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    I`m also still very confused about all the places you can input different values getting totally different results. Maybe I`m missing something but the thing I can`t wrap my head around is: why does the editor under lit > ev100 value differ vastly from setting ev100 in a PPV under exposure. shouldn't min max brightness (Exposure) translate to ev100... In my scenes editor ev100 set to 6 (value for interior lighting taken from wikipedia) matches to something like min max brightness set to around 70.... (under auto exposure in PPV)

    In order to match the viewport ev100 of 6 to the PPV min/max brightness of 6 I need to do an exposure compensation of -3.7

    I`m pretty sure I`m doing it wrong... but I`d love to understand where I went wrong

    (my scene lights are around 500-5000lm btw and I`m also trying to figure out if those settings are correct. It`s not helpful to see that the unitless value of 1000lm is 49735. that irritates me even more)
    Last edited by akaChrisV; 11-15-2018, 06:44 AM.

    Comment


      Originally posted by rosegoldslugs View Post
      So your original post is about the auto-exposure relying on EVs only? Definitely did not get that. Your images led me to believe your results were not expected because you said you didn't understand EVs

      Is there a reason you're trying to use the manual one so much? I get the desire to have them both using identical features, but there's very little reason to use the manual mode so I'm just curious. I guess if you're actively trying to replicate someone's setup that isn't covered by the EV configurations or the new DoF is tied to the manual exposure settings(I don't even know if that is on the roadmap or not...), but otherwise I'm at a loss if the visual result is identical. Maybe I'm missing something
      ****...I just accidentally deleted everything I replied before submitting it XD

      Well...An epic misunderstanding between the two of us I would say

      My point is this: when you build a game, you usually have in-game cutscenes. Now you have lighters working on the level and lighters working on the cinematic team. When you have a seamless transition from cutscene to gameplay, you want to make sure both cameras look the same (while the gameplay one allows for variable exposure of 2-3 stops, for example, to keep gameplay somehow dynamic) Why is there no shutter speed setting on auto exposure? what shutter speed is it using? To me, it's just a black box

      Now if the cutscene guy sets up ISO 100 and a shutter speed of 1/100 (that's usually the default for these rules...1/100 or 1/125)....he might decide to go with f9.

      Sky has around 5000 cd/m2 and the sun is about 65 000 lux for example. So now this looks great. Now the level lighter wants the map when you play it to look exactly like the cutscene to make transitions as seamless as possible (or the other way round, the cinematic guy wants to use level settings).

      Now one of the 2 has to either do some math or choose some super unintuitive settings to make them both work together (also maybe including some trial and error). Why not allow both of them to copy/paste the same values around? DONE!

      Why build an extra and unnecessary wall of confusion and additional steps around this when it could be so easy and straightforward?

      Again, it just puzzles me, feels incredibly arbitrary and based on what's going on in the forums you can clearly see that people struggle with it.

      Can a pro use this? Of course! Is it nice and straightforward? Absolutely not. And that's the only thing I am trying to say

      We have been there at DICE as well...and we had tons of issue where level and cinematic stuff was constantly out of sync. We actually went as far as to combine all that stuff into a tonemapper node! Level lighters and cinematic guys all use that same node and share the same settings across everything. Works like a charm and is just great!

      Cheers
      Check out UNREAL 4 Lighting Academy
      https://forums.unrealengine.com/show...ng-like-that-)

      Comment


        Sometimes I wish that in-game cameras could work like a human eye... oh well.

        Just out of curiosity, is it normal that without reflection probes scene looks like that? Directional light's at 70000 lux. (Definitely legit for an otherworldish style though...)
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          Originally posted by GranMinigun View Post
          Sometimes I wish that in-game cameras could work like a human eye... oh well.

          Just out of curiosity, is it normal that without reflection probes scene looks like that? Directional light's at 70000 lux. (Definitely legit for an otherworldish style though...)
          not enough info on your general setup....could be anything^^
          Check out UNREAL 4 Lighting Academy
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            Well, there's also an atmospheric fog and a skylight, both with default parameters. DL and SL are stationary, lighting is baked. No background. With dynamic sun it looks something different, by the way.

            Oh, wait. It looks normal during gameplay. Wha?..
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            Last edited by GranMinigun; 11-15-2018, 10:22 AM.
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              Originally posted by Daedalus51 View Post
              .. Now the level lighter wants the map when you play it to look exactly like the cutscene to make transitions as seamless as possible (or the other way round, the cinematic guy wants to use level settings)..
              Yeah that makes sense. I don't think we ran into that issue since our cutscenes are a little different, but I guess the only way around that currently is using the EV chart on Wikipedia and matching the manual settings. Interesting idea about the 'tonemapper node' though.

