Poser units and image texture sizes in Cycles



  • Going to call @trekkiegrrrl into this thread.

    Trekkie and I were working on some beta figure shaders. I was having a bit of a puzzle-solving time with image texture file sizes inside some Cycles shader nodes I was putting together. Trekkie meanwhile, had no issues. It turns out that Poser units in the Preferences section affects the image texture sizing. She was using nm, and I was using Poser default unit. So, I got to wondering how do character developers control for their character shader sets when end-users may be using different Poser units from the devs' installation.



  • @ibr_remote Of course, having said this, I do know that purely procedural shaders will solve the problem, but the issue of scale does exist. Not all end-users are experienced enough to be able to tweak node settings. Most folks prefer plug-and-play character sets.



  • @ibr_remote It's been my understanding that every translation channel value stored in Poser scene, character and pose, etc. files were in PNU and display in orange in the Parameters palette. Rotations are obviously in degrees (and display in yellow), while scales are scalar (unitless), and display in green. Certain camera parameters, such as Focal Length, display in white (as do all other parameters, which save to file without unit conversion), but have a specific unit displayed (mm in that case).

    There are no such obvious unit dependency features easily identifiable for shader node parameters. If they're not specifically listed in the manual, with unit preference selection behaviour described, then I think your best bet is to request such details from Smith Micro Support, so they can at least identify that there is a need to detail this information in manuals or elsewhere to avoid user confusion. The whole point of using internally consistent units for storage is that anyone loading such a scene will get the same results. If that is not the case, it's indicative of a bug and should be highlighted and reported as such.

    Do you have enough beta testers to cover different configuration scenarios?



  • @anomalaus thanks for responding - we're actually beta-ing the figure itself, and one of the ways is to see how it takes shaders from the 3 different root surfaces in Material Room. I understand your point about user-agnostic scaling, which ideally should be the case. However....



  • @ibr_remote ISTR that length measurements in "cycles" nodes are always in meters irrespective of your normal display unit, I am consistently wrong with such assumptions so your mileage may vary :)



  • Thing is, if you share the finished material as MC6 (I think they're called ...) - the units will change accordingly. If I make a skin material with a subsurface scattering of 2 mm and share that with someone using PNU, it will still look ok, even if the units MAY change.

    But copying screenshots of materials, then it becomes important to know which units was originally used, or it will come out differently.

    At least that's how I understand it.



  • @trekkiegrrrl said in Poser units and image texture sizes in Cycles:

    Thing is, if you share the finished material as MC6 (I think they're called ...) - the units will change accordingly. If I make a skin material with a subsurface scattering of 2 mm and share that with someone using PNU, it will still look ok, even if the units MAY change.

    But copying screenshots of materials, then it becomes important to know which units was originally used, or it will come out differently.

    At least that's how I understand it.

    That's why everyone should use inches, it's what @bagginsbill uses :o)



  • @amethystpendant said in Poser units and image texture sizes in Cycles:

    That's why everyone should use inches, it's what @bagginsbill uses :o)

    It is? I was pretty certain he said mm at some point. Anyway, I have no idea of inches. Means nothing to me, so I stick with metrics :)

    But it IS important to know what people are using if you copy their shaders from a screenshot (another reason why I so much prefer when people can actually share the file)



  • @amethystpendant hmmmm - I wasn't aware... 🤔🤔


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    @trekkiegrrrl said in Poser units and image texture sizes in Cycles:

    @amethystpendant said in Poser units and image texture sizes in Cycles:

    That's why everyone should use inches, it's what @bagginsbill uses :o)

    It is? I was pretty certain he said mm at some point. Anyway, I have no idea of inches. Means nothing to me, so I stick with metrics :)

    But it IS important to know what people are using if you copy their shaders from a screenshot (another reason why I so much prefer when people can actually share the file)

    I have always used inches because the material room internal unit (what is stored in material files regardless of the UI Poser Display Unit chosen) is inches and this way I can confirm the value I typed is the value I see in the mt5 file which I quite often have to reverse engineer, and because I'm an American. Just like you, I have no intuitive understanding of mm or cm. They are meaningless numbers to me.

