Advanced Keying: High-End Workflow for Top Results on Tough Problems

in this tutorial i want to walk you through a more advanced keying process and my main focus here is to explain to you how i separate out the different individual steps and keying that i do so i have a not too complex shot in front of me so this lady here is trying to uh destroy the apple and fails miserably and for no reason whatsoever i want to put her in this living room and i instead of just doing the keying i want to go through a workflow through a layout that i have placed with these empty boxes here and i will talk about some pre-processing that i do before even getting started and clean plate generation the actual alpha extraction from the keying process which i will separate out from the d spill process and then talk about corrections i do on the foreground and on the background and combining everything together so this is kind of my my setup in each of these tasks i might split it out even further and talk about things i do on the edges and on the main footage and so on but the main goal here is really to get a template for a more advanced keying workflow this tutorial is kind of a more advanced follow-up to my introduction to keying tutorials so if you're just starting out with green screen i would recommend you have a look at this first i also did a tutorial on the matte control node which i will probably use a couple of times here which might also be helpful otherwise if you just want to get the idea of the overall workflow and the different tasks i can do as part of an advanced keying workflow then this is for you so let's dive in [Music] let me start here from the top and i will fill those boxes not exactly one by one but going in a logical flow so i usually start with setting up something quickly and setting up a delta keyer to start from and look at the alpha channel first you can start in different places but it's something i would do first i have my alpha left and color right from the delta keyer and start by by sampling one of the first things even before i go further into tuning is thinking about whether or not noise has a significant impact it very often has especially on edges you don't always see it right away but if you look at this edge for example you see that's a bit like jagged and just to illustrate this even more if i crank this up a bit you know especially from this side you see that the edge is you know not very smooth and this you can either fix with a pre-blur in the keyer but the blur is well it makes everything soft including hair detail more advanced alternative to blur is doing noise removal and that's what i want to do here so i will do a noise reduction i am in davinci resolve so i can use the resolve noise reduction which is the same as the one on the color page there is a fusion to remove noise but it is only a spatial noise reduction which is quite similar to actually blurring so the temporal one is the better one from davinci resolve so i bring this one in and now you can see on the alpha channel as i bring the temporal threshold here up you can see that the edge let me zoom in even further make this a tiny bit larger you see the impact on the edge so it's really helping the edge at the same time of course you have to look at the hair detail but often a tiny bit here is already doing quite a lot without destroying too much hair detail so noise has a big impact on keying and noise removal is almost always a good idea if you do see that even small amounts will destroy some detail somewhere you can do it locally so you could decide to exclude the hair with the mask and do the noise remove everywhere else to get nice clean smooth edges where you have smooth edges but retain all detail where you have like fuzzy hair details so this is pretty much it what i do for general pre-processing you can decide to do color corrections also before you start with the delta keyer in some cases it might help if you have like some overblown um some overblown highlights or so something not very well exposed it can help to reduce this but generally the delta keyer is not very sensitive to overall brightness like bringing up gain or lift will not do much to the delta gear because it looks more at relative differences between the individual channels what does help is color corrections that impact those relative differences um sometimes doing a bit of gamma correction which you know takes the image in the middle uh bringing it up a bit or down a bit can sometimes help however it's a bit difficult to see when it makes sense and when not in my experience i did a few comparisons with different shots you can bring in brightness and contrast and do like a gamma change when you do it you need to sample again because this impacts now the green background color so you need a new sample right in my experience whenever this was helping to bring up the gamma a little bit or bring it down a little bit in those cases i could achieve a similar result or even better result by using the gain slider here so this is also a pre-processing kind of step which is built into the delta keyer and it seems to have somewhat similar impact in my experience i have seen a few people who also decided to bring the footage into a different color space for keying so i'm working in linear color space infusion this is the default if you use resolve color management or you can set it up manually i have done other tutorials on that um i heard from some people that working in rec 709 was giving them a better alpha solution if you want to do this i would do it up here as part of pre-processing but then use linear color space for the final compositing in each case if you set up anything like this and i i will probably not use the brightness contrast let me delete that again but if you do anything like this you may not necessarily want to do this for your final composite even the noise reduction the noise reduction helps the keyer but it may not be justified for the final