How do I get a reasonable light? Less intense shadows?

tdrdtdrd Posts: 0
edited December 1969 in Bryce Discussion

I don't know about the rest of you, but I have muddled around with the sun in the sky settings and I cannot get a general light for daytime.

I'll digress... I move the sun so that there is normal daylight - say 3pm on a normal (for England) hazy sunny day.

Now in real terms this would mean that the front of the building (south facing) would get the full light and effect, and the shadows would not be as strong as those given by the software. Bryce seems to think of light as being ON or OFF - nothing in between.

I cannot find any way to have reasonably strong sunlight yet weak shadows. It's great for effect I suppose but realistically light is not just on or off. If I rotate the viewpoint to the rear of the building it is unrealistically dark - The shadows would never be that intense so that it's almost night.

So is there a way of controlling the intensity of the darkness given by shadows? I have a house with a porch and the shadows it's giving off are just too direct - you'd expect some light to hit the shaded area in some measure.

Thanks in advance for any feedback

Terry

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Comments

  • SzarkSzark Posts: 8,765
    edited September 2012

    Not sure why you posted this thread here in the Free Stuff/General Freepozitory section.


    Anyways in Bryce you have control over how intense shadows are in the Light Lab in the Sun section toward the bottom of the window.

    Another way is to add a Fill light coming from the opposite direction to the sun or just behind the camera at about 5% to lighten shadows or use True Ambience.

    This is an excellent learning resource for Bryce http://www.daz3d.com/forums/discussion/2839/

    Post edited by Szark on
  • FixmypcmikeFixmypcmike Posts: 11,685
    edited December 1969

    Moved to Bryce Discussion

  • tdrdtdrd Posts: 0
    edited December 1969

    I sincerely apologise for posting this in the wrong group.
    I had the two groups open in different windows and I guess I got it wrong.
    Many apologies.

  • GussNemoGussNemo Posts: 1,855
    edited December 1969

    @tdrd: You can also find several lighting tutorials here, http://www.bryce-tutorials.info/index.html . If you search You Tube you also find several on lighting.

  • Rashad CarterRashad Carter Posts: 1,034
    edited December 1969

    tdrd said:
    I don't know about the rest of you, but I have muddled around with the sun in the sky settings and I cannot get a general light for daytime.

    I'll digress... I move the sun so that there is normal daylight - say 3pm on a normal (for England) hazy sunny day.

    Now in real terms this would mean that the front of the building (south facing) would get the full light and effect, and the shadows would not be as strong as those given by the software. Bryce seems to think of light as being ON or OFF - nothing in between.

    I cannot find any way to have reasonably strong sunlight yet weak shadows. It's great for effect I suppose but realistically light is not just on or off. If I rotate the viewpoint to the rear of the building it is unrealistically dark - The shadows would never be that intense so that it's almost night.

    So is there a way of controlling the intensity of the darkness given by shadows? I have a house with a porch and the shadows it's giving off are just too direct - you'd expect some light to hit the shaded area in some measure.

    Thanks in advance for any feedback

    Terry


    To my thinking it is a mistake to think of Sunlight shadows as being too intense. Many Bryce users approach lighting in the wrong way and have earned Bryce the reputation for creating low contrast images because of lack of shadows. Instead of wondering why shadows are so intense, it is best to ask yourself where the light you'd expect to see in the shadows is actually coming from in real life. In real life the sun gives shadows 100% intensity, but the shadows are lightened by the indirect light scattered by the atmospheric gases and also from light bouncing off nearby surfaces such as the walls of a building or the ground plane. In a realistic render, the secret is interaction, and shadow casting is an important type of interaction. Shadows are not the enemy.

    You can always lower your shadow intensity in the Sky Lab. The Sun Shadow intensity slider is the reference for all other lights in the scene so if you lower the shadows of the sun to 50% then your radials will also have lowered shadows. This is one reason why I think it a major mistake in most situations to lessen shadow intensity for the Sun.

    There are two forms of light people need to be aware of...Direct illumination and Indirect illumination.

    Clearly and obviously the default sun and the standard point radial qualify as Direct or Key light sources. But for indirect light (which by the way is where the real realism occurs) is much trickier to make choices about.

    Several tools are available in Bryce to help with indirect lighting. First is the Material Ambience. Ambience from a material applies a uniform glow to an object that can help to raise the darkness of shadows to something less intense. But the trade off is that the object will have lowered bump contrast and other things. Plus if you use too much and sometimes even 10% is too much you can accidentally create a glowing object which gives the impression of thermal heat radiance (think hot coals), not what you would usually want. So use Material Ambience very sparingly if at all. I should also state that Material Ambience is governed by the color of the Ambience swatch in the Sky Lab. If you make this swatch black, no matter how high you set the ambience of a material it will not glow at all.

