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Tips on Digital Cinema Theatre DCP test screenings

Before you check your DCP in a movie theatre, you need to know the specification of the movie theatre you are using.

Here are some question you could ask:
-Are the scope and flat presets without cropping?
35 mm cinemas often cropped much of the picture to mask the fact that the projector is tilted. Even with lens shift, some digital cinemas still has tilted projectors that need presets for scope and flat with cropping to fit the masking on the screen. This hides the fact that the shape of the picture often has a trapezoid shape. For a test screening of a DCP you could ask for a preset on the projector without cropping, this way you could watch for artifacts on the edges of the picture. You should also consider that the film will be shown in theatres with cropping, so you need to use safe zones. Also consider that a 1920×1080 DCP could reveal that the projector is tilted and the picture has a trapezoid shape, so scaling and cropping 1920×1080 material to 1998×1080 (Flat) when you make the DCP should be an option. If you want to watch the movie with better perceived contrast you should use the standard presets.

-Is the peak white luminance 14 Fl on the screen?
See this post for more info.

-How is the uniformity?
Old 3D screens can have bad uniformity.

-Is the sound correct?
See this post for more info.

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Tips on converting Film Festival programmes to the DCP (Digital Cinema Package) format.

This year I converted all films that was not 35 mm or DCPs at the Films from the North 2011 section at Tromsø International Film Festival 2011 to DCPs. In total I made 33 DCPs (about 10 hours) in two weeks. I was also responsible for screening the DCPs at the film festival. I checked the sound level on each DCP in the cinema theatre and wrote down what level they should be played back at. I also wrote down what audio preset should be used (5.1 or 2.0 with Pro Logic decoding). If you are converting to the DCP format for screenings where you will not be present I recommend using standard cinema level 5.1 sound mixes.

Here are some tips if you are thinking about converting a film festival programme to DCPs:

    I recommend using batch processesing when making DCPs of short films, I used Fraunhofer Easydcp + to make 1-5 DCPs each night.
    Have a tested worfklow before the festival films arrives. It must cover both interlaced and progressive material. Standard definition and high definition. Stereo and 5,1 sound. Material that has subtitles outside the safe zone and material that does not use a standard resolution. . .
    Use different quality control stages, I recommend two computer screens so you can look at the material fullscreen 1:1 . I recommend using the RGB parade scope in Apple Color/Resolve to check how the source is color corrected/graded. I recommend checking the DCPs in a movie theatre, preferably the screen you will screen the film at or one that is suited.
    Find out how much the picture is cropped at the theatre where the films are screened. Also check for a 1920×1080 1.77 preset.
    If using 25 fps or 30 fps DCPs, check if they work in the theatre that will be screening the films.
    If using DCPs with stereo sound make sure the theatre has Dolby Pro Logic 1 or 2 decoding or something similar to get the speech in the center channel. If a stereo soundtrack is played in stereo everyone on the right side of the screen will hear speech coming from the right and those one the left will hear it coming from the left.
    In total I made 33 DCPs (about 10 hours) in two weeks. I always had 1-5 DCPs being made each night that I tested the next day. I could convert 1,5 hours from one day to the next with easydcp + on a quad core computer. Some people uploaded their films as Prores quicktime to a FTP server or used Filemail Corporate instead of delivering on Digibeta or HDCam. This helped speed things up.
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Some ideas for best common practices when mastering DCPs

Before sending a hard drive with a DCP at least check the DCP with the free or full version of Fraunhofer Easydcp Player. That way you will see if the DCP fails the basic tests done by Easydcp player like “Check file hashes” and that the disk works and have the correct DCP on it. The Doremi and Sony (with recent firmware) accepts NTFS disks, otherwise, an ext2/ext3 Linux disk could be used.

If a movie uses a workflow like the movie Inception where there is no Digital Intermediate (DI) and the film is color timed photochemically in a film lab, the color timed print has to be scanned and fine tuned for 2.6 gamma 12 bit linear DCI P3/XYZ color space to make the DCP. Otherwise, the 35 mm print has to be screened. The offline edit or an SD videotape should not be used to make a DCP for theatrical distribution.

A DCP should be made from the DCDM with correct XYZ colorspace and 2.6 gamma made from the Digital Intermediate (DI) that has been graded on a DCI P3/XYZ color space projector with 14 foot-lambert of light. The DCP is normally made from the emulation of how the 35 mm print will look on a digital projector. This emulation (3D LUT) is baked into the DCDM. The resolution should be 2048×858 or 1998×1080.

A DCP could also be made from a file-based master in 10 or 12 bit, Rec. 709 HDTV colorspace graded on a HDTV monitor. The Director of Photography should approve of how this looks in the movie theatre because an HDTV monitor is not ideal because you don’t typically have 14 foot-lambert and a dark room when grading on an HDTV monitor. But the result you can get from a 10 bit HD master is good enough for films like The Social Network so it could be great when done correctly. The resolution should be 2048×858 or 1998×1080. If you grade the film in rec. 709, the movie could have less bright colors in the 35 mm version than in the DCP version.

The sound must be 5.1 (85 dB). If the theatre you will screen the DCP at accepts a stereo mixed DCP you could deliver that, but otherwise it has to be 5.1.

The Digital Cinema Naming Convention must be used to name the DCP.