Carrara 8.5 Fast Mip Map DEGRADES all texture maps!
The images below is a simple example of the differences between Fast Mip Map and Sampling Filtering for textures in Carrara 8.5.
The phone box on the left uses Fast Mip Map and the one on the right uses Sampling.
The phone box on the right (in the Top image) has much more detail and in particular the text is much clearer and sharper.
To get both phone boxes to appear the same, the Object Accuracy must be set to .5 pixels in the render settings. With this setting there appears to be little difference between the two instances of the phone box (second image), although I think the phone box with Sampling still looks slightly better. However, even this simple example took 3 times as long to render (less than 1 second with the default Object Accuracy of 2 pixels and more than 3 seconds with the .5 setting).
I can only imagine (and shudder) at how much longer a complicated scene will take to render with this setting.
It seems ridiculous to have to increase render times this much just to get the same results with Fast Mip Map that we can get just by using Sampling.
As Fast Mip Map is now the default setting for C8.5, we will now be forced to choose between outrageously increased render times or the hours it will take to change all the shader elements from Fast Mip Map to Sampling by “hand”.
I think it is imperative to be able to set a preference in C8.5 to choose between the two Filtering methods. Without this I feel that C8.5 will be very difficult to use effectively.
Comments
oh oh, thanks for pointing this out
so does this setting come in at a certain range or is it all the time?
headwax said:
oh oh, thanks for pointing this out
so does this setting come in at a certain range or is it all the time?
headwax,
I am not sure what you mean regarding the setting? Would you mind giving me a little more detail?
Thanks
greetings Kakman :)
Ahh I've bought 8.5 but am just lurking watching the carnage , so am not using it as I really can't afford a screw up like s/numbers timing out etc. Or having textures degraded ....
My question.... I was under impressiion that mip mapping cliucked in when an object was a certain distance from the camera - to save resouces etc. But from what I can see this is not necessarily the case in your pic. ? Your pic indicates that it is degrading the texture regardless of distance from camera?
maybe I have the horse by the mouth ? :)
Hey headwax,
The Fast Mip Map problems certainly become more obvious as the distance increases. In fact "seams" begin to appear in a great many skin textures as the character is moved further from the camera.
I have found, now that I am experimenting with a large variety of models (clothing, buildings, props, etc.) that the degradation becomes quite noticeable regardless of the distance.
I find the whole application of the Fast Mip Map to be spurious regardless of the placement of the model.
I know that most times I want the appropriate details to be rendered for all the objects in a scene, not just the close-up ones.
I would like the choice in general/application preferences to chose default map type too.
Mostly for some C8.5 saved stuff I wish to open in C8.1
and if not using Genesis I frequently do so for many reasons.
not the least being you can have multiple instances of C8.1 open whist rendering!! C8.5 does not like this much.
Where you'll really notice a difference - but this also applies to Sampling as well, is this:
Set it at .5 object and shadow accuracy
Close in on the subject with the camera. Perhaps even too close
Render and observe render time
Leave the settings the same and the entire scene the same, but back off away from the subject without bringing anything new into the scene in front of the subject - obviously we'll be getting more of the surroundings
Now we can see the entire figure off into the scene - just a small fraction of the scene
Render
The scene still has the same texture to calculate, but can render out the subject with much few pixels
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I have my Rosie model that I've been working with forever now. She can really slow down renders when brought close to the camera, mostly because of her hair, which I've discovered (by removing them in a test) is mostly because of the alpha maps. But Carrara can really work them out with the camera backed off a little - but that has nothing to do with the Mip Map thing being degraded.
This is a very interesting discovery.
Personally, I don't know the facts about Fast Mip Map technology. The most I've heard, but I cannot remember the specifics, was said by Kevin Sanderson.
Do you think Fenric's Shader Tool would let you switch filter type across the board?
Speaking of Fenric, if you read this, is there any way you could sell your new plugins here as a bundled pack or something?
Somehow I cannot buy them now. Can't remember what the issue was - but I really would love to have them.
Fenric's Shader Doctor would be the perfect tool to address this (assuming the Carrara devs don't release a corrected update that allows this preference first, but I'm betting Fenric could put it together much faster).
There was an announcement he made over on the Carrara Cafe a couple of days ago that he was going to be updating the Shader Doctor to include 'Skin Doctor', which I am wildly excited about, as it will allow for a one click solution to make Poser material settings turn into Carrara friendly skin settings. I think that something like Carrara Skin Doctor ought to be something DAZ wants to sell in their store.