              Originally posted by GranMinigun View Post
              Well, there's also an atmospheric fog and a skylight, both with default parameters. DL and SL are stationary, lighting is baked. No background. With dynamic sun it looks something different, by the way.

              Oh, wait. It looks normal during gameplay. Wha?..
              If something appears different in gameplay vs. editor (or by toggling 'G' in the viewport), then you most likely have something disabled in the viewport properties compared to what is enabled in the Post-Process Volume. Just hit the "Reset Viewport" option to verify easier. It's going to look weird though, because the Atmospheric Sky doesn't reach the average sky luminance by default, so it'll be a bit darker.

              Originally posted by akaChrisV View Post
              I`m also still very confused about all the places you can input different values getting totally different results... but I`d love to understand where I went wrong

              (my scene lights are around 500-5000lm btw and I`m also trying to figure out if those settings are correct. It`s not helpful to see that the unitless value of 1000lm is 49735. that irritates me even more)
              ​​​They should be identical. Just to be sure, you have the new checkbox in the Project Settings enabled that switches the auto-exposure in the PPV to use EV100 and not the f-stop? It'll change the text beside the input

              Setting up lights is a little tedious, purely because there's sooooo many variations with drastically different intensities. I've seen readings of incandescent bulbs from 8 lumens up to 4000 lumens. It's better to just get them in a ballpark and adjust based on artistic liberties, unless you can find specific values for something you're recreating.


              Lighting Artist II @ Crystal Dynamics
              Former Lighting Artist @ Obsidian Entertainment
              ArtStation

              Comment


                Originally posted by rosegoldslugs View Post
                If something appears different in gameplay vs. editor (or by toggling 'G' in the viewport), then you most likely have something disabled in the viewport properties compared to what is enabled in the Post-Process Volume. Just hit the "Reset Viewport" option to verify easier. It's going to look weird though, because the Atmospheric Sky doesn't reach the average sky luminance by default, so it'll be a bit darker.
                Nah, default and game view are same, only playtest looks normal. But that's because instead of deleting reflection probe I just hid it. After deletion in-game scene also looks alien. And I don't have a post-process volume, forgot to say.
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                Comment


                  Originally posted by rosegoldslugs View Post

                  Yeah that makes sense. I don't think we ran into that issue since our cutscenes are a little different, but I guess the only way around that currently is using the EV chart on Wikipedia and matching the manual settings. Interesting idea about the 'tonemapper node' though.



                  If something appears different in gameplay vs. editor (or by toggling 'G' in the viewport), then you most likely have something disabled in the viewport properties compared to what is enabled in the Post-Process Volume. Just hit the "Reset Viewport" option to verify easier. It's going to look weird though, because the Atmospheric Sky doesn't reach the average sky luminance by default, so it'll be a bit darker.



                  They should be identical. Just to be sure, you have the new checkbox in the Project Settings enabled that switches the auto-exposure in the PPV to use EV100 and not the f-stop? It'll change the text beside the input

                  Setting up lights is a little tedious, purely because there's sooooo many variations with drastically different intensities. I've seen readings of incandescent bulbs from 8 lumens up to 4000 lumens. It's better to just get them in a ballpark and adjust based on artistic liberties, unless you can find specific values for something you're recreating.

                  I honestly believe the best we can do here is nail the exterior and then derive what looks good from it for local lights. These values seemed a bit weird for me so far as well (looking again at my example of that 1000 lumens light bulb in my living room and comparing what I photographed from it with in engine results) and I especially struggle with those angle things in regards to lumen.

                  If you want to make it really correct, a light (spot) using lumens would need to react according to it set cone angle. Meaning: while having the same amout of energy distributed, the perceived brightness varies greatly depending on covered surface (read: angle of distribution).

                  So there is that as well^^

                  Cheers^^
                  Last edited by Daedalus51; 11-16-2018, 02:55 AM.
                  Check out UNREAL 4 Lighting Academy
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                  Comment


                    So... I've done a little experimentation with my scene and found something interesting. Maybe a bug.
                    Same setup: stationary directional and sky lights, atmospheric fog, and one sphere reflection probe. Everything at default settings, with the exception of DL: its intensity is set to 70000 lux.
                    On the first screen is how scene's lighting normally looks with reflection probe (the intended look). On the second one reflection probe is hidden (or deleted, doesn't really matter) - materials go wild, sky is normal, and it looks like that the guy at the right side is the only survivor. Note that if we'll check reflections visualization, there won't be any wild overbright. But if we'll turn specular off, like on the third screen, - everything's back to normal (well, mostly).
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                      I feel like some sort of better documentation or explanation on what has been changed is really needed. Ideally it would be a good idea to have Epic do a livestream with the people responsible for the implementation explanaing the new system and addressing common complaints from this thread and previous workflows.