composite it could also you know destroy like detail in the foreground i only need it for the edges i don't need it like in general so if i don't want to use it that's not a problem because i can use just the alpha channel from here in my overall flow and ignore the the color here ignore the denoise ignore everything just use this for the alpha channel and then apply the alpha channel a bit later i will get to this but first let me continue setting this up a little bit so here in the key section i will not use the pre-blur now because i have the noise removal i might use the gain a bit let's see if it makes sense a little bit of gain can help but often it is a compromise with regards to hair detail so i would be very careful on this the balance can help because it moves between and sorry i should undo this i just did this for demonstration so let me undo this this was just to demonstrate the edge detail so i should judge my gain first before i do any further matte refinement this can help balance can sometimes help ignore the color changes i'm only looking at the alpha channel now balance shifts between the other two channels so for a green background that shifts between red and blue so it gives some more emphasis towards the comparison between red and green or the comparison between blue and green in that channel comparison that the kia ultimately does internally so this is an internal parameter and sometimes it can help a bit if your image tends more towards red or more towards blue you can use this here it helps a little bit it doesn't solve everything it certainly doesn't solve the uneven background and just to be sure let me sample one more time a sample you know with this just to make sure i sample without the color correction i had in between so you see this is getting quite good but i definitely have uneven background i can generally fix the uneven background by using either the pre-mat or a clean plate i tend to use a clean plate in more sophisticated solutions this is a quick inbuilt solution but there are very different ways of creating a clean blade and you can do all of them externally i will use the clean plate tool here if you have sometimes you might shoot a clean plate on set so shoot the same background without the actor might work however the presence of the actress could cause a slight change of the lighting situation or could cause a slight shadow on the background in those cases you might not do well with a short clean plate but you can try often it can help otherwise you can construct a clean blade with this tool and this is basically a simple kind of inverse keying tool so if i bring this in sample the background i sample again near her hair somewhere where it's most important you see that it's kind of clean out her so it's removing her and leaving the green background and i need to make sure i remove her as good as i can so i might usually work with the top slider here first then possibly bring the bottom a bit up and if necessary you have to erode a bit especially if you see hair detail that is being swallowed so you have to work either with this or careful with this just to to get as much as possible from her but leaving the background near her as much intact as possible so that's the offset look at the detail at her hair where you need it most and then yeah get rid of it as much as possible without overdoing it these areas here i'm probably not concerned i can mask them out anyway so i don't really care and then grow the edges a bit usually i grow the edges a bit and then click fill you could also grow them all the way the important part is that around the edges of the subject and here you see i didn't erode enough i need to go further there's still some like almost dirty areas let's do this again so the important part is that around the edges you are growing inwards so that near the edges where the keyer has the most difficult task that you get a good idea of the background which is like matching the background nearby so it's growing inside that's the idea near the edges the rest doesn't really matter okay so this is now my background without foreground and this one i can attach to the clean plate input of the delta keyer this one here you can as i mentioned construct clean plates in many different other ways you can for example use the movement of the actress so she is moving her head and her arm and so on and whenever she moves she is revealing different parts of the background so it's possible to use that as well and use different parts of the background from different frames these are more advanced techniques i'm discussing like all i can think of in my compositing course so if you want to go to that level have a look at my compositing course um but this is a a good start and often it's a bit easier to tune it than with this internal tool and yeah you can have a few additional options to process this as a pre-processing step for the background and then you will see the impact on the key so if i look at the key again with the alpha channel on the left side and let's disconnect you see there's some some areas here and you can see it even better if i bring the gamma slider in let's bring the gamma a bit up you see really the unevenness of the background and attaching it you get this all sorted i didn't worry about the clean plate here and here now this is all far away from the subject even near the table i wouldn't worry too much because i can easily mask all of this off so let's do this next let me build a mask so i use a polygon here let's not attach it and i will probably because there's often problems like i saw some problems down here near the table and so on i can mask this out like exactly it's not very difficult since the table isn't moving i don't need my keyer for the table i will just i do need it here because these these blocks are moving as she she hits this thing so i will move away from these blocks then take her she is moving her arm up so i will give some space on the top and