The picture example he gave of four different textures before and after, looked really great, and this could be a really important plugin tool for Carrara, equal to how important SkinVue is for Vue, so I hope he releases it soon and makes some good profit, as he deserves :)
But on topic, I'm not a programmer, and I'm betting Fenric himself could comment on it, but it seems like adding a function in Shader Doctor to automatically switch all selected shaders texture maps from mip map to sampling would be right in line with Shader Doctor.
He might not see this thread though...
An interesting discovery – yes!
I just do not understand why such a decision was made. Carrara is supposed to provide high quality renders, so I am confused why anyone at DAZ wants to force me to choose between rendering a lower quality image or investing excessive hours in render time or texture editing to get the high quality renders that I was used to getting with C8.1.
I think as more people begin to see the deleterious effect that the Fast Mip Map has on the details of various objects in their final renders and how much time and effort it takes to correct it, they will be as aghast as I am.
The degradation becomes very obvious on shingle roofs, and anything with stones and grout in it. Clock faces become blurry as does text. And it doesn’t just affect things in the distance either as the phone box images I have posted demonstrate.
I am hoping that the great PhilW chimes in on this, especially since he has put in so much time and effort with the whole gamma correction thing in an effort to get the most realistic renders ever.
And keep in mind that as the images get displayed on bigger screens with better resolution the effect becomes more pronounced.
I have found that in many instances the Fast Mip Map makes an object look as if it is slightly out of focus.
I had exactly the same thought as you Jonstark (and Dartanbeck as well) regarding having Fenric come to the rescue, but I feel it is incumbent upon DAZ to correct this issue in C8.5.
I just do not think they should have made this release of Carrara less effective than the previous versions.
I 100% agree that DAZ should correct this, but I have more faith in Fenric to be able to more quickly provide a workable solution then that the Carrara devs will be able to release an 8.5.2 addressing this in a timely fashion :) But I do agree that this is a problem that should be incumbent on DAZ to fix. Wonder what the appeal of adding mip maps in was anyway?
I 100% agree that DAZ should correct this, but I have more faith in Fenric to be able to more quickly provide a workable solution then that the Carrara devs will be able to release an 8.5.2 addressing this in a timely fashion :) But I do agree that this is a problem that should be incumbent on DAZ to fix. Wonder what the appeal of adding mip maps in was anyway?
Yes, we certainly do not want to be awaiting a "DAZ soon fix" - I am not sure that I have all that many years left to wait.
I too have faith that Fenric could make a fix that works, possibly as an addition to the already fantastic Shader Doctor.
If he can provide it, I will buy it! (As I have with all his other products).
It is strange that they chose this as the default.
I would also like to see this in preferences or handled in some way that doesn't involve manually changing shaders. This sort of thing makes me feel somewhat better about my decision to skip this upgrade.
In case it hasn't been mentioned yet: it's probably easier to change the filtering in bulk using a text editor. Just decompress the files first if necessary (cbr files appear to be compressed).
I don't know exactly what needs to be changed, but it shouldn't be too hard to figure out. "Filt" is a likely candidate.
Edited to add that there are programs with which you can easily edit a whole bunch of files in one go. Like this for example:
http://stefanstools.sourceforge.net/grepWin.html
FYI,
I sent Fenric a PM through the system here to see if he would be interested in (and able to) add this to the
forthcoming Shader Doctor update.
Thanks Kakman, I should have thought of that. Maybe he'll weigh in and let us know what's possible.
And besides, he might let us know when this new Skin Doctor might be released. Although I think he should call it SkinCarrara. If Vue gets a SkinVue, we should get a SkinCarrara. :)
that title brings up some scary flaying images in my mind! :vampire:
Sorry to butt in, but maybe I can shed a tiny beam of light on the subject...
The PURPOSE of Fast Mip Map is to degrade texture maps. :)
It's kinda like the Carrara LOD (?) feature, which generates low rez versions of high rez stuff for a specific purpose. LOD uses low poly stand-in objects for a specific purpose. Likewise, with mip mapped textures it generates low rez "stand-in" versions of the texture in order to speed up rendering. Since you don't need high rez textures for stuff that is far away from the camera, you substitute the high rez texture with the low rez texture on those objects (depending upon distance), and that allows the renderer to calculate less pixels and therefore speeds it up.
The cost of all of this is increase memory and storage space required for those additional textures that are generated. Don't recall exactly how much, but I do recall it isn't nearly as much as I thought.
