Why do different render engines generate different z pass?Cycles generates distorted depthPrecision of Z-coordinateMake an object's visibility controlled by another object or an emptyCreating depth of field from Beauty+Depth passes (rendered in another software)data formatting of Z-bufferIs it possible to create a render layer with no depth of field?Z-Buffer rendering issuesHow to get the right values for Z depth renderingDepth in meters for rendered imagesUninterpretablity in depth maps: why the pixel values do not necessarily represent a valid distance?Z-Buffer render gives unexpected resultsCycles generates distorted depthRendering depth map that is linear, aliased, normalized

How can I write humor as character trait?

How do you make your own symbol when Detexify fails?

Angel of Condemnation - Exile creature with second ability

Does the Linux kernel need a file system to run?

Has any country ever had 2 former presidents in jail simultaneously?

Can a college of swords bard use blade flourish on an OA from dissonant whispers?

Mimic lecturing on blackboard, facing audience

Does an advisor owe his/her student anything? Will an advisor keep a PhD student only out of pity?

When were female captains banned from Starfleet?

Isn't the "if" redundant here?

Open a doc from terminal, but not by its name

It grows, but water kills it

Why does a simple loop result in ASYNC_NETWORK_IO waits?

Fear of getting stuck on one programming language / technology that is not used in my country

A binary search solution to 3Sum

How to cover method return statement in Apex Class?

Is there a RAID 0 Equivalent for RAM?

What is going on with 'gets(stdin)' on the site coderbyte?

Why did the EU agree to delay the Brexit deadline?

How do apertures which seem too large to physically fit work?

Make a Bowl of Alphabet Soup

Yosemite Fire Rings - What to Expect?

Why is it that I can sometimes guess the next note?

How to align my equation to left?



Why do different render engines generate different z pass?


Cycles generates distorted depthPrecision of Z-coordinateMake an object's visibility controlled by another object or an emptyCreating depth of field from Beauty+Depth passes (rendered in another software)data formatting of Z-bufferIs it possible to create a render layer with no depth of field?Z-Buffer rendering issuesHow to get the right values for Z depth renderingDepth in meters for rendered imagesUninterpretablity in depth maps: why the pixel values do not necessarily represent a valid distance?Z-Buffer render gives unexpected resultsCycles generates distorted depthRendering depth map that is linear, aliased, normalized













5












$begingroup$


I've been using Blender to generate depth maps using z pass. I notice that the z pass generated by different render engines are different, which made me a bit confused. My feeling is that the z pass generated by Cycle render denotes distance from a given pixel to the camera center while Blender render generates an orthogonal distance to the camera plane. Do I understand it correctly? Is so, is there a way to change such behavior for both render modes?



As an example, the bottom area of the model is a flat surface, to which the camera is perpendicularly pointed. Below are the nodes I use to normalize and visualize the z pass data (Viewer node is used to save the depth map).



Nodes to normalize and view



Z pass with Cycles render:



Z pass with Cycles render



Z pass with blender render (everywhere same value in the bottom part):



Z pass with blender render










share|improve this question









$endgroup$











  • $begingroup$
    Read this related link: Precision of z coordinate
    $endgroup$
    – cegaton
    Mar 12 at 17:54










  • $begingroup$
    Also related: Cycles generates distorted depth
    $endgroup$
    – cegaton
    Mar 12 at 17:57















5












$begingroup$


I've been using Blender to generate depth maps using z pass. I notice that the z pass generated by different render engines are different, which made me a bit confused. My feeling is that the z pass generated by Cycle render denotes distance from a given pixel to the camera center while Blender render generates an orthogonal distance to the camera plane. Do I understand it correctly? Is so, is there a way to change such behavior for both render modes?



As an example, the bottom area of the model is a flat surface, to which the camera is perpendicularly pointed. Below are the nodes I use to normalize and visualize the z pass data (Viewer node is used to save the depth map).