then down here i will again mask out the table like this and use this as a garbage mask so garbage matte and invert so now i have gotten rid of pretty much everything you can do this before the clean blade you can do it afterwards it doesn't matter just at some point i build my garbage mask i know that for keying i focus on the subject not at the area around sometimes you have to animate it sometimes you need more sophisticated garbage masks sometimes you can manipulate an existing key into a garbage mask so these are the different options here which you can continue with let's look again at the foreground and let's bring this a bit down to reveal any holes and yes there are let's see if we can tune a bit more now from the matte section so i can tune the matte here you can do it outside with the matte control or you can do it inside here i usually start with like the softest areas that i need like the hair detail and see if there's some some tuning i can do here and then if i need to fill in more or work on other areas i might separate it out from the delta keyer with a separate matte control tool let's start here on the soft areas the soft hair and i will bring this a bit down and i just see how far i can go before i i ruin my edges over in my hair detail there's a bit here i think there's also some on top or no it's it's not that much it's not that difficult this shot actually so we won't have that much work here but just bringing this in a bit not overdoing it and often combination of this and the clean foreground can help but clean foreground also can help with like speckles and so on but can also easily ruin things so probably again look at the hair yeah here for example and see how far you can go not very far it will immediately destroy some hair detail okay so i don't want to tune the parameters to death i just want to go more on the overall workflow here i often need a hardcore soft comp approach here this might also work for the apple and for these inner problems so let's quickly do this in an alternative way in my beginner introduction to keying i did it with the second delta keyer you can do this or here i will just use a matte control to ramp up the mask inside make this like a really hard mask which i am contracting so that it's working like inside and not touching the edges and possibly blurring a little bit which i here this blur works before the contract if i need to blur it i might do it separately so for example add a blur on the alpha channel and use this so let me bring this into the box sorry about this and i use this now apply this to the delta gear for example with a second matte control like this where i can add this into the solid matte input so i have a solid heart mat which i plug into the other one and thereby get like the best of both worlds i get this soft hair detail which is coming from the original key and i get this heart inside which is you know filling out the holes that i had before so here were the holes and here it's being filled out the apple you know i wasn't so aggressive here but since the apple isn't moving too much and is really in the center i might just use an ellipse and just plug it into the solid mat here and size the ellipse down to just be here so that's fine that covers this area now the apple is completely covered and i don't need to think too much about it here let's go up again do i have any problems outside any noise hardly any so here it looks a little bit soft so again i can go into the first one the outside mask is coming from here here i have the inside mask here the outside soft mask and i might very gently bring this up a bit actually i think this blur is not coming from here i didn't pay attention yeah it's not coming from here this blur is coming from here so i went went too far here so i need to erode this possibly a bit more with a bit of blur here okay because i touched the edge here from this edge mask so it's going going a bit back and forth to make sure that this inside mask is you know softly aligning with the outside mask but it's not hurting it too much the blur is mainly there so that they don't have like hard transitions between the inside and the outside mask so that's where the blur can help a bit but this one here is really you know can really bring it in and if necessary even go like to extremes right yeah okay so just the the principle again i don't go into hours of parameter tuning here one final part the table here that is the not solved by by either of the two approaches here but once again i can use a solid mask for the table especially since i have this polygon here for the garbage mask let's see if i can make use of it and i will just attach a second mask here to my ellipse mask adding it to the solid mask and i will bring this down and i will just use this to fill the table like like this almost so let's adjust this mask a bit i will remove the keyframe from the garbage mask that i'll just mask down here so the garbage mask is being applied after the solid mask so in this case i can use this rectangle to fill the lower area and then the garbage mask makes sure that me align this properly this mask align it alt left if you need to grab the center handle somewhere else all left so to align this mask here so i have filled the table with the second mask you know and these two together are giving my solid mask this one is giving my garbage mask and the garbage mask at the same time is limiting the impact of the solid mask so everything for the masking here together and this is my final alpha channel now this is everything i do on the alpha channel i have uh completely ignored color until this point and i do want to separate this out the delta gear does have an inbuilt diesel algorithm it sometimes works it sometimes doesn't here it has medium results so the apple looks more reddish than before so the apple should probably stay green there again ways to to tune this a bit um but i am getting into trouble once i you know want to for example