FilterForge Tutorial 03: How Rusting Tech Wall was Constructed from Skybase on Vimeo.
In this not-so-much of a tutorial, we’ll take a look at how one of the filters I made some time ago called Rusting Tech Wall was constructed in hopes to give you a glimpse at some of the techniques I use add depth and detail into one filter.
This video does not show how you would go about making specific textures, but it shows you some of the ideas behind creating a filter and what goes into it.
What makes that image look good? Is it the background? The details? The characters? Sure, those do make an image look nice and pleasing to look at. And it does depend on what you’re dealing with as well. If you’re presenting a 3D model, you may have nice textures, interesting shapes, nice flow… whatever it may be the image looks good based on attributes. But let’s say you’re dealing characters in a scene. So what do you do? You try to fit that character within the scenery and you follow common attributes such as lighting, perspective, color… so on. But what really adds to everything is the atmosphere. It’s the extra touch that really really kicks that image from “boring” to “amazing.”
Now, when I say atmosphere, I don’t mean just things like fog, clouds, sky, or just stuff like that. Yes, they’re atmosphere but the atmosphere I’m talking about deals with creating and giving the scene weight, meaning, and spacial context. It’s “color grading” or “color correction” as some people call it, but there’s a bit more when adding atmosphere and I want to discuss that.
So this blog post isn’t really a tutorial, but it shows what I’ve been doing for my thesis film “The Door to Tomorrow.”
Let me give you an example of what “atmosphere” is about. First, here’s a frame from my up-coming film “The Door to Tomorrow.” I received a file from my animator, Robyn Stanford, who animated the characters you see here. The background is by me.
No filtering, just straight compositing
Now some people consider this done. Not in my world. Given the background, the characters here aren’t shaded properly which makes them just float right on top of the background. Ok, the easy way to fix this is to add some form of shading. Fortunately this task is slightly easier for me given that the characters are just flat, 2D shapes in 3D space. All I have to do is add a gradient. Of course, I can go very fancy, but time doesn’t permit me. Now if you have human characters or anything else, you’ll have to work on shadows and that’s a different story. For now, we’ll just keep it simple.
Some moody shading here
So now it’s somewhat obeying the mood of the shot. The light here passes from right to left so I gave the characters a simple gradient (ramp in After Effects.) Not too bad but it needs more. Let’s add some shadows.
Very simple shadows
Now the two characters are interacting with the background a bit more. The shadows here aren’t fancy shadows, and while I would appreciate a realistic shadow, I don’t have time for that. So I came up with a quick way to produce rough shadows. I first duplicated the character layer, then using “Colorama” filter (otherwise I could have used an inverted alpha channel) and turned everything black. I then offset the layer to the left just a tad bit and added directional blu which makes it look like it’s fading by the distance. Very simple but it works in this case.
Next, I created an adjustment layer with more gradients to add further sense of lighting. The overall image looks dimmer now, but we’ll get to fixing that later.
Mood, it's very important.
This part of the film isn’t the happiest moment. Apex (the blue square) tells his friend Arc (the green circle) that he is terminally ill, given that Arc attempts to provide him some comfort. Given the weight of the moment, I felt adding the gradient helps extenuate not only the lighting, but the mood of the shot.
Ok, let’s fix the ultra dimness. Some people would stop here saying it’s “good enough” but of course it’s not! It just looks dimmer and while it does feel appropriate, it doesn’t appeal. To fix that, I added a glow.
GLOW!
Glow really helps. I mean it. It kicks up highlights, blends background colors with foreground colors, and it really adds that “atmosphere” to the scene.
This scene was meant to also be during a sunny, warm evening. So to give it further feeling of time, we’ll do some color grading.
Yup. I'm done here.
Now, you have a sense of time for the shot. The super yellow highlight on the right hand side of Apex does bug me a little, but it’s not such a huge issue.
So we went from just flat… to moody. I generally apply several layers of filters to accomplish the look I want. Given the full scope of the film, it’s important to note the flow and continuity of color and style. This is where color charts and schemes become very very useful. Of course, if you’re doing this independently, you may have already picked up on the style you’re going for so maybe you don’t need schemes and color charts, but you should save presets of color grading chains to help yourself save some time.
I always see people who just apply curves to give the image more contrast (or less.) That’s a good start, and depending on what you’re thinking of you may not need more. But of course, it’s also a good thing to push further and punch the look and feel for the work you’re doing.
Adding that extra touch of color is what makes the image or film powerful. We’re not just talking about “making stuff look good” we’re talking about telling the story through color, lighting, atmosphere… framing… everything.
This post discusses some stuff regarding this filter I produced in FilterForge a while ago: http://www.filterforge.com/filters/9726.html you can download the filter there too.
I’m not really THAT technical with stuff. I honestly don’t know all the math that goes behind each node I use in FilterForge but I have some clues and hints on how some of the stuff works.
Either way, some time ago I wanted to produce a multi-level sharpen filter. Unlike a single sharpen filter, this “dream” filter basically allows for a broad range of sharpening. To do this I used Filter Forge.
Let me show you some pictures of what happens when I use it. First we have our original photograph.
Original Image
The image has not been processed in anyway…. now… for the processed image.
Processed image
This is very subtle (I’m using default values) but you can see some changes in the contrasts of various areas. Some areas “pop” now more than others.
Comparison
Some comparison here so you can see what’s different. It’s still kinda subtle but you can mildly see what’s happening.
What makes it pretty neat is how this sharpen filter works. It’s on multiple levels of detail allowing you to sharpen small, medium, and large details separately. So if you ever want to sharpen a LARGE area then you can turn down the small and medium sharpen filters and leave the large sharpen with higher values. If you want small details to pop, you can do so too.
To show you what can visually happen here’s another shot at the image above.
Vivid!!!
With a couple additional nodes I was able to produce a filter that allows for various degrees of control while sharpening a photograph.
Now for the exciting technical aspect of how this was accomplished! You probably need to click and see at the full resolution
How it was done
The basics go like this. I have multiple highpass filters with different radius settings. The radius values weren’t chosen mathematically, they were chosen based on visual output so nothing fancy there. Then you see this huge stack of Min and Max nodes which allow for combinations of the nodes. This is really the fun part because it’s where I didn’t know what to do. I began combing the highpass nodes using various tools and then I realized I should just stick with min and max because of the way they operated. Also the way they looked seemed valid enough for usage. I then used a blend node (which was set to overlay as you’d expect.)
Now this is the really weird part. There are two things being mixed here: two separate chains for min and max nodes. To combine them both, I used a blend node. I lastly gave the user control over which they want to chose. If they want a brighter image then they can slide the control to achieve what they want visually.
And that’s basically all there is to this filter!
Here are some more examples of the filter in action.
Processed imagery of the streets in Tokyo
Original input picture. Note that it's not very crisp due to atmospheric factors.
And this is what it looks like when processed!
Of course you do have to be careful of over-sharpening images. I just wanted to show you what it basically can do for you.
