their statement that they won't book their product into theatres that don't have fully compilant DCI equipment and systems? So that means they will not be able to play their 3D content in RealD intalls?

Yah, that'll be the day.

Posted by Julio Roberto (Member # 4976) on 12-09-2009, 07:39 PM:

Not to mention the illumination levels of between 3.5fl and 5.5fl being used in all 3D systems that clearly goes against DCI 14/16fl REQUIRED levels ....

We all know what DCI is about.

A) Paranoid security at all cost (NOTE: make sure cost is passed to exhibitors)

B) More paranoid security at all cost (NOTE: make sure cost is passed to exhibitors)

C) Even more paranoid security at all cost (NOTE: make sure cost is passed to exhibitors)

D) Cost saving on "laser" print-outs, internegs, print quality testing, print replication, CRAP marking, transportation, warehousing, disposal, sound licensing, DTS disc printing etc. Making sure they get single format delivery, etc. (NOTE: move ghostbusting to post-processing, make sure exhibitor pays for it and try not to pay VPF's).

E) Exhibitor's control (NOTE: use KDM to know what, when, how, if someone is playing something on what screen at what time. Make sure the cost to deliver KDM's goes to the exhibitor, making them install many ADSL phone lines if necessary).

F) Make 3D prints available in digital only to force change due to competition in markets where 3-D exists in some places and not in others. (NOTE: Damm technicolor, damm you).

G) Who cares about quality. Spec 4K but say 2K is fine. Spec 4:4:4 12bits, but allow 4:2:2 10bits as well. Spec 14fl but allow 3.5fl as well. Spec resolution of so-many-pixels for "scope" and "flat" but allow less in non-triple flash 3D projectors. Spec XYZ colometry but allow Dolby to screw-it-up with color correction for Infitec filters (different on each eye) and RealD to change contrast with Ghostbusting. In short: make it look like the theatres need this very expensive high-quality projectors but deliver almost-the-same as a $1000 HD home one and even less than a current, inexpensive 35mm one ...

Posted by Mark Gulbrandsen (Member # 72) on 12-09-2009, 09:00 PM:

A set of DP-70s in the mid 1960s was about $6500.00. Now thats certainly alot of money in todays dollars....

Mark