    Another Option is in the Sky Lab called Skydome. Skydome is basically a point radial positioned high above the Bryce world, shining light down directly onto the ground. The Skydome effect does not cast shadows so it cuts through solid surfaces which is physically inaccurate, because only those surfaces which face the sky directly such as rooftops and the ground plane are illuminated, vertical walls are left totally black. But Skydome is sometimes better than nothing. For me and my lean toward realism, I dont use Material Ambience nor the Skydome feature because they both reduce the realism of a render because they destroy shadows rather than correcting them. To turn off the Skydome feature just make sure the color swatch in the Skylab is fully black.

    If you want realism (which you never said you were after, I know) here are a few considerations about lighting.

    1. 2/3 of the Sunlight that strikes the Earth is scattered by the atmosphere, only 1/3 arrives as direct illumination and direct shadows. That means that if you are lighting a surface and most all of the illumination is coming from the sun alone then you have technically overblown your sunlight. Instead you should lower your sunlight and increase your indirect light.

    2. Considering what I just stated above, it would stand to reason that the Sky and the sky color are the primary light influences for an outdoor scene with direct sunlight giving the emphasis. Direct sunlight should be the highlight, it should be the frosting, it should not be the entire cake.

    3. Bryce 7 gives some really great tools for creating realistic indirect sky light. It is important to realize that indirect light casts soft but important shadows. Shadows are what give a model contour and form so preserving model detail while lightening the shadows is a paramount concern. IBL is a great way to do this. You can convert the current Bryce sky into an HDRI (dont worry about the names for now, just focus on what they mean to the render, as explaining IBL in one shot is not wise just yet). Anyhow, once you get the sky converted Bryce will then create a network of virtual radials arranged in a globe around your entire scene. These virtual radials will cast light into the scene from many angles revealing all of the model contours which is the way indirect light should always work.

    4. Bryce 7 also offers Dome Lights and 3D Fill Lights, which also can form a network of virtual radials around your scene providing indirect light from all sides in a natural looking way.

    5. But the most realistic is proper use of True Ambience. I say proper use because improper use will not look good at all. True Ambience is totally different than Material Ambience, so as not to confuse them. Material Ambience renders very fast and operates by assuming a uniform color as the environmental influence that lightened shaded areas of an image. Material Ambience is a very simplified manner of accomplishing the task. But it also doesnt ever look realistic. True Ambience by comparison, actually is a form of GI and is related to the study of black body radiation. The point being, True Ambience calculates the real world values of bounced light from surface to surface, and is by far the most realistic in terms of results. But the render time is also 10x or more. So it all depends on you.

    Another way is to add a Fill light coming from the opposite direction to the sun or just behind the camera at about 5% to lighten shadows or use True Ambience.

    This can indeed by a quick fix of sorts. A lot of it depends on how you plan to use the camera. If like many people, you set your camera position first and then build your scene around your one fixed camera position, then it is possible to cheat the multi-angular indirect skylight into a single point light positioned opposite the sunlight or camera. But this will leave some areas of the model receiving no indirect light at all. so if you move the camera too much this lack of light might become obvious. I still consider secondary light sources to be a better option than Material Ambience or the dreaded Skydome feature because at least standard radials cast shadows which help express model contours, and as mentioned above the shadows are the key to the realism, not the other way around. Light is hardly where the secret lies, shadows are the real deal.

    I used to go about doing as Szark describes, but I dont like being bound to a narrow range of camera angles. So my solution to lighting is much more global, much more about covering all my bases, even the ones that aren't visible in this current shot. For this reason I use only IBL, Domes, 3D Fills and True Ambience. IBL, Domes, and TA take much more time to render than Material Ambience and Skydome, so speed is an important consideration. If you don't have the computing power for the better forms of light, use the cheap ones, just use them well.

    I probably did not answer your question, but hopefully I have led you toward asking better questions. You are doing a super fantastic job of this project you've taken on and I want the final look of the light to be on par with the rest of your work.

    Best of luck.

  • HoroHoro Posts: 4,274
    edited December 1969

    A relatively cheap way that gives sometimes acceptable results depending on the scene is positioning a radial light without falloff and without shadow casting at the camera position. It is a bit like using a flash light when photographing a scene. I use mainly IBL to get a distributed lighting. But it tends to create banded shadows. If the skydome is used to generate an HDRI, switching Sun Visible to off is the best choice most of the time. In this way, a nice ambient light can be accomplished that matches also the sky colour. Lighting, in general, is the most important part because there is no visual art without light.