only specifically work on the apple or you know do some some other forms of manipulations uh also sometimes the spill from the delta keyer sometimes introduces noise in the foreground and also in this particular case because i'm doing the noise reduction before i don't really want to use everything here i don't want to use this image at all i only want the alpha channel from here so i will do a d spill completely separate and i will start by bringing in a matte control here in my d spill box take the original footage with the noise with everything use this for this bill and let's see if this works so the matte control is a often a good option for dsp let's set this to green and then medium i need to bring the slider up almost forget it because it's not there in the delta keyer and then check like to what level you have to go and how far you can go before you are burning the skin so often you need to go till well done you see here on the on the shirt there is like some some green impact which you know is just getting less and yeah you probably need to go to well done to get it done this is one option another option is to suppress color so alternative you could use a color corrector and let me just demonstrate this as an alternative approach so you can go to suppression and do this so you are suppressing green bringing green towards gray um it's an alternative approach sometimes it works better sometimes not you can do all kinds of color corrections right any color correction imaginable you can do it locally etc in this case the apple gets red in this case it gets gray and not that much improvement for the apple so if i don't want a red apple i definitely need to exclude the apple from my diesel operation i could mask it out i don't think it's moving much so that might work if it is moving then that could be a bit of a problem you might have to rotoscope but i could also try to key the apple right so let's try that i could try to key the apple with a separate keyer and very quickly let's go here and select the the apple and i make this a bit smaller and yeah try to get a key let's bring the alpha channel in let's try again and now i'm not looking like for a super sophisticated solution i'm more thinking about a rough solution i will immediately attach a mask to limit my what i'm looking at so i will just make a rough mask like this and i can use this immediately to cut off the table so there won't be any issues from there attach this to the solid matte in this case and invert because i'm making now everything solid and the green apple will become transparent which is just what the keyer does right if you select the apple it just makes the apple transparent one more time yeah maybe i start from here and now i'm i'm relatively aggressive with the apple i think i can be because nor only a gentle color correction i don't really do compositing um so if you just do a little bit of color adjustment and limit this to the green tones and so on um then you don't need such an accurate mask typically the more precise the corrections you are if you do compositing with a completely different background then you need very very good masks just reducing a little bit of green and there's less green in the shirt and so on it will not be visible if this mask isn't perfect nonetheless let's bring this up and i might really you know blur this and maybe erode a bit ups how how far can i go or maybe let's try the clean foreground background yeah that seems to work pretty well for the foreground and yeah so even even less here okay so this is ordinarily this would be a terrible mask but here i think i will just add a bit of let me add another matte control afterwards and add a bit of blur and expand now i need to expand first then blur we will see how it works so i will just use this as a mask on my d spill and you can see if there are any problems do you see any lines or so so this mask is attached to the d spill the d spill now will only work in the white area and even though this key here is terrible i think you won't see it anywhere yeah not really you don't see it really so still these spill everywhere no dispel on the apple and a bit of surrounding of the apple yeah look at the skins of this but you see if i enable disable the this spell here yeah there isn't much on the skin anyway so that's good so it's more on the upper part of the shirt so this solution worked let me bring it down and now i need to apply this and all i need to do is multiply in the mask um lots of different ways to do it if you like the matte control you can use that again you can also use a channel boolean or multiply it otherwise you could also use it later in a merge but i keep things a bit still a bit separate so let me take a matte control and use the whole mask from the top as a inverse garbage mat or you know what sometimes that's confusing sometimes it's easier to you know do a combine alpha it's sometimes easier to read the flow to know okay there's another channel coming in and i do the combine alpha here copy the alpha in and that brings the alpha in but leaves the color values and i need to post multiplied to get rid of all the color values so this way i have applied the alpha channel from the top to the rgb this build image coming from here okay so this is now applied and let me put it on on both sides look at the alpha channel again should probably remove the gamma now we'll probably not need them anymore let me disable them and now this image with the mask i can merge over my background so let's set this up here in the compositing area in this box i will bring in a merge there's already the background coming here which at the moment just looks like this so let me merge this in and dimensions aren't matching so my background is a photograph which is much larger so i need to resize this or bring it to the correct size if the foreground is the size that i need um then i typically just bring in a background and a merge and just merge the other background over a