So the question becomes, does Carrara use high enough rez textures at a given distance? Well, it's a tradeoff. If you put the same rez textures at the same distance as a different method, then you ain't gonna gain much in terms of render speed, and you've defeated your whole purpose... :)
So it's kinda like, by definition, if you do a side by side comparison of mipmapped vs. another method at the same distance, you'd expect that the mipmapped texture might not look as clear. It's a good thing, and that's what it's designed for. Though you hope it's not too noticeable, but unfortunately with sharp lines as in text it is a bit more obvious. But it's all a tradeoff....no right answer, just what seems reasonable.
And keep in mind that resolution varies by distance, but since there are only a certain (limited) number of low rez textures generated, it might abruptly switch to a different rez texture as you change distance. And I imagine only the programmers know exactly which resolution texture kicks in at what distance.....
I presume that DAZ decided that the average user was far more interested in render speed than clarity of textures in the renders, and therefore chose that default.
But I do agree that, in terms of settable preferences, Carrara has a whole ton of things that SHOULD BE settable preferences, and this certainly fits the bill. On the other hand, then you'll need to ask yourself if you REALLY want to give up the rendering speed associated with fast mip map in favor of a (somewhat?/slightly?) clearer render......
Your uv-mapped object is not going to have a 1:1 relationship between pixels in the texture map and final pixels in your rendered image. As the renderer selects which ones to use, it frequently must decide what to do in two situations:
1 - when the final pixel corresponds to multiple UV coordinates on the object
2 - when a UV coordinate ends in-between pixels on the texture map
The first situation is a problem when detailed textures are rendered at a distance from the camera: the result all too often will have characteristic "swirls" or "phantom lines" appear known as Moire patterns. Fast Mip-Map is intended to reduce these by pre-reducing the texture resolution and removing fine details (it isn't really about render performance). It can make scenes with a large depth of field look considerably better. Sparrowhawke has had a plugin shader to do this for a long time now.
Choosing Mip-Map for the default filtering method was not the choice I would have made, but it is hardly unusual: Poser's default "Quality" texture filtering does the same thing (and has similar undesirable side effects). Of course, in Poser there are several Python scripts to choose from that fix it.
For objects that are closer to the camera, the second situation comes into play.
Sampling is the same as Poser "None" filtering - it simply chooses the nearest available pixel from the texture map and uses it regardless of how correct or incorrect that may be. It will give better results than mip-map for intermediate distance objects, but may cause moire patterns in distant objects and a distinct digital-looking blockiness for close-up objects.
For best close-up results in Carrara, you really want "Gaussian Filtering" which will interpolate between texture-map pixels to get the closest possible result. (I wouldn't bother with Box Filtering).
And yes, I agree that Carrara does need a way to change blocks of texture maps all at once. I'm already looking at it, I just haven't yet figured out how to access the parameters of the texture-map shader: it's not documented and what I've seen so far doesn't quite match how most other things in Carrara seem to work. I don't want to hold up my Shader Doctor update - I just finished the release candidate Mac builds - so it's not going to be bundled in there.
Yep, most good animation packages have Fast Mip-Map or a variation. It helps reduce crawling dots, moire, etc. There's a DAZ Studio user who always complains about the 3Delight version (tdlmake), but ignores that 3Delight is designed for motion picture work where it's very much wanted and needed. DAZ probably should've made it so it could be switched on in Carrara as some users probably won't want it since they are under the mistaken idea that everything CG should be sharp as a tack - it shouldn't be that sharp if you are striving for photo realism.
Which brings us to my oft repeated question, if that's the purpose of FastMipMap then why would they EVER sell Elite Skin Maps where everything was set to FastMipMap? So that to get a quality render you have to go in and change the texture setting for every single body part with a shader???? The Elite Skins are supposed to be the best for high quality work, or at least that is what Daz sells them as. So why would they deliberately degrade the quality of their high quality textures?
Boojum the brown bunny
I have a feeling that the answer to this:
Yep, most good animation packages have Fast Mip-Map or a variation. It helps reduce crawling dots, moire, etc. There's a DAZ Studio user who always complains about the 3Delight version (tdlmake), but ignores that 3Delight is designed for motion picture work where it's very much wanted and needed. DAZ probably should've made it so it could be switched on in Carrara as some users probably won't want it since they are under the mistaken idea that everything CG should be sharp as a tack - it shouldn't be that sharp if you are striving for photo realism.
