Tag Archives: color

Next VFX/PDX Meeting: Monday, February 11th


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Time to mark your calendars yet again, good Portland VFX’ers.  The winter meeting is shaping up to be a veritable pixel bonfire!

Bent Image Lab’s go-to colorist Jalal Jemison is teaming with Blackmagic Design to show us the ins and outs of DaVinci Resolve, which has a great track record and, with it’s most recent release, is fast becoming the gold standard for color grading.   We’ll have the Blackmagic team on hand and the full tri-panel Blackmagic Control Surface in front of Jalal.  He’ll load us up with plenty of eye-popping before & afters from Bent’s recent work, and then show us step by step exactly how he gets those images to pop.  Usually his hands are a blur as he dials in the precise color values across the trackballs, but using the miracle of slow motion photography and instant replay, we may actually be able to make sense of what he’s doing!  The tricks up his sleeves that he usually reserves for clients.   Be careful, you just might learn something about the black art of color correction and image sweetening before he’s done.

But that’s not all.  This is a full on double bill and we’re equally excited to also have Hive-FX’s Lead Compositor James Chick presenting.  2012 was a big year for the Hivers and the momentum continues to build, as they pound out amazing work with their AE/Maya/C4D pipeline.  James has especially formidable on-the-box skills when it comes to After Effects, and has been carving a name out for himself as a prolific and gifted filmmaker.  To top it all off, Hive-FX has been building up it’s sister company Pinata Post and offers – yep, you guessed it – a fully functional DaVinci Resolve suite.  And now we’ve come full circle.  As Hannibal from the A-Team once said, “I love it when a plan comes together.”

Between James and Jalal, this is a can’t miss meeting!

As if that wasn’t enough – J. Bills will also be showing a brief demo of the newly released roto & paint powerhouse Silhouette v5.0.   You thought they’d done about everything there is to do when it came to speeding up labor intensive paint & roto tasks?  v5 brings a gigantic list of new features, including Mocha tracking integration, a warper, and a full suite of stereo conversion tools.  We’ll run through the highlights at the start of the meeting and get everyone up to speed.

Happy to announce that following the meeting, we’ll have a raffle with some big prizes worth $$$ thousands, including a license of DaVinci Resolve, a license of Silhouette v5, as well as a $500 credit from Artbeats Stock Footage, and some great books & door prizes from other sponsors.  Speaking of, special thanks to Autodesk and 3DPDX for covering our winter meeting costs.  Our meetings are always free, but the raffle will help raise some funds to cover costs for our upcoming spring meeting featuring presentations from ILM and LAIKA.  Big plans!

Meeting details – save the date!

Monday February 11th, 2013

7:00pm to 9:00pm

Clinton St. Theater

2522 SE Clinton St.

Hope to see you all there!

Eat Your Greens


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…and your reds and your blues too .  Thank you very much, Portland Farmer’s Market!

As digital artists, color is something we deal with every day.  You can bank on that when you walk in the door each morning.  There will be color!  Yet few take the time to understand how the color pipeline works in our VFX tools.

Mostly because the science behind it has historically been hard to digest.  Like broccoli.  What, you don’t like peas?  Digesting how a pixel gets from VFX software to your eyeball is going to take a lot of graphs and pie charts.  Mmmm, pie!  Now that’s something worth digesting.  Brussel sprouts?  Not so much.  But they’re good for you, and you gotta occasionally gag them down.

Luckily for us, genius-type Jeremy Selan (the Godfather of Katana over at Sony Imageworks) has picked up the torch from Steve Wright and made things more towards pie rather than sprouts.  Yes, Steve “The Guy Who Wrote the Book I Throw at My Comp Class and Jr Compositor’s Heads And Hope it Knocks Some Sense Into Them” Wright.  Or maybe just Steve “The Blue Book Guy” Wright is easier to digest?   …and this is all about easy digestion today as opposed to concussions.  But what this isn’t about is Steve.  Still a must read, his book did a very good thing and explained part of the puzzle, which is kind of the “how a pixel becomes law” approach to end to end gamma down the chain.

Jeremy raises the bid so much I think he just went all in, Texas Hold ‘Em style.  He’s just unleashed a white paper called Cinematic Color:  From Your Monitor to the Big Screen that is pure, unadulterated, Grade A certified gold.  Nah…  platinum.  It doesn’t get any better than this.

Obscure bits like CIE colorspace – that of your own human eyeballs?

