Chromatic Abberation - Yay or nay?
polycounter lvl 8
I've noticed that a lot of people are using chromatic abberation on their models. Personally, I don't like it (especially on really nice detailed sculpts) because every time I try and look at a neat detail, my eyes get confused by the coloured outlines of things. It's kind of like looking at one of those optical illusions with the black and white lines that "move." Maybe my eyes are just sensitive...
It seems incredibly popular and I'm not too sure what it's meant to do. I've noticed a few other people aren't fond of it either. What is the purpose of chromatic abberation? Not complaining, just curious more than anything
It seems incredibly popular and I'm not too sure what it's meant to do. I've noticed a few other people aren't fond of it either. What is the purpose of chromatic abberation? Not complaining, just curious more than anything
Replies
Like for me, It kind of hurts to stare at that picture. It's cool, just slightly hard on the eyes. So it's especially difficult when you're focusing on cool little details and you get the same sort of effect.
I think if it conveys what you want it to it's all good, like bad video and scanlines from CCTV or whatever, but I think it's just the new lens flare and alot of people a couple years down the line will be embarassed that they used to abuse it.
Anyhow, in reality CA is a little complex then what Andreas mentioned, it happens everywhere all the time, just harder to notice unless you want to focus on it.
For example, lenses as said, CA around the edges like a Vignette effect, bottles and other glass materials with water will CA harsh light/dark colors, and hair or strands of fine threads on harshly lit background will CA too, like say a Grey Foxes fur on a Snow Background.
Also, fun-fact, sometimes, pending on the object/material in question, the brain will force our eyes to CA the edges so that we can focus on it properly, a la guide-lines of sort of things, so it does indeed have it's basis and uses in real-life. This also helps us in some cases get depth of an object, something which many 2D artist have been doing, a slight CA around the closer parts of an object towards the viewer tend to demonstrate this effect better and help perceive depth better, but again, it must be all subtle, kinda like a skin texture texture, where you don't really see the under-skin colors right off the bat.
However, since many artists tend to be lazyass-wankers with shaders or post, they will slap on the first thing which gives their model a quick 'grunge' look right off the bat, which is why CA in the past couple of years got a bad rep. of looking bad, because said artist use it without understanding on what's it supposed to do.
Don't take this as name calling, it's just a recent example that's fresh on my mind.
http://www.polycount.com/forum/showthread.php?t=103156
This is a case where I feel pain from the effect when looking at the images full-sized. The sharp contrast along the edges keeps pulling my eyes out to the borders where the colors are pronounced. It could be the aliasing or lack of blurriness in the shifts, I can't say.
I've seen presentations that I felt looked really nice, but they also had more going on than just CA on the render. I think I'm mostly in the lens flare crowd.
throwing it on a model render or just a single asset showoff is not a good thing, much like dof
It's fine for a beauty shot, but it doesn't help for more technical shots, wips...
edit : erm well, just exactly what Amsterdam said ^^
i think next gen alot of these effects will come into their own and make a very natural feeling images because we will be able to afford to use them subtly....having said that initially you will have bokeh chromatic aberation et al rammed down your eyes
I agree with m4dcow. As a photographer, we try to get rid of all chromatic abberation to create a pristine print. Yet, getting rid of all of it is a feat in itself and some does remain. I think applying chromatic abberation to a model will work if only done subtly. Combined with a bit of DoF, the model can appear more lifelike. Does it need to be used on every model? No. Does it make every model that it is applied on look like shit? No. It's up to a good artist to determine where and when to use it.
This render has a small bit of CA, and some DOF via Lens Blur in photoshop using the depth buffer in the alpha: https://dl.dropbox.com/u/499159/3PointStudios_Brink_High_ar02.jpg
As a photographer we're always trying to get rid of noise, CA, distortion, etc but these are often used as a way to make a render look more "real", because our eyes are so used to seeing these artifacts in traditional photography, it makes a 3d render look less "computery" when done correctly. These sort of effects are essential when matching a render with video/still photos.
While CA's can often be more pronounced along the edges, it isn't at all true that CA doesn't occur in the middle of an image. CA behavior varies wildly depending on the specific lens you use as well, and newer lenses designed for digital sensors control CA much better than older lenses designed for film cameras. With heavy contrast(black subject on bright sunny sky) virtually every lens will exhibit some sort of CA, even in the center of the photo.
On a more serious note though, sometimes it looks good, sometimes it doesnt, it's not the effect itself that should be blamed but its usage. Same goes for lensflares, they still look good in games when looking at the sun/a strong light-source, while still not being overdone.
no i would look at it like: every real thing you see through a screen is captured on a camera, seeing things within a computer generated image that you relate to a camera on a screen can help suspension of disbelief.
it is in the end of the day a graphical effect, used well it can be great used badly it can be rubbish.
im interested in things like this when they are used for style, rather than realism too, i wander how you could use it to accentuate a graphical stylised game or render rather than realism, has anyone got any good examples of this?
although sometimes i get overexcited and ham it up.
It also depends, if you`re making a beauty render its fine but if you`re making a render to show of the technical side of your model i wouldn't add any of those distracting effects
Also, try telling Daphz Chromatic Abberation is no good, I dares ya!
I don't see the point of putting it on a character...chromatic abberation is supposed to occur on the edges of a photo....so its usually used like a vignette...why would you slap it on a model?
Daphz, fearian says yer shit yo!
Seriously though. Like everyone has said, there's a time n' place for it. When used well and sparringly can be cool.
So can lens flares and film grain.