4096x2160 full container... why bars?

[Kewl]

This screen is 16:9 (1.78:1). On the projector, we have three zoom presets: 1.78, 1.85, 2.39. The one we see is 1.85.

When we have 1.78 (or smaller) content, the 1.78 zoom preset will fill the screen vertically: the top and bottom green lines will align with the top and bottom of the screen.

So nothing is distorted, there just more black padding projected on the velour habillage.

IMG_5812.jpeg

IMG_5813.jpeg

[C. Pres Alliance]

Hmm. Well, let me try again, as I see why this question may confuse.

I don't care if the (black) container on the sides of my image gets lopped off. Indeed, that's what I would want: a zoom which fits my 4096x2160 master, as delivered to me, into the (evident) appropriate DCP Flat container spec of 3996x2160... without stretching my image to fit, which is a distortion of the intent/the restoration of the film. What I am getting, no matter how I try, is the image either slightly windowboxed in that 2160 vertical, or stretched to match it. That's the problem.

I'm sure this won't be an issue when I have deliveries of ProRes which do not exceed 3996 horizontal. I can start requesting them moving forward. But for now, I've got a heap of finished products which were delivered in what the lab has long considered the 4K spec of 4096 horizontal. And I don't want a "stretch to fit". I want a "fit", like I can do in pretty much any other finishing software that isn't outputting a DCP. If that's a zoom, so be it – but DCP-o-matic doesn't seem to do that, no matter what I try. Can it be done?

[carl]

Aha right - I think in that case what you want is to set the left and right crop in DCP-o-matic so that it removes the black bars on the side of your image. Then you'll be left with a 1.85:1 image, at the right height, which will require no scale/crop/pad to fit into the 4K "flat" frame... can you try that?

I would also reiterate my suggestion that if your lab wants 4096x2160 DCPs you should consider giving them what they want, no matter what people like me say!

[C. Pres Alliance]

Aha right - I think in that case what you want is to set the left and right crop in DCP-o-matic so that it removes the black bars on the side of your image. Then you'll be left with a 1.85:1 image, at the right height, which will require no scale/crop/pad to fit into the 4K "flat" frame... can you try that?

I would also reiterate my suggestion that if your lab wants 4096x2160 DCPs you should consider giving them what they want, no matter what people like me say!

Yes, I would love to try this very thing... if I can be instructed how to do it! Everything I have attempted results in a slight vertical stretch of the image. Help?

And just to clarify: it is the lab which sends me 4096x2160 for theatrical 4K. Not the other way around. Both labs I deal with are used to sending me files in this container. I, in turn, take that ProRes and create a variety of files... one for DCP, one for online use (which is either UHD or HD size), etc. I work with three different labs for scanning and color grading.

One good thing moving forward is that I now know to output my own 4K ProRes at 3996x2160 – when I am in a position to generate the final ProRes, myself. That's maybe half the time in my workflow; the other half of the time, I am getting it from partner labs.

[carl]

Can you attach or send (carl@dcpomatic.com) a single frame which demonstrates the sort of content you are dealing with?

[C. Pres Alliance]

I think I may have finally figured out the (obvious?) solution. I'm cropping the content in the DCP stats window by 50 pixels on left and right, which effectively "zooms" the window to fit the 3996 container and eliminates the slight top and bottom padding. I presume I am doing this correctly! (Rescaling "to fit DCP" is what erroneously results in the vertical stretch I don't want.)

If anyone has further instructions for this dummy as to how to accomplish this, I'm all ears, but I think I have figured it out.

[Carsten]

I guess it would help if we'd see a single frame of your source. The whole scaling GUI was very different in versions preceeding 2.15. We think it works much better now, but it may look odd at first.

[Kewl]

I'm cropping the content in the DCP stats window by 50 pixels on left and right, which effectively "zooms" the window to fit the 3996 container and eliminates the slight top and bottom padding. I presume I am doing this correctly!

Yes!