In there.

Linear workflow?  Covering both display-linear and scene-linear?


Macbeth charts?  Marcie?  3D Color Polyhedrons?

Oh yeah.  And more.

Ah Marcie, makin’ hair highlights look good (since 1994)

Sure, it’s both dorky AND nerdy.  I’d darn near call it nerky!  But it also accounts for why things occasionally look right or wrong on your screen, and is an essential step in tracking gremlins down when things get messy and color nodes and lighting tools stop doing what you expect them to.

This is the de facto color pipeline document to end all color pipeline documents, fully vetted by the VES brain trust and free for mass consumption.  Pick yourself up a copy and more info here.

And 1000 thank yous to Jeremy for putting this together and putting years of research and expertise out there.  Hats off to ya.  By the way, nice black and white website.  🙂

An accidental late night sexy text to DPX


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So everyone gets what VFX is.  And PDX is a no brainer for anyone who’s ever gotten tired of writing out P-O-R-T-L-A-N-D and is fine enough with an airport acronym, and a cool one at that (what with it’s iconic X).  But DPX?  Who the what now?  Have I gone and scrambled my brains at the Driftwood Room again prior to posting?

DPX is my favorite file image format.  And oh how I missed it.

You’ll have to excuse me for a sec while I geek out.  But we’re never gonna survive unless we get a little geeky.

Pulling a DPX into Nuke used to mean you were working on a film.  Hell yeah.  This is something I took for granted; that those tasty dpx’s would always be sitting there, waiting for me every morning.

I’m not sure quite sure when they went away, but at some point along the way, along came EXR’s, and things got all complicated.

Now at my brand new gig, I’m the “end of the line.”  Has a nice ring to it!  And guess what?  DPX is back in vogue.  Allow me to sing it’s praises.

For live action footage, there is no better.  Nuke absolutely eats a DPX for breakfast.

And I’m not talking Portland brunch…   where you cruise into Tin Shed on Alberta, put your name down, grab yourself a cuppa the “free” Joe only it’s not really free because you’ll be billed for it in the event that you wait long enough to finally sit down and your server sees that you have the cup and marks you down for 1 stumptown special, but let’s not even go there yet because you’re still sitting there waiting but you stick it out because it’s like you brought your dog and Tin Shed is like the only place that really allows dogs because they have the outdoor seating and all that but it’s like sunny and so it’s crowded but hey it is SUNday after all so like whatever I’ll just sit here for what time is it? is that even morning anymore?  and wait until they call my name and there’s not really much else within biking distance except hey maybe Juniors is my backup plan but I’d have to tie the dog up out front and the food is good and all but it was kind of dirty in there last time I was there or at least my cup had spots on it and my water was kind of, I don’t know, dusty?  so like I should probably just wait it out but there’s like 3 other 2-tops ahead of me on the list, like when did this place turn into Gravy anyway I thought Tin Shed was like normal but whatever it is like the best thing Alberta has so I better just suck it up.

Ok, that diatribe you just went through?  That was an EXR.  DPX would have you out the door and smiling already while EXR is still loading in scanlines.  If you want to talk in brunch terms, this is like Gravy vs. Equinox – am I right?  Ok, maybe I should explain that ref for any non P-towners who aren’t familiar with our obsessive brunch scene.  Gravy over on Mississippi Ave is hands down one of the best brunches in town.  The best french toast in the city – maybe the galaxy.  But you wait for it.  It’s a mob scene even on a weekday.  In other words, it’s great but it’s the SLOW boat.  However, right around the corner from Gravy is Equinox.  Which is a damn good brunch – up on par with Gravy for sure.  The difference being it’s tucked around the corner, just enough off the beaten path where you can walk right in and sit down immediately.  You’re done and moving on with the rest of your day while the Gravy folks are still standing outside, tapping feet, shooting glances to watches, pondering how much longer before they just…  bail.

Don’t be afraid to bail on EXR when the circumstances permit.  Proof?  You want proof?  Get this – for a plain Jane little 3 node comp render of 50 some odd frames in Nuke (in > blur > out) with footage shot originally with a RED  Epic @ 4k,  here are the stats:

EXR (zip scanline) – 2 minutes 57 seconds

DPX – 10 seconds.

