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    Hi Daedalus51, are you planning to release any new tutorial on how to use the new system to achieve such exceptional results as the one above?
    I´ve been following your tutorial series and I really like it a lot and looking at the images above I think it will be great if you could share some of your tips to get this quality of lighting.

    thanks.

    Comment


      Originally posted by TJAMES44 View Post
      Hi Daedalus51, are you planning to release any new tutorial on how to use the new system to achieve such exceptional results as the one above?
      I´ve been following your tutorial series and I really like it a lot and looking at the images above I think it will be great if you could share some of your tips to get this quality of lighting.

      thanks.
      I might actually do that during the holidays!
      Check out UNREAL 4 Lighting Academy
      https://forums.unrealengine.com/show...ng-like-that-)

      Comment


        Hi Epic! I saw there is now a documentation page about "Physical Lighting Units" (https://docs.unrealengine.com/en-us/...icalLightUnits). It would be great to have also some official guidance on how to make a realistic outdoor lighting setup, as the default values (for lights and in the templates) don't seem correct (or I'm wrong?). Thanks!

        Comment


          Originally posted by Kafumanto View Post
          Hi Epic! I saw there is now a documentation page about "Physical Lighting Units" (https://docs.unrealengine.com/en-us/...icalLightUnits). It would be great to have also some official guidance on how to make a realistic outdoor lighting setup, as the default values (for lights and in the templates) don't seem correct (or I'm wrong?). Thanks!
          Documentation is updated to explain some of the workflow/changes, but as far as reference values go, there aren't any on the documentation page. But there's a ton of information out there that you can start with. Go back through the last ~5 or so pages to find some other examples of real-world values being used in the engine. Tim wants to add reference values though, so perhaps early next year:​​​​​ as seen from his post a few weeks ago:
          Originally posted by Tim Hobson View Post
          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!).

          Tilmann - Nice tests. Good to see things are working for you! I'm always a fan of that "blue hour" type of lighting like in the second shot. The lights/light sources are reading well too.

          You should try measuring some light values next time to go along with your camera settings. I've had pretty good luck with some smartphone apps that use the ambient sensor. Might not be the most accurate, and they're usually full of ads, but the values I've gotten with my Pixel 1 have been in the ballpark range no different than what we get with online resources. Just hold it horizontally, facing up and you can get the measurement like you would with a flat white plane horizontally in the scene, after conversion. To be even more accurate, you could shoot in sLog and send it through the ACES ODT to sRGB
          Last edited by rosegoldslugs; 12-19-2018, 03:19 PM.
          Lighting Artist II @ Crystal Dynamics
          ArtStation
          Twitter

          Comment


            Originally posted by rosegoldslugs View Post

            Documentation is updated to explain some of the workflow/changes, but as far as reference values go, there aren't any on the documentation page. But there's a ton of information out there that you can start with. Go back through the last ~5 or so pages to find some other examples of real-world values being used in the engine. Tim wants to add reference values though, so perhaps early next year:​​​​​ as seen from his post a few weeks ago:
            ...
            Thanks rosegoldslugs !

            Comment


              Originally posted by Daedalus51 View Post

              Good question but a different topic!

              Would need to investigate. Theoretically, there should not be any difference between the two when using exactly the same levels of brightness.

              Cheers!
              Hey Shifu, I use the same workflow as Coach mentioned, especially for the interior scene, I like using specific HDR on skylight to get more color on the secondary bounce.
              However, I've also switched in between the captured skylight and the specific HDR skylight, the brightness in Skylight [Stationary] seems similar, but if I choose static skylight, the HDR specified skylight went way darken after the baking process.

              Probably I did something incorrectly on my bake setting 0_O, would be nice if we have more follow up on this topic XD!

              Comment


                Originally posted by Xiaowantou View Post

                Hey Shifu, I use the same workflow as Coach mentioned, especially for the interior scene, I like using specific HDR on skylight to get more color on the secondary bounce.
                However, I've also switched in between the captured skylight and the specific HDR skylight, the brightness in Skylight [Stationary] seems similar, but if I choose static skylight, the HDR specified skylight went way darken after the baking process.

                Probably I did something incorrectly on my bake setting 0_O, would be nice if we have more follow up on this topic XD!
                Hey!

                Could you guys open a new Thread for this topic and ping me in there so I know where to look?^^

                I might have time to look into this soon and I can also give Daniel Wright a shout after I dug a bit into it and see if there is anything unexpected from an engine point of view

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

                Comment


                  Originally posted by Daedalus51 View Post


                  PS: I totally forgot to mention the bugs I encountered!

                  1. eye shader seems to be broken as eyes render black when using physical values (I have pre-exposure turned on)
                  2. skin doesnt show spec anymore
                  3. the hair of her is set to black, for some reason it renders light brown when using physical values
                  4. black dots on water reflection on the daylight shot
                  The eye shader is broken due to it looking at the scene color (which gives incorrect results when pre-exposure is turned on). So unchecking pre-exposure will fix that or an even better solution is to simply divide your result in the shader with a EyeAdaptation material node. This takes the correct exposure in mind and adjusts it accordingly.

                  An annoyance of this new physcial based lighting workflow are 3D widgets and other unlit UI shaders (VR comes to mind), because they are affected by exposure values. They will look vastly different in every scene because of the huge varying EV values. They will be either too bright or too dark depending on whether you have a night or day scene. Sure it can be easily fixed by adding the EyeAdaption node I mentioned above but it's something people will have to know it exists ^.^

                  Comment


                    Thank you all for the good amount of info on using exposure with extended range, physical light units etc.

