Picture throw is off in a Flat DCP

[BrainFreeze]

Hi all,

I'm wondering if this has come up for anyone else before.

Our DCP just tested in a cineplex and the throw of the image was off by about 60cm (2ft) along the vertical - basically it would need to be "lowered" in order to sit correctly on the screen. We just left it there for the test, but clearly we need to resolve this.

The source is a 1920x1080 project
The DCP was exported at 1998x1080 (Flat)
The Doremi system at the cineplex had two options for playback - Flat and Scope.
We played back at Flat and had the problem described above. We switched to scope and of course that cropped the top and bottom.
The cineplex didn't have a playback option of "Full" although I can export to 2048x1080 Full.

I'm thinking the solution is to export at 2048x1080 Full and ask them to play the film back at Flat but I have no idea if will solve the problem. It just seems like the only other option.

Does anyone has any wisdom they could share about this subject?

Thanks,

Roland

[Carsten]

I have no idea what could have caused this. If you create a 1920*1080 in a flat container, with the default 16:9 scaling applied, it will sit where it needs to sit, with narrow black bars ('pillarboxed') on both sides. Playing it in flat should give the proper result. I can only assume they screwed something at this cinema. Putting it into a full container will not solve the problem. Unless only their flat setting is screwed and they'd had a special setting for full container (which is very very unlikely). Is this a 24 or 25fps project?

Make sure you have 'Scale to' set at 16:9, no cropping, and container set to 'Flat'. DCP-o-matics preview will display exactly how the DCI projector will project the file. Yes, there will usually be some very few pixels chopped off in the masking or under very bad geometrical conditions. There are also 'official' framing charts available, a DCI server/cinema SHOULD have one or a few on it's hard drive to verify the projector setting. If the cinema shows disney features, a framing chart will usually come with every feature on the hard drive. Maybe they will not believe YOUR DCP, but they should believe an official framing chart. Sometimes projectors are set up with relatively large crop areas to accommodate for a strange screen/auditorium shape.
Or, unexperienced staff screwed it up. With main stream content (and main stream audience ), this could go on unnoticed for a surprisingly long time. Sometimes a powercycle will cure the issue.

How much is that 60cm compared to the full screen height? 10%? 5%?

- Carsten

[carl]

Are we talking about an unwanted crop of the picture in Flat? Roughly what proportion of the screen height is the 2ft?

It may be worth you running a test-card in that screen to see if there's something funny going on with the setup. Carsten can probably suggest where to download a good one ...

[Carsten]

I will supply two charts via google drive.

Unfortunately, freedcp has gone...

It's easy to setup your own chart, but then again, they could question it. An 'official one' should be more convincing.

I heard ISDCF is working on a set of free charts.

- Carsten

[BrainFreeze]

Hi Carsten and Carl,

Thank you so much for your responses and sorry for my delay. I didn't have this conversation set to notify me if responses came in - fixed.

We've done a second test and the same problem is happening. In this second test the DCP was exported at Full 2048x1080. The cinema can only play it back at Flat or Scope. So we've tested a Flat export and a Full export with the same results - the picture is too high and falling off the screen at the top.

I'm attaching two pictures which demonstrate the offset. One is a photo from inside the cinema yesterday showing how the picture is going off the top of the screen. The other is the same frame, taken from the film itself, with coloured bars to indicate the amount bleeding off the screen (red) and cropping (green). I don't mind the cropping. It's the bleeding off the top that is a concern.

I have no idea what to do next. Nobody I'm working with has ever seen this before, including the manager at the cineplex.

Carsten, what are these charts? Are they calibration charts that the Cineplex could use to reposition their projectors? I've asked them about when they last calibrated their projectors and they tell me they do it frequently.

Any further thoughts and advice on this would be very much appreciated.

Thanks,

Roland

[BrainFreeze]

I see the test cards now, thank you for sending me these!

I will make sure to run them before the next test next week.

Is there any use in setting the container to 16:9 ?? I am curious how a projector would interpret this... I assume it would just disregard the container and play back as Flat?

I really am appreciative of all the help with this problem!

[BrainFreeze]

The problem has been solved.

Despite their assurances, the cinema had failed to re-positioned the lens to display Flat in the two theaters we tested it in during two different test sessions. The rooms they used were usually used for Scope so they weren't used to having to re-position the lens manually. Two weeks of redos and investigations that I'll never get back.

Thank you again to Carsten and Carl - you are a great help and I'm so thankful to this board for being here.

[Carsten]

Hi Roland,

what country is this taking place in? Quite peculiar they do not mind having unusable flat presets. I understand that some cinemas use fixed lenses because they have a fixed flat setting and then just frame-in scope. But even they need the flat being setup properly. I never heard of a screen being set up for scope only. You always learn something new...

Did they really fix this by adjusting their lenses 'manually', that is, by hand, or, readjust electronically?

- Carsten

[BrainFreeze]

The screening tests were being done in Canada, at a large commercial cineplex in a suburb outside of Toronto.

We used to deal with a really knowledgeable projectionist there, but ever since she left, we have had interactions with her two replacements that have not inspired confidence. With this test, the same projectionist tried two different theatres within the cineplex. He set the system to Flat but apparently was not aware that the lenses in those two theatres were not "smart lenses" and that he had to manually adjust the lens after switching the system. It's an electronic adjustment, not literally manual, by hand. His co-worker got wind of the fact that we were having this problem, (two weeks after they began) walked in and flipped the adjustment switch. Here's what she sent me afterwards:

"The projector is set up to play scope films because the majority of films these days are released in that format. We do get the odd in Flat (Transformers for example) and in that case I'll adjust the lens to the flat aspect ratio for the duration of that film's run. No issues with your film, it's just that the majority of the big studio filmmakers for these types of movies that we play go with scope."

So apparently this cinema is running with a projectionist who doesn't know that you have to reposition the lens for flat films. I have done an incredible job remaining polite while dealing with them, but to others involved, I let them know how outrageous this is.

We won't test there again.

[Carsten]

While I would be pissed off just like you for what happened there - we are a small single screen cinema, operating on a voluntary basis.
I understand how my personal career lead me here, and I understand why I know what I know. However, it has become very difficult to find people with the right attitude to learn and understand presentation tech and style. One reason may be that nowadays cinemas do not hire projectionists any more. They hire 'staff'. Some of them get told how to switch on and off things.

That said, I know many experienced and knowledgeable projectionists. Some with only a digital background, some who transferred nicely from the 35mm era. I don't know how you become a 'dedicated' projectionist nowadays. And I sure don't know how you find these people when you need them.
The projectionist job doesn't have much of a profile nowadays, and cinema operators do not want to assign a special status to them, maybe that's why young people are not attracted anymore.

All schools nearby offer voluntary courses for presentation tech (PA, theater, stage lighting, etc.), basically so they can support the schools own events. And there is usually a crowd attached to these courses. But around here, none of them is attached to AV or film presentation.

At our cinema, we have 6-7 people able to operate the projection and sound equipment for our daily showings. However, I am the only one being able to solve an issue like the one you had. Maybe that's the problem. Maybe I should go on a very long holiday so they HAVE to learn something.

- Carsten