Nodes to normalize and view



Z pass with Cycles render:



Z pass with Cycles render



Z pass with blender render (everywhere same value in the bottom part):



Z pass with blender render










share|improve this question









$endgroup$











  • $begingroup$
    Read this related link: Precision of z coordinate
    $endgroup$
    – cegaton
    Mar 12 at 17:54










  • $begingroup$
    Also related: Cycles generates distorted depth
    $endgroup$
    – cegaton
    Mar 12 at 17:57













5












5








5





$begingroup$


I've been using Blender to generate depth maps using z pass. I notice that the z pass generated by different render engines are different, which made me a bit confused. My feeling is that the z pass generated by Cycle render denotes distance from a given pixel to the camera center while Blender render generates an orthogonal distance to the camera plane. Do I understand it correctly? Is so, is there a way to change such behavior for both render modes?



As an example, the bottom area of the model is a flat surface, to which the camera is perpendicularly pointed. Below are the nodes I use to normalize and visualize the z pass data (Viewer node is used to save the depth map).



Nodes to normalize and view



Z pass with Cycles render:



Z pass with Cycles render



Z pass with blender render (everywhere same value in the bottom part):



Z pass with blender render










share|improve this question









$endgroup$




I've been using Blender to generate depth maps using z pass. I notice that the z pass generated by different render engines are different, which made me a bit confused. My feeling is that the z pass generated by Cycle render denotes distance from a given pixel to the camera center while Blender render generates an orthogonal distance to the camera plane. Do I understand it correctly? Is so, is there a way to change such behavior for both render modes?



As an example, the bottom area of the model is a flat surface, to which the camera is perpendicularly pointed. Below are the nodes I use to normalize and visualize the z pass data (Viewer node is used to save the depth map).



Nodes to normalize and view



Z pass with Cycles render:



Z pass with Cycles render



Z pass with blender render (everywhere same value in the bottom part):



Z pass with blender render







cycles rendering blender-render render-passes






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked Mar 12 at 16:12









DingLuoDingLuo

263




263











  • $begingroup$
    Read this related link: Precision of z coordinate
    $endgroup$
    – cegaton
    Mar 12 at 17:54










  • $begingroup$
    Also related: Cycles generates distorted depth
    $endgroup$
    – cegaton
    Mar 12 at 17:57
















  • $begingroup$
    Read this related link: Precision of z coordinate
    $endgroup$
    – cegaton
    Mar 12 at 17:54










  • $begingroup$
    Also related: Cycles generates distorted depth
    $endgroup$
    – cegaton
    Mar 12 at 17:57















$begingroup$
Read this related link: Precision of z coordinate
$endgroup$
– cegaton
Mar 12 at 17:54




$begingroup$
Read this related link: Precision of z coordinate
$endgroup$
– cegaton
Mar 12 at 17:54












$begingroup$
Also related: Cycles generates distorted depth
$endgroup$
– cegaton
Mar 12 at 17:57




$begingroup$
Also related: Cycles generates distorted depth
$endgroup$
– cegaton
Mar 12 at 17:57










1 Answer
1






active

oldest

votes


















3












$begingroup$

When rendering a Z pass you are essentially creating a depth map from the camera point of view. The issue here is there is potentially infinite range of distances to represent by colors and only 256 shades of gray available to map them to, in a traditional 8 bit image you have .



It can go from zero close to the camera (unlikely there is something this close) to whichever visible object is most most distant. But there may also be a sky or "background" at a theoretical infinite distance.



There are several possible ways to map these shades of grey to the distance progression each with its own advantages.



It can be a linear mapping where detail is distributed evenly across all image, but here may also be logarithmic mappings, emphasizing detail at certain parts of the picture.



  • You may want more detail at close range where image focus is likely to reside.

  • The scene may require more detail at large distances if you are rendering a landscape or distant view

  • You may want to use it for a mist pass requiring details at a medium range.

As far as I know would expect both Cycles and Blender Render to use the same "true distance to sensor", not a virtual orthographic plane passing through the sensor, but I may be wrong.



If that is indeed the case or you require a specific color progression or custom mapping of values you may construct your own "an artificial Z pass".



You can do so by making a basic emission shader with a circular black to white gradient mapped to the camera object.



