One of the most revolutionary changes brought by DCP has been the possibility of making copies without complications and at a very low cost. The change compared to 35 mm has been impressive; a single celluloid print could cost over €400 on average. For standard festival distribution, at least 5 copies were needed.
Now everything is much easier. Despite this, I still encounter directors and producers who only have one or two DCP copies.
In this post, I describe the process I use to make copies based on my personal experience, which has worked very well for me. The DCP copies I usually make are for festival distribution and screenings in alternative venues, without KDM (the keys used by major distributors to prevent unauthorized copying).
In the case of copies intended for commercial theater screenings, the process would be more complicated.
#1 Before starting: What is a DCP?
These are two links where it is explained very well: https://es.wikipedia.org/wiki/Digital_Cinema_Package and https://www.709mediaroom.com/los-paquetes-de-cine-digital-dci-y-los-dcps-parte-i/.
For more technical information, this is the DCI website, which establishes the DCP standards: http://www.dcimovies.com/.
In the process of making copies, what we need to know is that a DCP consists of a group of files stored in a folder—it’s that simple. These files are in .xml format (programming files) and .mxf format (audio and video).
Structure of a DCP without subtitles with the different files that compose it:
In this other DCP, a subtitle track is included. Inside the subfolder are the subtitles in .xml and the font:
These files are stored in a root folder, named according to the DCI standard.
#2 Prepare the hard drive
Now we are going to prepare the hard drive or flash drive where the new DCP copy will be saved. Here it gets a bit complicated, but not much.
The DCI standard establishes that hard drives for a DCP must be formatted in Linux format, in ext3. This did not pose any problem for me; when I started working with DCP, I had been using Ubuntu Linux for years. Starting to format hard drives in ext3 with GParted was a very simple process.
If you use Linux, you will know exactly how to do it; for Windows, there are programs like Partition Tool.
To format a hard drive in ext3, there is an important detail you should know. In Linux, administrative privileges are not created by default. This means that to access the newly formatted hard drive, you must do so as an administrator (sudo).
The other option is to grant write privileges to the drive to be able to make copies without issues; this is the command:
sudo chmod 7777 ‘hard-drive-path’ -R
During the first few years of making DCP copies, I always used ext3, according to the DCI standard. The problem is that it usually takes a long time to format and occupies between 2 and 3 GB on the disk.
For all these reasons, I started formatting in NTFS (from Linux), the native Windows format which is much more widespread.
99% of DCP servers run on Linux, which is why the DCI regulations require the use of ext3. But—and here is the trick—Linux reads most disk formats by default, including NTFS, so for several years now, we have always formatted the disks in NTFS.
Format purists will say this is incorrect. We have copied hundreds of DCPs to send to festivals and there has never been a problem. It truly simplifies the copying process significantly.
#3 Make the copy
On one hand, you have the hard drive formatted in NTFS (or ext3) and empty (without other files on the same disk), and on the other, the DCP delivered and reviewed by the laboratory. Now you know that if the original hard drive is in ext3, you will need Linux or a specific program in Windows to open it.
Making the copy is as simple as copying the DCP folder and pasting it onto the destination hard drive.
If you work in Windows, you must be careful not to copy hidden files, as they can cause problems when the “ingest” is performed on the projector. Hidden files are very common on Mac, so it is not advisable to use it for making DCP copies.
For copies, I always advise using Linux. Having a computer with any distribution has no cost and it is a much safer environment, without viruses or hidden files.
You really can make copies of your film easily, both as a backup and to send to festivals. Certainly, the prices of some laboratories are not justified, nor are “special” disks needed to have copies; any hard drive (preferably with USB 3.0) formatted correctly is valid for holding a DCP copy.