Film-Tech Forum ARCHIVE: Crooked and masking issues in D-Cinema???

This is topic Crooked and masking issues in D-Cinema??? in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Michael Gonzalez (Member # 593) on 12-03-2008, 06:53 PM:

I took my brother to see "Quantum Of Solace" this past holiday weekend. We went to Cinema Hollywood in Burch Run Michigan. The movie was presented in D-Cinema but the picture was slightly crooked (really only noticeable during subtitles but still very annoying) and the picture was cut off a bit on the top and bottom (but no visable picture bleeding on the maskings). The picture otherwise looked normal so I do not believe that it was in the wrong "lens" but I dont understand how both these problems could exist.

I operated the Christie 2K before and when the technicians installed the projector, they set the pictures up in both Formats and then Locked them in place. Has anyone had these settings degrade over time where AccessIT has to come back and readjust?

Posted by David Zylstra (Member # 4230) on 12-03-2008, 11:38 PM:

I have not been able to get back up there to redo a "safe image" survey checking how much of each format is being cut off since they came through and added the WCL lenses, but the picture being cut off could be that the picture size and throw falls right at the limit of the zoom on the lens (and maybe it should have been changed).

Several auditoriums in Birch Run are still dual 35mm/digital and the digital is off center with a noticeable horizontal keystone - I'm guessing you were in one of these (and the installers level the picture to the top masking with minimal regard for keystoning).

I will be doing a brief stop in this week up there - if you let me know which auditorium you were I will give it a look and get the service tech in there if it is something that needs to be fixed.

Posted by Michael Gonzalez (Member # 593) on 12-04-2008, 07:11 PM:

Oh wow thanks for the info Dave. I didnt expect to hear from the actual tech. I asked for a manager and told her what the issues where and even went as far as to suggest calling their tech to take a look at it. I wont go as far as to say that she rolled her eyes at me but I got the impression that she was not taking me seriously. She made a show of telling her Booth Person to check on it even though he could have really done anything to fix it.

Anyway, I was in auditorun #6. The image was tilting counterclockwise slightly (my brother didnt even notice until I pointed it out during the end credits). The cutoff also wasnt too noticeable except when the MGM logo was on the screen, then it was obvious. Hope this info helps...

Posted by David Zylstra (Member # 4230) on 12-05-2008, 11:26 AM:

Yes, that helps! I'm not actually the tech, but part of my job is to manage our support contracts.

I was actually afraid you would say #6 . . . . . that is the one auditorium where the digital was put way too far off center and has an extreme horizontal keystone. That one is actually scheduled to be moved to the center port soon since we don't need the 35mm in that one any more and it is most likely our next 3D screen.

Do you work for the AMC in Holland? Back when they opened I was the head projectionist before I moved to Detroit.

Posted by Mark Gulbrandsen (Member # 72) on 12-05-2008, 08:58 PM:

You can correct at least some of it to make it less notacible with the lens shift on the lens mount... have had to do it numerous times and it works out pretty darn well. The thingis you may actually HAVE TO do it yourself... the install people don't have a clue!

Mark

Posted by Michael Gonzalez (Member # 593) on 12-06-2008, 07:57 PM:

quote:
the install people don't have a clue!

Nice. I know that before they left during the install, I came in early and ran trailer packages looking specifically for any issues. Two of them had that swirling color thing in the background (not sure what they did to fix that) but the rest where fine but boy did I ever get sick of seeing that damn Pirates of the Caribbean 2 trailer.

Posted by Joe Redifer (Member # 3) on 12-06-2008, 08:21 PM:

The only time I watched a movie in D-Cinema was at the Regal operated UA, ummmm, I can't even remember the name of the theater, but you can bet it is named after the mall (which was so generic that I can't even remember the name of it, something like Colorado Crossings or something boring). Anyway it was Nightmare Before Christmas and it was cutting off a significant portion of the top of the screen.

I was not impressed. Digital is supposed to be perfect.

Posted by Tristan Lane (Member # 1169) on 12-09-2008, 11:37 AM:

quote:
You can correct at least some of it to make it less notacible with the lens shift on the lens mount... have had to do it numerous times and it works out pretty darn well. The thingis you may actually HAVE TO do it yourself... the install people don't have a clue!

Lens shift is not reccommended in houses using a WCL. Since it is a fixed zoom lens, it will further shift the image between flat and scope. Unfortunately, the tradeoff with using the WCL is that keystoning is present. I believe this problem was present with the anamorph as well, but to a lesser degree.

Posted by Michael Gonzalez (Member # 593) on 12-10-2008, 04:32 PM:

Pardon my ignorance as it has been about 2 years since I operated these projectors but why did they switch to the WCL lenses if there are know issues with the images? Is it safe to guess that WCL has something to do with Digital 3D?

Digital cinema is advertise as a "perfect picture" everytime. How can an operator knowingly show a blatantly keystoned image to paying customers (rhetorical question)? David I don't personally blame you but obviously the problems in #6 was a known issue and I know that I would have definitely preferred to have watched the 35mm version as oppossed to a screwed up digital presentation.

Posted by Steve Guttag (Member # 268) on 12-10-2008, 06:05 PM:

The WCL is a fixed 1.26 magnifier (spherical). Being that it is mounted on a motorized arm, it can be programmed in as a channel so that when one selects "scope" in it comes. It has nothing to do with 3D. Its job is just to magnify everything.