Moving the camera should update the position. You can scale the gradient as desired to accommodate your desired distance range, and drive it through a Color Ramp for a non linear progression.






share|improve this answer











$endgroup$












    Your Answer





    StackExchange.ifUsing("editor", function ()
    return StackExchange.using("mathjaxEditing", function ()
    StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix)
    StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
    );
    );
    , "mathjax-editing");

    StackExchange.ready(function()
    var channelOptions =
    tags: "".split(" "),
    id: "502"
    ;
    initTagRenderer("".split(" "), "".split(" "), channelOptions);

    StackExchange.using("externalEditor", function()
    // Have to fire editor after snippets, if snippets enabled
    if (StackExchange.settings.snippets.snippetsEnabled)
    StackExchange.using("snippets", function()
    createEditor();
    );

    else
    createEditor();

    );

    function createEditor()
    StackExchange.prepareEditor(
    heartbeatType: 'answer',
    autoActivateHeartbeat: false,
    convertImagesToLinks: false,
    noModals: true,
    showLowRepImageUploadWarning: true,
    reputationToPostImages: null,
    bindNavPrevention: true,
    postfix: "",
    imageUploader:
    brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
    contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
    allowUrls: true
    ,
    onDemand: true,
    discardSelector: ".discard-answer"
    ,immediatelyShowMarkdownHelp:true
    );



    );













    draft saved

    draft discarded


















    StackExchange.ready(
    function ()
    StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fblender.stackexchange.com%2fquestions%2f134122%2fwhy-do-different-render-engines-generate-different-z-pass%23new-answer', 'question_page');

    );

    Post as a guest















    Required, but never shown

























    1 Answer
    1






    active

    oldest

    votes








    1 Answer
    1






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes









    3












    $begingroup$

    When rendering a Z pass you are essentially creating a depth map from the camera point of view. The issue here is there is potentially infinite range of distances to represent by colors and only 256 shades of gray available to map them to, in a traditional 8 bit image you have .



    It can go from zero close to the camera (unlikely there is something this close) to whichever visible object is most most distant. But there may also be a sky or "background" at a theoretical infinite distance.



    There are several possible ways to map these shades of grey to the distance progression each with its own advantages.



    It can be a linear mapping where detail is distributed evenly across all image, but here may also be logarithmic mappings, emphasizing detail at certain parts of the picture.



    • You may want more detail at close range where image focus is likely to reside.

    • The scene may require more detail at large distances if you are rendering a landscape or distant view

    • You may want to use it for a mist pass requiring details at a medium range.

    As far as I know would expect both Cycles and Blender Render to use the same "true distance to sensor", not a virtual orthographic plane passing through the sensor, but I may be wrong.



    If that is indeed the case or you require a specific color progression or custom mapping of values you may construct your own "an artificial Z pass".



    You can do so by making a basic emission shader with a circular black to white gradient mapped to the camera object.



    Moving the camera should update the position. You can scale the gradient as desired to accommodate your desired distance range, and drive it through a Color Ramp for a non linear progression.






    share|improve this answer











    $endgroup$

















      3












      $begingroup$

      When rendering a Z pass you are essentially creating a depth map from the camera point of view. The issue here is there is potentially infinite range of distances to represent by colors and only 256 shades of gray available to map them to, in a traditional 8 bit image you have .



      It can go from zero close to the camera (unlikely there is something this close) to whichever visible object is most most distant. But there may also be a sky or "background" at a theoretical infinite distance.



      There are several possible ways to map these shades of grey to the distance progression each with its own advantages.



      It can be a linear mapping where detail is distributed evenly across all image, but here may also be logarithmic mappings, emphasizing detail at certain parts of the picture.



      • You may want more detail at close range where image focus is likely to reside.

      • The scene may require more detail at large distances if you are rendering a landscape or distant view

      • You may want to use it for a mist pass requiring details at a medium range.

      As far as I know would expect both Cycles and Blender Render to use the same "true distance to sensor", not a virtual orthographic plane passing through the sensor, but I may be wrong.



      If that is indeed the case or you require a specific color progression or custom mapping of values you may construct your own "an artificial Z pass".



      You can do so by making a basic emission shader with a circular black to white gradient mapped to the camera object.



      Moving the camera should update the position. You can scale the gradient as desired to accommodate your desired distance range, and drive it through a Color Ramp for a non linear progression.






      share|improve this answer











      $endgroup$















        3












        3








        3





        $begingroup$

        When rendering a Z pass you are essentially creating a depth map from the camera point of view. The issue here is there is potentially infinite range of distances to represent by colors and only 256 shades of gray available to map them to, in a traditional 8 bit image you have .



        It can go from zero close to the camera (unlikely there is something this close) to whichever visible object is most most distant. But there may also be a sky or "background" at a theoretical infinite distance.



