REDRAW 2K FOOTAGE PROCESSING ON MAC PRO

[J. C. John]

Happy new year!
I would like to purchase a RED scarlet, before doing that I want to make sure that my computer specs will work with 2k REDRAW footage coming from the scarlet.
I'll be shooting on 2K because I own super16mm prime lenses that I used to shoot with my film camera. My macintosh pro specs are the following:
Davinci resolve 9.04, OS X10.8.2, 2.66 Quad-Core Intel Xenon early 2009, 14GB RAM, Nvidia GT120/GTX470 macvidcards combo, 2X512 SSD's,
HDlink3D SDI card, BM smart-view 17inch SDI monitor for reference. Do you think I could work 2K footage? How big is a REDRAW 2K frame?
Is there a link that I can download 2K RAW footage to color grade on Davinci and see how it handles playback and processing?

Regards
John

 

[Jeff Kilgroe]

The computer is OK and will handle 2K just fine. You're sacrificing RAM bandwidth by having 14GB installed as that is an odd-matched capacity, meaning not all of your modules are the same size. It will drop into dual channel or single channel access mode for the RAM. I would recommend more RAM - 24+ GB, but the system is now 4 years old so you have to decide if it's worth dumping more money into. It was already purchased with only one CPU rather than two, meaning your maximum RAM capacity and bandwidth is already cut in half from its potential, as well as only having 4 cores out of a possible 8. So yeah, it will work, but it's not going to be a speed demon by any means.

You no longer need the GT120 as a GUI card for Resolve as v9 uses CUDA off your primary display card. However, the hacked GTX4xx series can be finicky for use as a sole GPU in the systems. I think they're working fine under OSX 10.8, as do the GTX5xx series, so just something to keep in mind.

Using 16mm lenses, you may actually find it better to shoot 3K much of the time. It will give you pristine finish at 2K or 1080p and many of the lenses will still cover the 3K image area (or very close to it) at longer focal lengths. You will have lots of options to experiment with.

A 2K 16:9 frame is roughly 13.5MB when uncompressed into memory at 16bpc. Up to 18MB in size in RAM, depending on your application and whether it treats it as RGB or RGBA. 2K isn't that demanding in the grand scheme of it all, at 18MB RGBA, it takes roughly 2.5GB of RAM to cache a 5 second shot.

 

[J. C. John]

Hi Jeff, thanks for your detailed answer! My system goes up 16MB RAM. What I did was adding 3X4GB of RAM and left back a 2GB that was fitted on my mac from the beginning.
From what your saying It's better to remove the 2GB of RAM and have 12GB of RAM (same size modules) in order to achieve clearer channel path? Oh, one more Q. how much footage (in minutes) a 64GB REDMAC records on 2k?
Regards
John

 

[Jeff Kilgroe]

The memory architecture on the Mac Pro 3,1 -- when combined with a "Nehalem" core Xeon CPU -- provides single, double or triple channel operation. You will get the best performance from the RAM if you install 3 identical modules, it will run in triple-channel mode. If you install all 4 modules, you gain the extra capacity, but it drops to dual channel mode, once again providing all the modules are matched. You're operating in single-channel mode due to the mismatched module. When we talk in channels, that is how many channels or segments of RAM are being accessed simultaneously. It's not a linear performance gain as the terminology implies, but you should see nearly double the memory throughput by removing the odd 2GB module. Depending on what you're doing, but generally speaking in R3D workflow terms, I prefer to have 4GB RAM per core in workstations with extra overhead for OS, apps and even more if the system is to be used for a lot of compositing, FX or dealing with 4K and 5K shots regularly. I'm running 96GB RAM in my 2010 Mac Pro... My HP Z820 workstation has 256GB RAM... I find that 16GB RAM in my Macbook Pros (2011 model and 2012 retina model) is not enough and these are quad-core systems. I wish the retina model had a 32GB RAM option!

If your system is a Mac Pro 3,1 Nehalem quad-core, you will know because your RAM will be running at 1066MHz if it is, then it can actually handle 64GB RAM via 16GB DIMMs You would get the best performance out of your memory via 3 x 8GB or 3 x 16GB for a respective 24GB or 48GB total. Like I said above, it's an older system and I don't know how much you would want to dump into this. Honestly a new quad-core Mac Mini outperforms your Mac Pro in many ways, the new iMac trounces it. If you do decided to upgrade the RAM, you would do fine with 32GB, 48GB if you want to splurge a bit. You're going to run into plenty of other bottlenecks along the way, regardless of what you do to upgrade the RAM.

A 64GB REDMAG will hold about an hour of 2K when shot at 24fps and 5:1 compression. At 10:1 compression, you can get 2+ hours, but the compression really starts to show.

I realize you're talking about shooting 2K due to lenses you have, but you really may want to consider all options and possibilities here. You need to shoot 2.5K to 3K to get a proper 2K or 1080p finish here. The system is optimized to work best when shot at 4K (for Scarlet), 5K (for Epic).


You are also going to run into storage constraints rather quickly with only 2 x 512GB (roughly 480GB usable) for SSD storage. Once again, depends what you're working on and doing. But you will definitely need to add more drive space once you get going.

 

[J. C. John]

Once again, thanks for your time answering my questions with solid and helpful answers! I think I'll go with Scarlett's native resolution (4k) and shoot with my Nikon primes instead of the super16 lenses. So hopefully my system will handle the extra 2K as it is... I'll try to get some 4k test footage and have a look.
Kind regards
john