No @$#% kidding.  10 seconds.  I mean, I had a feeling DPX would be faster, just from working with them time and time again…   but I’ll admit that had my head spinning.  I’m not even sure how to explain this because it doesn’t add up – there is nothing apparently different about this machine I’m on…  there’s no DPX equivalent of a Red Rocket card or anything, and no GPU accelerated nodes in my script.  I’m scratching my head – how is this possible?  This box does have an SSD but I was sure to clear the caches before rendering, so it should be apples to apples.  I ran it twice and got similar render times.  The sys admin wizards at Weta Digital might have some sort of caching enabled on Linux here that is somehow locally stashing the DPXs in RAM, but not the EXRs.  Hmmm.  That gives me more questions than answers!  Mental note:  never ever leave Linux.

Anyway, a 2nd opinion is in order, good doctor.  Let’s try something a bit more scientific and I’ll shoot this to the renderfarm.  I’ve switched shots and have a 2k shot that originated on film, not that it really matters once you’ve made a DPX and an EXR.  Kicking these off now and will wait for that juicy stats email…  looking for total time elapsed and I’ll get you a per frame CPU time (minus batch load time).

EXR (piz):  6m 53s – 7 secs

EXR (scanline): 6m 38s – 6 secs

DPX: 4m 10s – 4 secs

This was done on a Sunday – as low traffic and open of a farm as Weta Digital gets.  Different versions were rendered within minutes of each other, and those Nuke renders should have had the blades all to themselves.  The bottom line:  33% faster rendering.

You can talk all you want about how Nuke uses EXRs as it’s internal intermediary format and is floating point across the board.  Bla bla bla.  Look at the results.  That adds up to a heck of a lot of saved time over the course of the day, not to mention the interactive boost while working.  As long as your capture format is less than 16 bit, and if they are shooting digital (or even film), it is most definitely less than 16 bit – you simply cannot beat what I’ll call “integer love.”  The CPU just chews through it.  For grained live action footage shot with most cameras, DPX.  There is no substitute.

The RED Epic, with it’s claimed 11 stops of RAW dynamic range?  No problem.  The Canon 5D and it’s 14 bit sensor?  Easy money.  10bit Log DPX handles as much dynamic range as 16bit linear because, kind of like an mp3 still sounds damn good (or maybe FLAC is a better comparison), log space will put all of the image goodness where it counts.  Your highlights?  Don’t worry, they’re unscathed and intact.

File size you say?  Network traffic?  Also not a problem here.  10bit log DPX was 13mb per beautiful grainy frame in this example (2k live action plate).  EXR/Piz could only come up with 14mb.  That varies, but the time spent unpacking them doesn’t so often a small filesize advantage for Piz can be ignored in favor of performance.

Some people will scoff at a raw DPX and it’s log encoding, saying it looks washed out and unviewable.  First of all, who are these people and why are you letting them anywhere near a vfx pipe decision?  Amateurs!  Ha!  The truth is, an EXR in linear colorspace is just as strange to view in it’s dark raw state.  You’re never going to view either of them raw and are gonna have to chuck a LUT on it either way, so this is a non-issue.  Worry not, Photoshop can still open it correctly.

Don’t get me wrong, DPX is not for everything.  There’s the whole alpha channel thing.  The dpx spec can handle it (as well as rendering up to 16 bit linear) but many of the software, After Effects comes to mind, still seems to be stuck on the old Cineon spec.  Cineon was what DPX was before it was dpx – .cin – and Cineon had no alpha channel support and was locked to 10 bit log.

CG renders especially will use all of the extra range goodness that EXR can offer up.  Over in EXR land, Piz compressed is the way to go for live action plates over slow networks, or large feature film projects that need oodles of storage.  If you can afford larger filesizes, Nuke likes a good scanline zipped EXR much better.  Single scanlines for live action, and often shops will write tiled for CG out of the renderer and then convert to ZipS as a post process.

Really, the big revelation with EXR was embedding multiple passes into one file, and knocking things down to “half-float” for all of the calculation and storage advantages.  Finally, floating point was worth the price of admission.  Historically, Tiff could always do float precision but no one used it because the extra usable range came at such a rendering and disk space cost that it was overkill 99.997% of the time.  In fact, at Weta prior to the EXR revolution, we were using liff (essentially a log IFF) as our primary format for CG renders, for many of the same reasons that DPX works so well.

When EXR 2.0 is finally released, it will up the ante and you’re going to start seeing more standardization of the deep image formatting for CG without holdouts or layering problems that useless per pixel Z passes always had.

But for live action plates (in most cases*), viva la DPX!