        There are several possible ways to map these shades of grey to the distance progression each with its own advantages.



        It can be a linear mapping where detail is distributed evenly across all image, but here may also be logarithmic mappings, emphasizing detail at certain parts of the picture.



        • You may want more detail at close range where image focus is likely to reside.

        • The scene may require more detail at large distances if you are rendering a landscape or distant view

        • You may want to use it for a mist pass requiring details at a medium range.

        As far as I know would expect both Cycles and Blender Render to use the same "true distance to sensor", not a virtual orthographic plane passing through the sensor, but I may be wrong.



        If that is indeed the case or you require a specific color progression or custom mapping of values you may construct your own "an artificial Z pass".



        You can do so by making a basic emission shader with a circular black to white gradient mapped to the camera object.



        Moving the camera should update the position. You can scale the gradient as desired to accommodate your desired distance range, and drive it through a Color Ramp for a non linear progression.






        share|improve this answer











        $endgroup$



        When rendering a Z pass you are essentially creating a depth map from the camera point of view. The issue here is there is potentially infinite range of distances to represent by colors and only 256 shades of gray available to map them to, in a traditional 8 bit image you have .



        It can go from zero close to the camera (unlikely there is something this close) to whichever visible object is most most distant. But there may also be a sky or "background" at a theoretical infinite distance.



        There are several possible ways to map these shades of grey to the distance progression each with its own advantages.



        It can be a linear mapping where detail is distributed evenly across all image, but here may also be logarithmic mappings, emphasizing detail at certain parts of the picture.



        • You may want more detail at close range where image focus is likely to reside.

        • The scene may require more detail at large distances if you are rendering a landscape or distant view

        • You may want to use it for a mist pass requiring details at a medium range.

        As far as I know would expect both Cycles and Blender Render to use the same "true distance to sensor", not a virtual orthographic plane passing through the sensor, but I may be wrong.



        If that is indeed the case or you require a specific color progression or custom mapping of values you may construct your own "an artificial Z pass".



        You can do so by making a basic emission shader with a circular black to white gradient mapped to the camera object.



        Moving the camera should update the position. You can scale the gradient as desired to accommodate your desired distance range, and drive it through a Color Ramp for a non linear progression.







        share|improve this answer














        share|improve this answer



        share|improve this answer








        edited Mar 12 at 18:22

























        answered Mar 12 at 16:58









        Duarte Farrajota RamosDuarte Farrajota Ramos

        34.1k53981




        34.1k53981



























            draft saved

            draft discarded
















































            Thanks for contributing an answer to Blender Stack Exchange!


            • Please be sure to answer the question. Provide details and share your research!

            But avoid


            • Asking for help, clarification, or responding to other answers.

            • Making statements based on opinion; back them up with references or personal experience.

            Use MathJax to format equations. MathJax reference.


            To learn more, see our tips on writing great answers.




            draft saved


            draft discarded














            StackExchange.ready(
            function ()
            StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fblender.stackexchange.com%2fquestions%2f134122%2fwhy-do-different-render-engines-generate-different-z-pass%23new-answer', 'question_page');

            );

            Post as a guest















            Required, but never shown





















































            Required, but never shown














            Required, but never shown












            Required, but never shown







            Required, but never shown

































            Required, but never shown














            Required, but never shown












            Required, but never shown







            Required, but never shown







            -blender-render, cycles, render-passes, rendering

            Popular posts from this blog

            Word for a person who has no opinion about whether god existsWord for having a definite opinion while simultaneously withholding judgment?What's the opposite of “newcomer? Is ”veteran" OK?What do you call an “atheist” who might believe in an afterlife?What's a word for someone who wants to voice opinions but not have them challenged?Word for someone who dismisses contrary opinions as irrational?Somone who thinks they are overly special/out of the ordinaryIs there a word, phrase or idiom for “a person who is incapable of thinking about the future”?The belief that a god is human-likeA word for a non-famous person/thing you have heard a lot aboutAdjective for a person who enjoys taking care of their appearance

