Simon Edmondson Posted September 18, 2017 Share Posted September 18, 2017 Having some trouble with renders using Ambient Occlusion. This was rendered with 5 passes and Ambient sampling set to 100%. Its a reflection in a glass surface but, I've had similar troubles in non reflective surfaces too, although this is the most extreme example so far. This is it without ambient settings The ambient render is VGA because its taking a very long time to render at 1080. Can anyone kindly suggest a cause and possible cure for the problem ? Thank you simon Quote Link to comment Share on other sites More sharing options...
Hash Fellow robcat2075 Posted September 18, 2017 Hash Fellow Share Posted September 18, 2017 How about if you did the reflection portion as a separate pass without a mirror and composited it in? You'd flip the camera around and shoot it from the opposite angle. In compositing you could more easily play with the contrast and brightness of each element to get the right mix. Quote Link to comment Share on other sites More sharing options...
Simon Edmondson Posted September 18, 2017 Author Share Posted September 18, 2017 Robert. Thank you for your help and reply. Must admit, would prefer to do it as a single shot rather than composite it, even with very long render times, but, these are this afternoon's comps. Still working on the composition. regards simon Quote Link to comment Share on other sites More sharing options...
Hash Fellow robcat2075 Posted September 18, 2017 Hash Fellow Share Posted September 18, 2017 Does anything happen over on the motor cycle side of the scene? Quote Link to comment Share on other sites More sharing options...
John Bigboote Posted September 19, 2017 Share Posted September 19, 2017 Isn't there a 'thing' with AO and transparency...? Like a feature... transparent AO? Are you activating that? Have you looked into using FakeAO? One feature it offers is the ability to render your AO pass separately and add it back in in post... Quote Link to comment Share on other sites More sharing options...
Simon Edmondson Posted September 21, 2017 Author Share Posted September 21, 2017 Isn't there a 'thing' with AO and transparency...? Like a feature... transparent AO? Are you activating that? Have you looked into using FakeAO? One feature it offers is the ability to render your AO pass separately and add it back in in post... Mat Thank you for your reply and help. Much appreciated. Pardon the tardy response, I've been a bit ill the past few days. Its only using standard AO, not the transparent kind. The cautionary note that it was "very slow" put me off trying that as it was taking nearly 5 hours per frame as it was, even longer in in V15 which is what I set it up in before switching to V17. I've not heard of fake AO, do you have a link where I can read up about it please ? I am trying to keep the post work to a minimum if possible. This final scene, might require it but, I was hoping to keep it all within AM as a standard render, if only for the sake of simplicity. Robert earlier suggested using the technique of comping over black figures, which was then used for the celebratory toast scene, which may be needed for others, but its getting a bit overwhelming as it is. Regards simon Quote Link to comment Share on other sites More sharing options...
Hash Fellow robcat2075 Posted September 22, 2017 Hash Fellow Share Posted September 22, 2017 Fake AO is called SSAO in A:M (Screen Space Ambient Occlusion). It's a bit like a Photoshop filter that works on the 2D image as a last render step. It is fast but it has many parameters that must be set right to get a result that resembles "real" AO. You have to have a clear mental or reference image of what the goal is. The settings will be different for every shot. For indoor scenes within walled rooms it is the only option for AO effects since AO light doesn't reach things within walls. Quote Link to comment Share on other sites More sharing options...
Simon Edmondson Posted September 22, 2017 Author Share Posted September 22, 2017 Robert Thank you for your reply. Do you have a link I can look up to read more about it please ? I'm trying to stay away from the computer over what would have been a holiday but, allow myself to read ... ! regards simon Quote Link to comment Share on other sites More sharing options...
John Bigboote Posted September 22, 2017 Share Posted September 22, 2017 FakeAOCPU and FakeAO GPU... I see a forum search (on my end) yields no results... because of the newer SSAO feature the older post-effect may be politically unfavorable here in Hashland, but here's what I know. About 10+ years back, a user named Jenpy wrote a Post Effect that emulated AO really nicely and really fast- this was well before Hash included SSAO as a feature (Screen Space Ambient Occlusion.) Jenpy's was really nice at first because it worked really well and came in 4 flavors... FastAO-32bit-CPU...FastAO-64bit-CPU and FastAO-32bit-GPU...FastAO-64bit-GPU. SOMEWHERE here on the forum are some wonderful samples with-and-without from Nancy Gormezano and myself. What AO brings to an image is a very important and realistic shading effect- pushing small details to great extent. I love using FakeAO and A:M's hair feature- those 2 features play very nicely together. The GPU version was incredible because you could really-really push the effect of AO to extremes- but it had a screen size limitation of 720 X 486 and could not extend beyond. Jenpy had promised an unlimited update but seems to have fallen away from our forum over the ensuing years. The CPU version works at any resolution, and tho it is not as deluxe as the GPU version- it still works very nice and provides some features SSAO does not, like the ability to produce the AO effect in a separate file pass. (SSAO has a feature called 'SSAO effect only' which I imagine will render only the AO... requiring you to do 2 renders- one AO and 1 regular...) http://jenpy.noob.jp/fakeao/fakeao_e.htm I see that Jenpy now charges $25 (did I buy it in the past? I must have!) Both A:M SSAO and Jenpy's FakeAO are very swift renders... adding a second at best per frame render time. I admit that A:M's traditional AO feature takes way too long to render- provides very little if any effect, and has too little controls. I really have to mess with the settings on the A:M SSAO before I can even see it... and AO is a feature (for me) that once I see what it adds to an image- I want more-more-MORE! This is one of the reasons I enjoy exporting A:M models to Element3D within After Effects... their AO feature is real-time (as in FAST!) and you can push it and keyframe it to your hearts content. Quote Link to comment Share on other sites More sharing options...
Simon Edmondson Posted September 27, 2017 Author Share Posted September 27, 2017 Mat pardon late reply.Thank you very much for the info. I shall give it a whirl in a couple of days. I'm taking a short break from the project to work on something else. By way of respite. I've been working on it so long and so intensively that I'm not sure I can 'see it' properly anymore., so a break is needed. regards simon Quote Link to comment Share on other sites More sharing options...
Simon Edmondson Posted September 29, 2017 Author Share Posted September 29, 2017 I changed the composition and rendered it out. It took a long time, 2 hours 50 at 50% AO sampling, but no 'noise' in the render. Curious. I've set another going at 75% sampling. Hoping that will be noise free too. I will try to follow up Mat's suggestion while the render is going through. Thank you to everyone for their help. regards simon Quote Link to comment Share on other sites More sharing options...
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