dummy background which is like a fast way of changing the size so here i have now a dummy background which is having the same dimensions as the input the media in one or you can manually set the desired dimension and here i'm merging it over the desired background so that yeah i have my background here let me talk about background corrections since i am in this box here things i typically do in the background corrections first of all think about the perspective think about color corrections if necessary for the background think about noise and lens effects so everything camera related how the background should match the new foreground so these things i perform on the background you have to decide whether the background is the leading image did you uh key something in order to bring it into an existing background that you might use in other shots or is your source footage like the leading footage which you want to use and the background should just match the foreground both approaches are valid so if i need to do perspective changes then i bring in either a corner positioner or if it's something simple i might actually bring in a dve tool so this is a relatively fast and simple way i bring this in before the merge the dve tool can down here can do these kind of transformations so it does three dimensional transformations on a 2d image so three-dimensional rotations so if your camera from the green screen footage is pointing straight and the other one a bit down or so sometimes a little bit of perspective adjustment can help extremes will typically not work let's also think about the position so to me it looks like this floor is maybe a bit steeper than the table so it could be that the camera that could just be the the lens but could also be that the camera is perhaps pointing a little bit downwards so if this is the case i might you know uh adjust this a little bit although i think here i i probably don't need to definitely not not such extremes uh so i don't really have a lot of reference here but if you have like straight lines in the foreground and the background then you can use those to to see are they really parallel or are they going closer together something like this otherwise it's up to your judgment if you need this so i think here maybe a little bit i can use this now also to bring it down you can also zoom here which is just the z move so it has like the naming from the three dimension the changes like z is like depth but here you can just use it to to zoom as well and once again this was probably totally over doing it so no need color corrections most likely i might do it on the foreground if you need to do it on the background here is a good place to put them here depth of field definitely here so background might need to go out of focus you can use a simple blur actually a defocus node infusion is a more high quality version of making things yeah blurry and out of focus it does also have some lens effects which can be nice or can be distracting but you can tune it here we can see a bit of specular highlights here on these objects if you don't want this you can remove the boom level but you still have the the focus which is typically a bit nicer than a simple blur but you can try and compare last part here in the background correction is noise so i have to add some animated noise or grain i have mentioned it also in the introductory tutorial but either way let me add some film film grain is the tool for it film grain film noise it's usually you can use the same tool there are other techniques but use one of those the this one here with the fgr behind is the fusion tool which tends to work quite nicely so let me add this and then i tend to look at a dark part of the foreground and similarly dark part of the background especially for digital noise you often see it better in the in the darker areas and yeah make sure you look at it with the same zoom factor you might set it to the same zoom factor so you can easily compare so that we have some some darker areas maybe here on the on this lamp post and then take a few a few frames maybe 10 frames or so and loop it through to see the animated noise and actually i need to bring it into the viewer so i can see it and well even on the bright parts here you can see it quite nicely so i need to definitely reduce the strength probably and yeah so here it's it's quite weak okay this is pretty much it for the background section in some cases you might need to remove a lens distortion if that is the case you can straighten out the background then do the compositing on the straight image without lens distortion and then add it again fusion has some tools for lens distortion the um a tool called um distort i think or even a grid warp can can do the purpose if you have shot like a grid and then you can can manually straighten it with a grid warp and do the inverse again afterwards to recreate the lens distortion if you need to this is kind of a more specialized topic i won't go into here just as an idea of what i'm doing here let me continue with the compositing so i definitely need to do something on the foreground as well if i need to do any color corrections i would do them here on where it says foreground corrections i can actually do them even before i apply the mask so then there's no risk of you know getting the alpha multiplication or anything like this so i can do it here on the full image if i want to can do some color correction here so probably make this significantly brighter let's bring the the gain up on the foreground if necessary you can always enable waveforms as well right so you can go into views and have a waveform from viewer either for all channels or in the options you can also add like an rgb parade you know if it if it helps so pretty much almost everything you can do in the resolve color page you can somehow also do infusion so this might help me with this i might then have to switch a bit back and forth between foreground and background look at