            2017 IndyCar Series Contents Series news Teams and drivers Schedule Season summary Footnotes References External links Navigation menu"INDYCAR: Initial 2018 bodywork concepts unveiled"the original"IndyCar confirms switch to Performance Friction brakes in 2017""AJ Foyt Racing will switch to Chevy"the original"Carlos Munoz, Conor Daly will drive for AJ Foyt Racing""Zach Veach's Indy 500 Debut Confirmed with Foyt""No mass exodus from Honda after Ganassi switch""Ex-F1 driver Sato joins Andretti Autosport for 2017 IndyCar season""IndyCar's Ryan Hunter-Reay, sponsor DHL paired through 2020""hhgregg and Andretti Autosport announce partnership for key races in 2016""INDYCAR: Rossi re-signs with Andretti"the original"McLaren Formula 1 - Fernando Alonso to race at Indy 500 with McLaren, Honda and Andretti Autosport""Shank will finally take part in Indy 500 with Harvey, Andretti | MotorSportsTalk""Andretti adds Jack Harvey to Indy 500 field""Ganassi switches to Honda power for 2017""INDYCAR: Chilton returns to Ganassi"the original"IndyCar silly season: Who's going where in 2017?""INDYCAR: Kanaan, NTT Data return to Ganassi"the original"Kimball to remain at Ganassi for 2017""Coyne confirms Bourdais for 2017 IndyCar season""Davison to sub for Bourdais in Indy 500"the original"Gutierrez confirmed for Detroit IndyCar debut""Gutierrez returns with Coyne for rest of 2017 season""Vautier to drive for Coyne at Texas"the original"INDYCAR: Coyne confirms Jones for 2017"the original"Pippa Mann returns to Coyne for Indy 500""Karam, Dreyer & Reinbold teaming up again for Indianapolis 500""Pigot to return to Ed Carpenter Racing""Hildebrand confirmed as full-time Ed Carpenter driver""Veach to replace injured Hildebrand at Barber"the originalNew Team Harding Racing Enters Chaves for 101st Indianapolis 500"Juncos Racing Announces Entry in 101st Running of the Indianapolis 500 :: Juncos Racing""Juncos confirms Pigot for Indy 500""Saavedra confirmed in Juncos' second 500 entry"the original"Lazier confirms Indy 500 run after son's USF2000 debut"the original"Claman DeMelo to race for RLLR at Sonoma"the original"Rahal signs Servia and ace engineer for 2017""IndyCar: Aleshin returns with Schmidt"the original"Aleshin replaced by Saavedra for Toronto""Jack Harvey will pilot SPM No. 7 car at Watkins Glen, Sonoma""Jay Howard confirmed in Tony Stewart's supported SPM Indy entry""INDYCAR: Newgarden to wave the flag at Penske"the original"Pagenaud opts for No. 1 in 2017"the original"Penske confirms Newgarden for 2017""Montoya to stay with Team Penske in 2017""Target leaving IndyCar after 27 seasons with Chip Ganassi""Cavin: IndyCar could see complete driver/team shakeup in 2017""End of the road for KV Racing?""KV Racing confirms closure, equipment sold to Juncos""Juncos confirms IndyCar Series entry"the original"Juncos readies IndyCar program, aims for '17 500"the original"Harding Racing to add Texas, Pocono to schedule"the original"Sato signs with Andretti Autosport for 2017""INDYCAR: Aleshin in Doubt at SPM"the original"Long Beach notebook: JR Hildebrand breaks hand""Hildebrand cleared to return at Phoenix"the original"Bourdais to undergo surgery on multiple fractures""Aleshin loses Schmidt Peterson IndyCar ride""Saavedra in at SPM for Pocono, Gateway"the original"Bourdais to make return at Gateway"the original"The IndyCar Grand Prix no longer is sponsored by Angie's List""2017 IndyCar Series rulebook""2017 Verizon IndyCar Series Official Rulebook"Official websiteeeeee

            What was this official D&D 3.5e Lovecraft-flavored rulebook?What was this set of RPG tools called?As a first-time DM should I let my players play complex character classes and roles?Nymph's Kiss and the RelationshipWhat was the name of this Cleric Prestige Class that shapes metal with its bare hands?Are the 3.5e Dragonlance books third party or official works?What's up with the domain Vile Darkness?What was this 80s book about RPGs?What was the name of this Werewolf band?What book had Rituals to “upgrade” animal companions to keep them viable at higher levels?What was this RPG that had rules for player-owned businesses?