Create DCP to portable disk or removable CRU?

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KrisSP
Posts: 19
Joined: Tue Aug 01, 2017 8:49 am

Create DCP to portable disk or removable CRU?

Post by KrisSP »

Hi all,

I have a computer set up to create DCPs (a HP z600). For practical reasons I need to have it at the office, not in the cinema.

I am looking for a faster way to create DCPs to a portable disk. In my experience (and as I've since read here), it's unreliable (and slow) to create the DCP directly to a portable USB drive. At the same time, creating the DCP, hen copying it, also takes ages, as the computer only has USB 2.0.

What is the best way to create the DCP to a portable drive I can bring to the cinema? Could I mount a removable drive enclosure, like this HP DX115?

Will it then basically be as reliable as an internal hard drive, yet portable?
Carsten
Posts: 2663
Joined: Tue Apr 15, 2014 9:11 pm
Location: Germany

Re: Create DCP to portable disk or removable CRU?

Post by Carsten »

Wether writing directly to a USB drive is actually slow or unreliable needs to be tested for the individual drive and computer. The typical encoding speed on a z600 is still slower than typical write throughput, even with USB2.0. I did quite a few tests with different media for source footage and target DCP, and the only significant difference I noticed was with image series as source footage (huge files), which should go on SSDs if possible. And of course, avoid immediate writing to USB sticks.


That said, I do have a CRU slot installed in my z600. I also added a cheap NEC USB3.0 card. The latter never turned out as reliable as SATA or the internal USB2.0, so, I am glad I have the CRU frame.

The SATA connected CRU slot (6602-6500-0500) is quite expensive though. You may as well use a CRU move dock (you may already have one at the cinema). The older USB2 movedocks also have an eSATA port, which works nicely with the Z600 internal SATA ports. You can bring them out through a suitable cheap SATA->eSATA slot connector, and configure them to eSATA (= hot pluggable) in the z600 bios. Depending on your DCI servers connectivity, a CRU drive may be the faster option for ingest, e.g. if, aside from a CRU slot, your server offers only USB2.0.

Sometimes you get CRU stuff second hand on ebay. With the move towards broadband distribution, it seems CRU has reduced it's CRU product line, and prices went up as well. I don't think the major mass duplicators continue to buy larger quantities.


In general, It's not a bad idea to have DOM create the DCP directly on the ingest drive, as the hashing process will then run on the actual ingest media, so it minimizes the risc of file corruption. A small disadvantage is that your project directory structure remains on the ingest drive. Some DCI servers may choke on them or need longer to mount the drive/see the DCP. Never had these issues myself, though.



- Carsten
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