Despite the claims of others, it is not as light efficient as an anamorphic lens or anywhere near it. If you have side only masking, an anamorphic is going to get you a more light efficient system. What the WCL brings to the table is a MUCH lower cost lens that is not going to screw around with the pixels in either the projector or the screen...no "scaling" is necessary with it.

It does require a little bit of a set up and Mark is right, with enough effort, you can get a very good Flat and Scope image, even with lens shift. Whom ever said you can't lens shift with the WCL is just plain wrong.

What lets you get away with it more is that Scope images only fill the imager in width and Flat images only fill the imager in height.

As such, you have wiggle room to move the image on the imager to get both Flat and Scope centered on screen and lens shift as well.

As for "perfect pictures" I guess some advertise them...the realities are that digital must obey the laws of physics too and when one is not dead center with custom lenses...there will be compromises. Digital should have every bit as much of a chance of delivering a low-keystone image as film. Like with film though, the installer can make all of the difference between just having a picture and having a great picture. And if the wrong prime lens (focal length) is being used, that isn't the fault of the process anymore than it would be if one had the wrong lens for film (and I've seen that happen too).

Steve

I've done it on a CP2000-ZX with pretty decent results.

Posted by Monte L Fullmer (Member # 2797) on 12-10-2008, 10:04 PM:

Can I bend this topic a bit since we're dealing with masking issues?

Let's say there is a cinema with a full 2.35/1 UNMASKED (common height) screen. Thus, when shooting 1.85/1 flat on this screen, the sides are unexposed.

Can this screen be used for D-Cinema being this common height screen, or does the screen have to be a common width screen?

thx-Monte

Posted by Kevin Fairchild (Member # 4985) on 12-11-2008, 01:39 AM:

quote: Monte L Fullmer
Let's say there is a cinema with a full 2.35/1 UNMASKED (common height) screen. Thus, when shooting 1.85/1 flat on this screen, the sides are unexposed.

Can this screen be used for D-Cinema being this common height screen, or does the screen have to be a common width screen?

Common height works with D-Cinema. At our theater we have fixed scope masking. When we project flat it is just centered on-screen. It looks pretty good since you can fix the keystone so that the sides are completely vertical.

Posted by Tristan Lane (Member # 1169) on 12-11-2008, 12:17 PM:

quote: Steve Guttag
Whom ever said you can't lens shift with the WCL is just plain wrong.

Wasnt' me. I said it was not reccommended, but I realize that statement isn't true either. You are limited by how much physical offset you can make up for on the imager, and there are going to be situations where keystoning will be present.
I still feel that that the WCL is a compromise simply to save money at the expense of light. It is far more forgiving that the anamorphic. As Mark stated, the installers may take advantage of this at the expense of the presentation.

quote: Kevin Fairchild
At our theater we have fixed scope masking

You don't have moveable masking there? The one accross the street from you does! [Wink]

Kevin, are you sure your masking isn't just broken? I doubt that a theater of that age would have been built without moveable masking.

Posted by Kevin Fairchild (Member # 4985) on 12-11-2008, 05:06 PM:

quote: Tristan Lane
You don't have moveable masking there? The one accross the street from you does! Kevin, are you sure your masking isn't just broken? I doubt that a theater of that age would have been built without moveable masking.

I think that you are confusing us with Carmike and Regal. My parents built a new theater in Pasco, across the river from Kennewick. I am 100% sure that we do not have moveable masking. Would I like it? Yes, but it wasn't my call. In all honesty, it truly doesn't look that bad since the sides of the flat picture are perfectly vertical with digital projection.

Posted by Tony Bandiera Jr (Member # 2365) on 12-11-2008, 05:55 PM:

Blah, blah, blah...another thread pointing out the SERIOUS shortcomings of D-Cinecrap.

Stick with film people, it's a lot less hassle. [Smile]

Posted by Monte L Fullmer (Member # 2797) on 12-11-2008, 07:00 PM:

quote: Tony Bandiera Jr
Stick with film people, it's a lot less hassle.

Oh, I definitely agree - if the invasion of "booth clowns" can be taught and paid accordingly to the skills required in running film as what the lot of us here know how...but, do pigs fly?

-Monte

Posted by Steve Guttag (Member # 268) on 12-11-2008, 07:21 PM:

Digital installations and projection and upkeep can, will and will continue to be neglected just as film. The question is, will digital be neglected less so?

Remember, John-Q-Public, by and large, watches 4:3 origination material S T R E T C H E D out on their new 16:9 monitors (and everywhere a 16:9 monitor is in a public space)...so they aint so picky to begin with. You could probably run everything full-screen in a cinema and they'd go for that too!

Steve

Posted by Monte L Fullmer (Member # 2797) on 12-11-2008, 08:52 PM:

quote: Steve Guttag
origination material S T R E T C H E D out on their new 16:9 monitors

Then, the definition of worse is when they watch a scope film STRETCHED out to a horrible 3.2/1 if they don't know how to set their resolutions right.

Posted by Mark Strube (Member # 4190) on 12-12-2008, 03:28 AM:

Monte... don't be silly. That's simply super super widescreen! Eat that Cinerama!

Posted by Monte L Fullmer (Member # 2797) on 12-12-2008, 03:38 AM:

Tell that to them WallyWorld clowns with their 84" demo plasmas in front of their stores playing "D.K." all stretched out since they "effed" up the display settings. [Big Grin]