                      If not, someone from the community that can get all the nuances. I'm familiar with photography terms but not a pro lighter and reading this discussion on the current state of things did nothing to clarify what's going at the moment and would make me rely on eyeballing values as always anyway.
                      Last edited by MDiamond; 11-19-2018, 08:35 PM.

                      Comment


                        Originally posted by MDiamond View Post
                        I feel like some sort of better documentation or explanation on what has been changed is really needed.
                        One thing that did not make the documentation with this most recent update for 4.21 is a section detailing the workflow for using the PLUs and Auto-Exposure. It's something that I want to add along with some reference values to use for different lighting situations (ie, sunny day, overcast, night, etc) that are in line with what you can find on other sites with tables of exposure values (for example, Wikipedia).

                        Just know that it's still on our minds to add these things and reduce the confusion (as much as possible). Unfortunately, I don't have an ETA, but I'll push to get something added before the end of the year (which isn't really that far off!).

                        Tim Hobson | Learning Resources | Epic Games
                        UE4 Documentation

                        Comment


                          For me this whole physical light thing is still not working out at all.. I tried to setup a night scene based on this rule here... https://en.wikipedia.org/wiki/Looney_11_rule
                          After importing and tweaking my custom HDRI Skybox and camera values, Shutter Speed 200, ISO 200, F-Stop 7 to 11 i throw in a Pointlight in my scene with a value of 900 lumen or 1300 lumen and i see nothing... the light is still pitch black. Values above 100.000 start to give me some light which is kinda crazy.

                          Comment


                            Originally posted by A-J-K View Post
                            For me this whole physical light thing is still not working out at all.. I tried to setup a night scene based on this rule here... https://en.wikipedia.org/wiki/Looney_11_rule
                            After importing and tweaking my custom HDRI Skybox and camera values, Shutter Speed 200, ISO 200, F-Stop 7 to 11 i throw in a Pointlight in my scene with a value of 900 lumen or 1300 lumen and i see nothing... the light is still pitch black. Values above 100.000 start to give me some light which is kinda crazy.
                            For a night scene that's not correct - The Looney Rule is meant for taking pictures of the moon/moon's surface, not a whole night scene. You can get a better idea of a night scene exposure here: https://en.wikipedia.org/wiki/Exposu...xposure_values

                            I'm still personally struggling with the candela/lumen units. I still feel like I have to multiply all the units by 10-100 to "feel" right and that's frustrating not knowing for sure. Daedalus51 mentioned this very early on in this thread, but I haven't really seen a response for it, unless I'm missing something.

                            Some documentation/example scene I think would do wonders for a lot of questions here in this thread.
                            Lighting Artist - Defiant Studios

                            Comment


                              Originally posted by k.mermelstein View Post

                              For a night scene that's not correct - The Looney Rule is meant for taking pictures of the moon/moon's surface, not a whole night scene. You can get a better idea of a night scene exposure here: https://en.wikipedia.org/wiki/Exposu...xposure_values

                              I'm still personally struggling with the candela/lumen units. I still feel like I have to multiply all the units by 10-100 to "feel" right and that's frustrating not knowing for sure. Daedalus51 mentioned this very early on in this thread, but I haven't really seen a response for it, unless I'm missing something.

                              Some documentation/example scene I think would do wonders for a lot of questions here in this thread.
                              Yeah i also saw the video from Daedalus51 but i was thinking that this "issue" is kinda fixed since we are what 2 UE versions ahead from the version he is using in his video ?
                              Lumen and Candela values are so off for me no matter if i try a day interior scene with interior lights or a night scene.

                              Ouh i thought the looney Rule was kinda the oposite of the sunny 16 rule, thanks for clarifying this. I can't find any night values on the wiki page you have shared... What would be the right values for a night scene/night interior scene ? I guess Shutter and ISO at 100 and a low F-Stop value ? i also had some problems to find the lux values for the moonlight intensity. Wiki says for full sun light 100K to 125K Lux, for moonlight it says 0.1 to 1 Lux, which seems kinda low for me.

                              Comment


                                Originally posted by A-J-K View Post
                                Wiki says for full sun light 100K to 125K Lux, for moonlight it says 0.1 to 1 Lux, which seems kinda low for me.
                                That's correct. The range between the sun light and pretty much anything else, practical or natural, is extremely high. Even the range of the sun itself between noon and sunset is pretty extreme. The Lux values also include the sky contribution, so your light value will be slightly lower.

                                For night time exterior, you'd use an EV of -6 to 4, depending on what type of light your subject is under, including moon phases. For night interiors, an EV of 4 to 8 also depending on what type of light is used. If you want to use the manual controls, pick from the chart here that corresponds to your desired EV and f-stop. https://en.wikipedia.org/wiki/Exposu...amera_settings
                                Lighting Artist II @ Crystal Dynamics
                                Former Lighting Artist @ Obsidian Entertainment
                                ArtStation

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