                    Here's a very very simple blueprint that you can drop in your scene to convert the Luminance values the Pixel Inspector gives when you sample a surface from cd/m2 to Lux (lumens/m2) and displays it as text in the viewport.
                    I don't know how useful it is (as to convert from cd/m2 to lux is almost multiply by 3 in your mind - well, actually Pi: 3,14149) but I was here resorting to the calculator again and again to get exact values.
                    You have to input the luminance value in the Details Panel to see the result in lux.

                    https://www.dropbox.com/s/9busn0vkbx...or_BP.rar?dl=0

                    (made using 4.21 - there's an exported blueprint and unlit material using emissive for the text - to make it bright only put big values for emissive multiplier in a material instance, or leave with the default text material - I exported them as unreal text objects .copy)

                    Maybe someone can extend the blueprint by adding a reference to the skydome's material/material instance to pick its multiplier parameter, use some math nodes etc, so that the converted value updates automatically. Anyway, a very simple blueprint, but as it was done, why not share?

                    Thanks to the info on this thread I was able to get a properly lit scene using the extended range + exposure in 2 days of experimenting.

                    One question: is there a way to make the Unlit view mode work well with sunlight values like 120,000 lux without blowing up in white? Also the Scene Color buffer visualizer...
                    Last edited by MysteryBlues; 12-26-2018, 01:22 AM.

                    Comment


                      Originally posted by Nepfish View Post

                      The eye shader is broken due to it looking at the scene color (which gives incorrect results when pre-exposure is turned on). So unchecking pre-exposure will fix that or an even better solution is to simply divide your result in the shader with a EyeAdaptation material node. This takes the correct exposure in mind and adjusts it accordingly.

                      An annoyance of this new physcial based lighting workflow are 3D widgets and other unlit UI shaders (VR comes to mind), because they are affected by exposure values. They will look vastly different in every scene because of the huge varying EV values. They will be either too bright or too dark depending on whether you have a night or day scene. Sure it can be easily fixed by adding the EyeAdaption node I mentioned above but it's something people will have to know it exists ^.^
                      Well....it was also said that pre exposure needs to be turned on to fix the other issues or am I actually mixing this up now?

                      Regarding unlit materials, thats exactly how it should be!

                      We had the same issues on Star Wars as the lightsabres use a unlit material with emissive! In reality, if they would have a static value, like our unlit shader, you wouldnt see the lightsabres during day but they would glow strong during night! In movies, they fake it per shot....so using the exposure node in the shader is exactly the correct option for gameplay purposes

                      So I am quite happy for all these things falling into place like this
                      Check out UNREAL 4 Lighting Academy
                      https://forums.unrealengine.com/show...ng-like-that-)

                      Comment


                        Regarding this I said above
                        One question: is there a way to make the Unlit view mode work well with sunlight values like 120,000 lux without blowing up in white? Also the Scene Color buffer visualizer...
                        Actually the (sun) directional light is not blowing the buffer visualizers as I said. It's the skylight. Turning off "Affect world" temporarily for the skylight brings back the values for the visualizers. The directional does not affect/blow them. Weird.

                        Comment


                          Another very simple blueprint to temporarily fix (the lighting for) UnlitMode etc - for when you are checking your Base Color values etc.
                          While we wait for Epic to fix the Unlit mode preview while using the extended luminance range + physical real-world values for lights.

                          https://www.dropbox.com/s/51djjs7vu1...ck_BP.rar?dl=0

                          As you can see in the screenshot, you just have to assign the sun directional and skylight actors, and mark "Check Unlit mode". It will turn both actors to invisible, and the "UnlitCheck" directional light component in the blueprint to visible - this light has the default 3.14159 intensity. Unchecking will revert these lights to their previous visibilities.

                          Again, very simple, but as I made it here, why not share?

                          Comment


                            If you're checking your Base Color values, you should do it in the Base Color viewmode. Unlit includes other things, altering what the actual Base Color is.
                            Lighting Artist II @ Crystal Dynamics
                            ArtStation
                            Twitter

                            Comment


                              Originally posted by rosegoldslugs View Post
                              If you're checking your Base Color values, you should do it in the Base Color viewmode. Unlit includes other things, altering what the actual Base Color is.
                              Ah, thanks for pointing out. I actually meant Unlit, not BaseColor. The BaseColor viewmode works normally. The ones that seem to be blown out in white or black are Unlit, Final Image and SceneColor. Is this correct, or am I doing something wrong, missing a checkbox somewhere...?

                              rosegoldslugs, thanks for all the info on Exposure Values in the thread here. And that tutorial where you re-lighted the sci-fi room in the space station is awesome. One of my saved references here for lighting in Unreal.

                              Comment


                                hi all.

                                i get an error using Luoshuang's GPU:

                                there are my Lightmass settings with traditional method (intensity 1, auto expurse)



                                if i use Deadalus51's settings (intensity 70.000 manual expurse, camera 100/125/14) i get all meshes black



                                if i use Deadalus51's settings with auto expurse (intensity 70.000 auto expurse but compensation using) i get correct interiors burning exteriros





                                it means Luoshuang's GPU have a bug with strong dome intensity?

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