the background and see oh okay so some parts here are really really bright uh like going yeah pretty much towards hundred percent and it's a bit more like bluish cold the background whereas the foreground if i look here at the foreground it tends more towards reddish so if you want you can accordingly bring this up to a similar level perhaps even yeah move a bit towards towards blue if you want or maybe do this just in the highlights mid-tones and do it individually i'm not going into a detailed discussion here on color correction so just mentioning that i should be doing it here there is certainly more so in some cases also the foreground could require some blur i mean depends on the shot and the situation right or some defocus it could require noise treatment if you need to match it to the background you might need to do a denoise on the foreground and then add maybe overall noise of everything that's also an alternative approach to noise removal so it all depends on the situation but the color correction is let's say at least the minimum i will do i will then look at the edges individually and there the workflows can be um quite different depending on what you want to do so i could for example use this matte control to manipulate the edges i will definitely judge this like over the final image because now i'm not talking about the alpha channel of the edge well that might also still need some adjustments but that i would do before in the in the alpha channel section here if i need to tuck the edges in or out or so as i have done make it harder make it softer that's one kind of looking at edges but another topic is the color of the edge and the reason is the edge itself is semi-transparent that means that green light was shining through the edge pixels that means originally before the d spell the edge pixels were green or greenish the d spell already removed that and brought that towards neutral but then it depends on the background whether or not that is correct because the new background will shine through those edge pixels and therefore neutral is correct if the new background is neutral if the new background has a strong color if it's like reddish or bluish or so then your edge pixels your semi-transparent edge pixels shouldn't just be neutral but they should match with a new background there are different ways to to deal with this so the simplest one of them is to go here into the matte control into this fringe setting for french gamma shape and color corrections i mentioned it in the video on match control so you can look back at there if you need to do this so here the background is pretty neutral it's pretty much gray yeah even here there's really not much we need to do in this particular case maybe think about the gamma and you can can try you know if you need to bring this up or down a little bit if you feel there's like a dark fringe maybe bringing it up in this case with this bright background tiny bit can help otherwise i will probably not not do much here in this particular scenario if you have very strong colored backgrounds uh if it's uniform you can do it here if you have very strong local contrast then you might do something like a adaptive d spell where you use the background image itself to add spill color into the the spill so then we are going into a bit more advanced workflows again here is not necessary and for this overall discussion of things to do i don't think i will cover it here but generally the idea is you take the background image again use an edge mask to work on the edge itself and there you might use the background color and kind of multiply it with the spill color on the edge again the flow for this is a bit more complicated and a bit more than i want to cover here but this is something how you can inform the edge color decision based on the background in this case i call this your compositing and edge treatment and the reason is that for the edge sometimes you can do the edge color only on the foreground which i did up here in the matte control but sometimes you need to work with foreground and background together to get the most best compositing result and then that's why i set compositing and edge treatment here together where foreground and background meet because it is kind of an overall approach this is also the place where i would think about any other form of edge refinement two things come to mind right away but it all depends on the circumstances sometimes a tiny little bit of blur specifically on the edge can help if you don't overdo it so that's a little bit of a cheat but you know that the foreground and background are artificially put together and the edge is just the place where it's most noticeable and bringing things via color correction and edge correction close together so that it doesn't make sense is a good way but at the end in a realistic film situation pixels do mix right um i mean if you go to if you zoom up enough then you you see pixels where some light from from two places of the edge from left and from right like fall onto the same pixel right where foreground and background like fall onto the same pixel and to simulate this kind of you can apply a tiny little bit of blur for these kind of things you need an edge mask again i mentioned how to build an edge mask in the tutorial on matte control it's one way to build one let me quickly do it let me build this separately let me build this up here you might use it for for different purposes so i will do a bit of blur on the alpha mask and let me set this back to the normal 2d viewer and look at the alpha channel so i will blur this mask a little bit like this and then i will from this blurred version i will subtract and subtract the original one so i will take a second matte control set this to alpha and subtract and yeah connect one to the other and thereby i have a inside edge mask tip if you need an outside edge mask all you need to do is switch foreground and background which you can do via ctrl t now i