And that the Fast Mip Map(as it's introduction into Carrara) utilizes its method to really show off the super details when needed up close, and not dragging down the render times when such high clarity is not necessary. Sort of like reducing or even, perhaps eliminating the urge or need to use blurred reflections - as the Mip Map helps to remove the sharpness.
I remember a time when I used to use unsharp mask for everything! Much like what Kevin says above. I look at a lot of my old 'sharpened' images now with agony.
But it leaves your character look like it's been chopped up and put back together if you view the whole figure. You end up with lines between every UV map on the figure. I don't agree that you would, by default, set your most photorealistic shaders to a setting that would make it unusable in a full body render. Instead, you would set it to be photorealistic and then let people change it to fastmipmap if they need speed.
Boojum the brown bunny
Yep, most good animation packages have Fast Mip-Map or a variation. It helps reduce crawling dots, moire, etc. There's a DAZ Studio user who always complains about the 3Delight version (tdlmake), but ignores that 3Delight is designed for motion picture work where it's very much wanted and needed. DAZ probably should've made it so it could be switched on in Carrara as some users probably won't want it since they are under the mistaken idea that everything CG should be sharp as a tack - it shouldn't be that sharp if you are striving for photo realism.
Do most of these “good animation packages” that have Fast Mip Map force this upon the user as the default with no way to change it either as a an overall choice or on a scene by scene basis (which I think would be preferred)?
Do these other software packages have to ability to change the texture filtering on an item by item basis (which I think is sorely needed)?
Do these other software packages cause seems to appear in figures when they employ the Fast Mip Map setting? I do not think that having white seams appear on human figures (on various body areas) in the distance is very photo-realistic.
What if I am not striving for photo realism – which is often the case? The way it is now I would have to spend hours changing hundreds of shaders to get the effect that I want.
I have not had a whole lot of time to experiment and analyze all the effects that the Fast Mip Map filtering has at this point, but it seems that once I set the Object Accuracy to .5 pixels it eliminates the degradation effect regardless of the distance the object is from the camera (not positive on this one yet). And an Object Accuracy setting of .5 pixels is used quite often from what I can glean from various postings in this forum.
I think it is all about having a choice on when and where a user might want to utilize various filtering choices without creating a huge time suck to do so.
I certainly want to be able to make the choice between quality and speed and If I choose quality I do not want to be penalized by having to spend hours and hours changing hundreds of textures.
Thank you so very much Fenric for considering to try and provide a workable solution for this. I still can not fathom why DAZ would have forced the Fast Mip Map Filtering on the Carrara users as a default without an alternative. And I really can not understand why this change and the effects that it has (and how extremely different it is compared to past versions) wasn't pointed out in DETAIL.
Kakman, I'm curious about why this wasn't noticed by those folks who used the beta. I didn't so I can't check on what you are finding. I'm still waiting on a check to arrive so I can buy 8.5 while it's still on sale.
I agree, you shouldn't be seeing seems - the purpose is to try to reduce artifacts. And they probably should have made it an option. (I wouldn't be surprised there's some setting or combination we don't know we should use.) However, in 3Delight it's default (as tdlmake) with filters provided to adjust the blur/sharpness, but I don't think I've ever seen seems in 3Delight renders. I've only seen complaints about lack of sharpness from folks who don't change the filter settings in Studio/3Delight. In messiah, it's an anti-alias option that was added in v5. Other packages have it, too, but I don't know their specifics.
Kevin,
I can only answer for myself regarding the use of the Beta. I only used the Beta for “playing around with the Genesis items” not for the production of any final work.
In my experience there were so many things that did not work in the Beta that I did not consider the state it was in to be a serious release candidate.
DAZ had stated that they were aware of many of the issues and were fixing them for the C8.5 release. There were so many issues that I decided to wait for the release candidate and then see what was what.
I will point out that a long time complaint with the Texture Filter default, from a significant number of customers, is that Texture Filter blurs the texture and makes it not suitable for closeups. Fast Mip-Map was designed to give you the better resolution for closeups without sacrificing speed, and most of you also care about speed.
The problem with the seam lines showing up goes away, in most cases, by getting a little further and/or a little closer to the subject. (Usually only a nudge.) Carrara doesn't have an equivalent to shading rate that you have in DS or Poser, and setting that at 1 in either DS or Poser gives you the same results you are seeing in Carrara with Poser/DS Content, and since the content with the issue was designed for those render engines....
Actually, the problem with the seams gets worse the farther away you get. they actually get bigger!
boojum