Film-Tech Forum ARCHIVE: Hotel Transylvania Screen SizeTrouble

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Posted by Lee Eady (Member # 6411) on 01-03-2013, 09:27 AM:

HI All, We are running "HOTEL T" at our 2nd run the past couple wks and we'll probly til they release it at Wallyworld.
anyway, we run it in 2D then 3D then 2D then 3D then 2D.
Its a FLAT movie btw. Being run on a Christie CB2000 SB with the Dolby show store & show player. the lens isnt mechanized, it has stickers for flat and scope that you line up to switch between the two. I like the 35mm changeover better personally- dont see why digital projectors couldnt just have two lenses that change back and forth likke the 35s...
The 2D looks great, it fills the screen and i see no probs.
When the 3D version plays, however, the image gets smaller (looks like 35mm flat) but its obvious that its uspposed to be as big as the 2D image- the tops of heads are cut off and a few scenes witth subtitles cut off half the words.
Weve only had these digital projectrs a few months now annd I havent quite gotn the hang yet. Ive been here 7 yrs with 10 35mm screens and now 4 of em are digital- some sort of 'test' is what they say- to see how digital will fit at 2nd run houses? Im sure the solution is simple. thanks!

Posted by Frank Cox (Member # 6258) on 01-03-2013, 12:47 PM:

I thought that DCI digital projectors were required to have automatic lens changer doodads.

My Christie 2210 has an auxiliary lens for scope that just drives itself over on a little track whenever I'm playing scope content, and drives itself back out to the side of the projector when playing flat. There's really nothing to do for changing formats other than make sure that the right cue is included in the playlist.

Posted by Darryl Spicer (Member # 711) on 01-03-2013, 01:16 PM:

Is this the first flat feature that you are running in 3-D for this projector?

It sounds to me like either when the projector was set up the installers failed to set up the masking for that format.

The format may be running in 1920 X 1080 causing the image to crop instead of running in 1998 X 1080.

It seems like there was also a requirement to zoom the picture for that model of projector. When we had that type of projector we had marks on the manual zoom lens for running in 3-D both Flat & Scope using the same mark and running 2-D both Flat & Scope using the same marks. Now in our case we were using a top masking screen so if it is side masking that you use there may be some differances involved in the lens set up.

So what could be going on is two problems. The format is running in 1920 X 1080 and the zoom is incorrect. For top masking we had to zoom the picture out to make it bigger and this also reqired a manual lens shift up or down to fill the screen. For side masking I think you still need to zooom the image to make it bigger to fill the screen but you do not have to lens shift. I think there is two problems here...the format may need to be set to 1998 X 1080 to eliminate the cropping and the lens zoomed for flat 3-D.

Posted by Dave Macaulay (Member # 813) on 01-03-2013, 01:40 PM:

I would put up the framing test pattern (from the touchscreen) and see what the installer did. You should see almost all the image inside the 1998x1080 "flat" frame line. Usually the line's a bit outside the screen area with a bit of electronic masking applied to hide keystoning. You will have to also select a "no crop" screen file to see the whole image. When you call up the projector channel again, it will go back to the usual screen file setting and remove the pattern.
You may be able to adjust the lens to have the image properly sized and centred on the screen, then create a new screen file to suit. You could then mark the lens and save the new screen file and select it in your 3D flat channel - this is a bit complicated but not really difficult.
Or call your service company and have them fix this. Something is definitely not right!
Since Christie charges a fair buck for the motorized lens mount some theatres don't have them, and some installers do a really bad job of setting the system up - in an attempt to avoid the usually unavoidable (if it's done right) manual lens adjustment between flat and scope. Only cinemas with side plus top and bottom movable masking (rare) can really get away without moving the lens between formats. The scope image (without lens adjustment) is quite a bit "shorter" than the flat image, and just a little bit "wider". You can get away with just top and bottom movable masking and mask off the extra image width in scope (25 pixels each side) but it isn't "digital done right".
It sometimes happens that the screen size is not actually 1.85:1 or 2.35:1 and the digital installer chooses to crop whichever dimension is short and fill the screen, losing image in the process. So instead of having letterboxed full-image scope on screen or pillarboxed flat, they fill the screen and mask off the extra image. Correcting the masking would be the right approach but that's often not possible - the owner wants the biggest image possible, filling the whole screen area. Some installers use image scaling (forbidden under the DCI specs) to adjust the image size to fit the screen: this reduces the image resolution and introduces unpleasant visible scaling artifacts.

Posted by Steve Guttag (Member # 268) on 01-05-2013, 07:34 PM:

The CP2000-SB, being a series 1 projector may have an EFIB board and thus can not play full 2K images at triple flash. Only the "-04" version has the FFIB board for full-frame triple flash.

If you have an EFIB board...then the only way you are going to get a full image is to switch your flash rate to 4:2 and deal with the flicker (like film...same flash rate of 48/eye).

Once upon a time there were 1920 versions and one could set up the input files for them and one indeed had to zoom out for the 1920 versions.

As to motorized lenses...it is possible to upgrade to a motorized lens mount. Some CP2000-SBs had a motorizable lens mount, some didn't. So you may need to update the lens mount and THEN add motors to your lens. Check with your Christie dealer/rep as for the best upgrade path, if you are interested.

Posted by Lee Eady (Member # 6411) on 01-08-2013, 10:30 AM:

THANKS TO ALL. Whichever solution works-and Im SURE one will... the correct answer gets a free pass to the Carmike $1.50 Movies in Bham, AL ($3.00 for 3D) and I'll even throw in a free SMALL popcoern! HOW DID YOU GUYSS LEARN ALL THIS?!?!? I've been up in this booth 7 years (digitals came in 3-4 mo ago but we are still mostly 35mm at a 6 to 4 ratio) but every time my tech comes and shows me something Im like "MY GOD! HOW COULD NOBODY HAVE SHOWN ME THAT!?" I feel like im climbing out of the topless pit- no thats not right, sounds like a bar- well i feel like im running in slow motion in a zombie dream and never can ctach up! and I still havent been properly trained in 35! AFTER 7 YEARS! EXPLETIVE!!!!!!!!!!!!!!!!!!!!!