    Most people do not know what ANY of the numbers in my shaders mean anyway so it makes little difference if you fail to understand the distances in them. Heheheh. Your job is to slavishly copy my screen shots. At Rendo, my posts had a signature reminding everybody my PDU is inches.



  • @bagginsbill said in Poser units and image texture sizes in Cycles:

    @trekkiegrrrl said in Poser units and image texture sizes in Cycles:

    @amethystpendant said in Poser units and image texture sizes in Cycles:

    That's why everyone should use inches, it's what @bagginsbill uses :o)

    It is? I was pretty certain he said mm at some point. Anyway, I have no idea of inches. Means nothing to me, so I stick with metrics :)

    But it IS important to know what people are using if you copy their shaders from a screenshot (another reason why I so much prefer when people can actually share the file)

    I have always used inches because the material room internal unit (what is stored in material files regardless of the UI Poser Display Unit chosen) is inches and this way I can confirm the value I typed is the value I see in the mt5 file which I quite often have to reverse engineer, and because I'm an American. Just like you, I have no intuitive understanding of mm or cm. They are meaningless numbers to me.

    Most people do not know what ANY of the numbers in my shaders mean anyway so it makes little difference if you fail to understand the distances in them. Heheheh. Your job is to slavishly copy my screen shots. At Rendo, my posts had a signature reminding everybody my PDU is inches.

    Interesting that Poser stores inches internally and not PNU. Oh well. Good to know that your units are inches. There's a pretty big difference between 5 inches and 5 mm :)


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    Funny thing is that SSS in the PhysicalSurface root node is set by mm.

    And the USA signed the metrical convention somewhere , oh boy, memory, around 1870? ? ?
    Wrong year for sure, but that century. LOL.



  • @vilters they also promised to spell Alumin(i)um and Sul(ph/f)ur correctly, but were foiled by the lowest common denominator problem. Cussedness and comprehension calculation: Take the maximum Ornery measurement and the lowest population IQ, confabulate and conflate them, then divide by the Population Agronomists' best guess at the population in 100 years time. That gives your chance that what you've written in Oxford (Oxfordshire, UK) English, will be understood without equivocation. The nearest unitary approximation is, of course, zero ;-)



  • @vilters said in Poser units and image texture sizes in Cycles:

    Funny thing is that SSS in the PhysicalSurface root node is set by mm.

    And the USA signed the metrical convention somewhere , oh boy, memory, around 1870? ? ?
    Wrong year for sure, but that century. LOL.

    I think it was ratified here in Denmark around the turn of the century. Still, my grandmother (born 1902) kept on talking, to her death more than 100 years later, about pounds (roughly ½ kg) and pots (which was roughly a liter) ... and yet we all knew what she meant ;)


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    Most of what was in the Metrical Convention is still in place, but a lot has been added to it since then.
    Now we have the International System of Units, which adds to that massively.
    The Commonwealth of Nations also standardized the Pound, the Yard, etc.

    All of that was brought about because there were too many different versions (actual weight or length) of the same wording which affected trade.


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    This is the video about the kg. (Unfortunately, until now, nobody knows what a kg is)
    Amerika on the metric system

    The kilogram is in trouble

    The worlds roundest object and how and why is the kg in trouble? => This video gives the origin and history.


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    Oddly, at 8:00 in the How we are redefining video, it sums it all up. Even with all that technology, what weighs exactly one KG today, won't tomorrow....


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    @shvrdavid
    Funny huh?
    We are end of 2018 and still not sure about the weight of the kg.
    LOL.

    Well, simply : The "master" obj in the vault in Paris "is" THE Kilogram even if it changes weight over time.