have an outside edge mask you know little little tricks with these matte control tools go a long way so if you need like a halo around the subject you could get this simply like that anyhow i'm not talking about matte control and building these masks just a reminder that you can do it and can control the width of this here so you can just make a tiny bit of edge mask like this and i will use this mask now on a blur node and blur foreground and background together which i can do if i apply it after the merge so that's why i'm saying like compositing and edge because i'm using the edge from the foreground but i'm doing the blur on foreground and background together with this mask and now maybe one pixel blur is already everything i need let me bring it into the viewer and see if we can zoom in yeah you know it's really subtle we might actually bring this mask a bit up because this is like very faint this is the alpha channel if you look at the alpha values it's like way below it's like 0.1 something like that so you might bring this up just by ramping this up so we have a higher yeah alpha values here and then the blur here will do more again so with without blur sorry wrong tool blur so let me select again the blur tool and just this one one pixel blur yeah so you see it's doing a little bit and you can judge in different areas if it's doing the right thing or if it's if it's if it's a good thing or not and can adjust this further may not be necessary in this particular case so i'm more generally speaking about the kind of activities i might do here so blurring the edge like a tiny little bit could help in some cases a light wrap this is the case if you have like a strong light behind the subject especially then you might observe that light is like wrapping around the subject it is a correct physical phenomenon but it's not needed everywhere so here in this case there isn't a strong light source like directly behind her so i don't expect like a halo from the background wrapping around but these are also things that i'm thinking about here if it's necessary you can do this or build some form of rim light and so on where the background is kind of informing the the foreground and uh manipulating the foreground edges okay i think this is it what i want to cover here this was a long tutorial already and of course there are additional topics like relighting or building artificial shadows or lifting shadows from the green screen so that these specialized topics you probably when you know about the topics and you have the basic tools to build them whatever the problem is you find a place in the workflow to put them in but i think as a good general framework of looking at the topic and working your way through from beginning to end i think this can help so let me make this like the flow completely full screen and have a quick review um or in case you want to take a screenshot you can probably let's see maybe here something like this so starting from my original green screen i'm building a clean plate or i have a clean plate from a different source by the way here i didn't do it on the noise you can also use the noise reduction pipe that into the clean plate would probably be the better flow here i didn't pay attention when building it probably i would go from here to there so um just so that this is actually the clean plate for the correct example or if you have an external clean plate do the same noise reduction on on both so this would be the starting point i'm doing the alpha extraction with whatever mass manipulation trickery i might need in order to get a really good alpha channel so here i'm focusing on a really good alpha channel starting from the softest areas from the hair and the most details and then filling in the rest as needed masking around as needed in parallel i'm working on the d spill so in this case i needed to have some local exclusion from the d spill specifically for the d spill in case of the alpha channel i could just plug this apple just with a very rough mask for the d split itself i needed something slightly more finer so i decided to key and use that key specifically to manipulate my v-spell you can also do spill reduction with different techniques you can use the color corrector node you can use hue curves for spill suppression to remove green component from your image and there are a few other techniques for this spill as well then both on the foreground and on the background you may have to do corrections to match them to each other in terms of color in terms of sharpness in terms of noise in terms of length distortion if applicable so i do these kind of things and then finally i bring foreground and background together and while bringing it together i really evaluate the edges once again and think about the color along the edges and you can do color correction on the edge either inside the matte control or if you have an edge mask like the one i used here you can use this for selective color correction on the edge or for selective blur on the edge and you can use this also to build light wraps and other more advanced topics okay this was it for my overall keying workflow if you have questions on specific steps i can probably do detailed tutorials on one topic or the other this was just to give you like an end-to-end idea of the process let me know what you need let me know in the comments there is a lot of keying in my compositing course and there is a bit of keying in the fusion vfx course so my fusion vfx with resolve is more like a general fusion uh all-round introduction the compositing course really goes into a lot of detail for keying rotoscoping integration multi-pass compositing and all that beautiful stuff so if you're interested have a look at my courses and thanks for watching and see you next time cheers [Music] [Music] fans

Channel: VFXstudy

Views: 4,185

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Id: 0UAn78f6oQI

Length: 46min 58sec (2818 seconds)

Published: Sun Nov 21 2021