Logarithmic Conversion in Nuke vs. After Effects

If you ever need to use the Cineon Converter effect in After Effects… you know, maybe you want to create a LUT adjustment layer to match your real comps… you might save yourself some time by remembering this:

Nuke’s default log2lin gamma of 0.6 is like 1.0 in After Effects.

This concludes my public service announcement.

My Shot on fxguide

Just found out about an article on fxguide about White House Down. It mentions a full-cg shot I’ve worked on for Scanline Munich. Scroll down to the pool splash shot, of which I had already posted some stills previously.

Also, check out Scanline’s breakdown of the Air Force One explosion at the end of the article!

I’m hotlinking the vid of my shot from fxguide here, don’t know how long that works though…

Comp-Fu Answers Part 2

Once again I’ve pulled out keywords from my piwik reports!

graphics to rec709 lut
— anonymous

“Graphics” can mean a dozen things. If you have designed some stuff in Photoshop or taken screenshots, for example, they are probably in sRGB. To convert it in Nuke for a rec709 project, just select sRGB in the read node. This will linearize it and if you put on the rec709 LUT you’ll see that it appears a bit darker than in Photoshop. In Fusion, you can convert the image using the Gamut tool (input sRGB, output ITU-B-R.709, both gamma checkboxes enabled).

in fusion for which reason there is no gamma slider??
— anonymous

That made me laugh. All I could think of is this meme 🙂

I guess you mean the nifty viewer controls that Nuke has? You need to add a viewer LUT for this manually. There’s the GainGamma Fuse that ships with Fusion or my gpu accelerated sRGB/rec709 LUTs.

nuke ramp tutorials
— anonymous

Oh come on. What’s next? A tutorial on how to prepare a peanut butter sandwich?!

how many lens flares in total recall
— anonymous

Well, I didn’t count them when I talked about the movie on my blog. But here’s somebody who did!

Comp-Fu Answers Part 1

Welcome to my new show where I answer questions that are based on google searches that brought users to my website. (disclaimer: I’m using piwik for web site statistics and search keywords are transmitted by the user’s browser. It’s anonymous though, so relax.)

what is color space and color temperature
— anonymous

Thanks for your question, Mr Anonymous. Color Space and Color Temperature can be looked up on Wikipedia. In VFX specifically, the term color space usually means the way that a color is being split into separate channels for digital processing. RGB by default (red, green and blue channels). It can be converted back and forth to spaces like HLS, Lab, YUV and so on where you still have red, green and blue channels but now each channel contains a different color attribute. In HLS, the red channel contains a color’s hue, for example.

Color temperature is a measure for how cool or warm an image appears (top row of the image). It has a well-defined physical background but basically it’s your white balance setting. It can be adjusted in most RAW converters and although it’s not a color space you can adjust it using the TMI system which includes a magenta-green-value in addition to the orange-blue color temperature axis. It’s available in Shake and Nuke and I’ve made a macro that brings it to Fusion.

color temperature in Nuke
— anonymous

I think there’s no color temperature node in Nuke, but I adjust the temperature of an image using a Gain adjustment:

Open the gain color wheel and enable the TMI sliders if they’re not yet visible. Then, adjust the T slider to your liking. The image might appear brighter or darker now so as a second step, I use the V slider of the HSV group and bring it back to 1.0. This makes sure that the image stays as bright as before (that’s not totally true, but it’s a good rule of thumb. Of course you can tweak every slider to your liking).

I choose the ColorCorrector instead of Grade or Multiply because it has a saturation slider that is applied before the gain and can be used to make the warm or cold tint of an image stronger (if you desaturate the image completely before tinting you’re doing what Photoshop’s Hue/Saturation adjustment calls colorizing the image).

game of thrones color grading
— anonymous

That’s funny. I’m no authority but a while ago I made a blog post on that topic. And coincidentally it involves color temperature 🙂

Trailer Shot

The fruits of my labor (and Jan’s plus of a bunch of other hard-working colleagues in lighting, animation and fx simulation of course).

Moving Heaven And Earth

This August, I’ve been working at Sehsucht Hamburg on a commercial for Dodge Ram. It’s online now so watch it in all its glory:

Amongst other things, I was responsible for compositing the shot of the car bursting through the dust cloud, wire removal work on the eagle shots and the night-time “pack shot” at the end.

Software used: Nuke, Mocha
Full credit list available here.

Here’s a small breakdown video:

VFX/Nuke Blog

I’ve just discovered that Jan Burda, a very talented compositing artist I’ve worked with in the past, has opened up his own blog. He has written some Nuke tutorials, so head over to his place and have a look!