ADOBE AFTER EFFECTS: Forum Expressions Tutorials Creative Cloud

Lens Blur errors

COW Forums : Adobe After Effects

<< PREVIOUS   •   FAQ   •   VIEW ALL   •   PRINT   •   NEXT >>
Aaron Pozzer
Lens Blur errors
on Mar 26, 2015 at 1:59:33 pm

i know im not the only one who has problems with the CC Lens Blur plugin. iv googled for solutions to this problem but i still cant figure it out.

when i use a depth pass to as an input for the Lens Blur plugin, i always end up with sharp edges on what is being blurred, then the interior gets blurred, and theres some sort of blur outside of the edges, but there is always some hard line in there and it just looks terrible.

dof.jpg

i have tried rendering my depth passes without AA, as i read this helps define an exact area of blur or no blur, and can fix this sharp edge artifact. no luck. i've tried precomping the foreground and background, and then applying the blur onto that so its bluring a solid image, not a layer ontop of other layers. no luck. i've tried using it on an adjustment layer in the layer stack. no luck. i've tried adjusting the image interpration/color management settings. no luck. i've tried Frishluft DOF plugin, same error more or less.

So, either im missing some fundamental basic principle of this technique, or all these plugins that try to do this are useless. really hoping its just me and someone can tell me what i overlooked.

thanks.


Return to posts index

Joseph W. Bourke
Re: Lens Blur errors
on Mar 26, 2015 at 9:03:58 pm

Is there possibly an issue related to the color bit depth you're using in your project? Try upping the color bit depth to 32 bit and see if you see a difference. It says in the Adobe help that working in lower color bit depths can cause quantization:

https://helpx.adobe.com/after-effects/using/blur-sharpen-effects.html

Joe Bourke
Owner/Creative Director
Bourke Media
http://www.bourkemedia.com


Return to posts index

Michael Szalapski
Re: Lens Blur errors
on Mar 26, 2015 at 9:34:02 pm

Sounds like the Camera Blur bug that people have been complaining about. Please file a bug report [link]. The more they get, the higher priority this issue will get.

- The Great Szalam
(The 'Great' stands for 'Not So Great, in fact, Extremely Humble')

No trees were harmed in the creation of this message, but several thousand electrons were mildly inconvenienced.


Return to posts index


Aaron Pozzer
Re: Lens Blur errors
on Mar 26, 2015 at 10:50:54 pm

i was at 16bits, but ill try 32 next time i open the project.

as for filing a report, people have been complaining about this for years. i dont think they care.


Return to posts index

Walter Soyka
Re: Lens Blur errors
on Mar 27, 2015 at 9:23:17 am

[Aaron Pozzer] "as for filing a report, people have been complaining about this for years. i dont think they care."

People complaining about a feature in a forum post don't get tracked. People complaining about a feature in bug reports go in a real person's inbox, are logged in a database and are discussed in meetings.

Really, filing BRs is the best way to effect change.


[Aaron Pozzer] "i tried frishluft again, and it is giving better results but still not perfect. where details overlap it gets confused. i played with the render settings in the C4d file a bit, and that helped by further smoothing the edges, but its still not great, and the CC filter is a joke compared to Frishluft."

All post effect Lens blur solutions will have some version of this problem, as they cannot "see" behind/around object edges to know what to blur and mix them with. Doing DoF in-camera in C4D is slower but shouldn't suffer these artifacts.

If those panes are supposed to be transparent, then this is even harder to do as a post effect because the depth map is showing the distance from the camera to the pane, not the distance from the camera through the pane to whatever else you can see behind it. You might want to hack together your own depth pass by turning all materials white and illuminating them with linear falloff from a light at the camera position.

Walter Soyka
Designer & Mad Scientist at Keen Live [link]
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
@keenlive [twitter]   |   RenderBreak [blog]   |   Profile [LinkedIn]


Return to posts index

Aaron Pozzer
Re: Lens Blur errors
on Mar 27, 2015 at 12:30:07 pm

thanks for the response walter. what i meant was that ive read plenty of people complaining about this. not just here, and i wanna say as far back as cs5. i have looked into this before, and for some reason that sounds familiar. so if it was a priority for them to fix it, or develop a better way, they probably would have done so by now. but ya, i guess another bug report wont hurt.

there also must be a solid way of doing this because post DOF is something that im sure big studios using nuke, etc, use all the time. if it wasnt something that could be done 100% correctly, i doubt it would be an acceptable technique. iv worked in 3d studios doing vfx, but always on the 3d side, never in comp... so i never saw what they were using (nuke, combustion, etc) comp wise to achieve the DOF after the fact.

re: the squares. thankfully no, they are not transparent. i know that creates a whole other impossible depth situation. i did think about activating DOF in cinema, but for the client this is going to, i doubt they would even notice the DOF... so right now im more just trying to solve it for my own personal satisfaction.


Return to posts index


Walter Soyka
Re: Lens Blur errors
on Mar 27, 2015 at 2:00:46 pm

[Aaron Pozzer] "there also must be a solid way of doing this because post DOF is something that im sure big studios using nuke, etc, use all the time. if it wasnt something that could be done 100% correctly, i doubt it would be an acceptable technique. iv worked in 3d studios doing vfx, but always on the 3d side, never in comp... so i never saw what they were using (nuke, combustion, etc) comp wise to achieve the DOF after the fact"

I'm not saying that Camera Lens Blur is not messing this up! Just that there are some operations in a post lens blur that are necessarily guesses. Things that you have no way of knowing for sure from a flattened image, very similar to the problems inherent in motion estimation.

But comp is an endless string of hacks to make the image look good, not necessarily to look right, of turning lemons into lemonade.

If you have bad edges in the blur, do what a comp artist would and attack the edges. In a flat render, you might isolate the edges from the depth matte and treat them independently in your comp. If you have layers, you might erode the edges just a touch pre-blur.

You might be able to get better edges in the first place by supersampling the depth matte.

Walter Soyka
Designer & Mad Scientist at Keen Live [link]
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
@keenlive [twitter]   |   RenderBreak [blog]   |   Profile [LinkedIn]


Return to posts index

Aaron Pozzer
Re: Lens Blur errors
on Mar 27, 2015 at 2:44:39 pm

i saw a video where a guy rendered his depth pass at 3840 instead of 1920. then scaled up the beauty pass, applied frishluft, then precomped and scaled the whole thing back down. slight improvement.

ya, i know no system is perfect, but its just that something like this, or at least the posted image above, there should be no errors. its an edge, theres nothing behind it. pretty simple.

i can try and fiddle around with some sort of edge filtering. i would ask my comp friends, but no one comps in AE.


Return to posts index

Aaron Pozzer
Re: Lens Blur errors
on Mar 27, 2015 at 12:40:00 am

just had a peak at the ae file. 32 bits DID NOT fix anything.

should mention im using cineware and bringing in render passes directly from cinema 4d, rendering on the fly. i tried frishluft again, and it is giving better results but still not perfect. where details overlap it gets confused. i played with the render settings in the C4d file a bit, and that helped by further smoothing the edges, but its still not great, and the CC filter is a joke compared to Frishluft.


Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2017 CreativeCOW.net All Rights Reserved
[TOP]