  • tdrdtdrd Posts: 0
    edited December 1969

    Wow! Thanks for that extensive reply above - it certainly explains a lot.

    Actually I am having a problem with some of my components.
    I realise that when things are in the dark, or shadows, they are glowing.

    For example the window ledge and lintols and soors simply glow white when they should be in the dark.

    So one component is the windows themselves. I wanted white painted woodwork, so I added ambience to make them whiter. However this had has the effect of making them glow as outlined above. I have taken out the ambience now but the window frames are a dull white.
    I have set the diffusion to white - what else can I do to lighten the paintwork?

    Thanks in advance.
    Terry

  • Peter FulfordPeter Fulford Posts: 265
    edited December 1969


    1. 2/3 of the Sunlight that strikes the Earth is scattered by the atmosphere, only 1/3 arrives as direct illumination and direct shadows. That means that if you are lighting a surface and most all of the illumination is coming from the sun alone then you have technically overblown your sunlight. Instead you should lower your sunlight and increase your indirect light.

    2. Considering what I just stated above, it would stand to reason that the Sky and the sky color are the primary light influences for an outdoor scene with direct sunlight giving the emphasis.


    Sorry Rashad, this is fundamentally wrong, both technically and conceptually.

    Taken as wide band energy, sunlight is only approx 30 percent weaker at the bottom of the atmosphere than at the top, as a result of all interactions excluding cloud cover. If we isolate the visible spectrum, the light is even less weakened. Scattering is only one of the interactions, so your 2/3rds reduction figure is impossible.

    This is borne out by direct subjective experience (sunlit surface much brighter than shaded surface) and practical measurement with light meters. If an incident light meter is suspended three feet above the ground under a summer midday sun, it'll measure about 120,000 lux. If a second incident light meter is placed on the ground in the shadow of the first, thus illuminated only by the entire clear blue sky dome, it'll measure about 20,000 lux.

    So on a clear, bright day (I remember those) direct sunlight is approx five times brighter than the sky dome light. Direct sunlight is vastly more significant to a (clear day) outdoor scene than the sky. A photographic analogy would be the sun being the key light and the sky being an all-round fill light. The sun is the gooey, creamy, sumptuous big slice of glorious cake that you stick your whole face in and go gaaaarrgggghhhmmmmpphhhh, and the sky is the marzipan you leave on the side of the plate.

    Of course it's possible to have local effects of haze, etc, in which the proportion of direct sun and sky dome illumination are more equal, but - so long as the sun is shining directly at any level - it will always be brighter than the sky. If you can see a shadow from the sun then the sun is - by definition - brighter than the rest of the illumination.


    In terms of lighting a 3D scene, it should be remembered that the human eye-brain combo has evolved to have a large latitude when it comes to accommodating different light levels (much better dynamic range handling than digital imaging sensors and photographic emulsions). So a realistic looking scene is unlikely to result from a sun brightness setting five times greater than the ambient light chosen.

  • Rashad CarterRashad Carter Posts: 1,034
    edited December 1969

    _ PJF _ said:

    1. 2/3 of the Sunlight that strikes the Earth is scattered by the atmosphere, only 1/3 arrives as direct illumination and direct shadows. That means that if you are lighting a surface and most all of the illumination is coming from the sun alone then you have technically overblown your sunlight. Instead you should lower your sunlight and increase your indirect light.

    2. Considering what I just stated above, it would stand to reason that the Sky and the sky color are the primary light influences for an outdoor scene with direct sunlight giving the emphasis.


    Sorry Rashad, this is fundamentally wrong, both technically and conceptually.

    Taken as wide band energy, sunlight is only approx 30 percent weaker at the bottom of the atmosphere than at the top, as a result of all interactions excluding cloud cover. If we isolate the visible spectrum, the light is even less weakened. Scattering is only one of the interactions, so your 2/3rds reduction figure is impossible.

    This is borne out by direct subjective experience (sunlit surface much brighter than shaded surface) and practical measurement with light meters. If an incident light meter is suspended three feet above the ground under a summer midday sun, it'll measure about 120,000 lux. If a second incident light meter is placed on the ground in the shadow of the first, thus illuminated only by the entire clear blue sky dome, it'll measure about 20,000 lux.

    So on a clear, bright day (I remember those) direct sunlight is approx five times brighter than the sky dome light. Direct sunlight is vastly more significant to a (clear day) outdoor scene than the sky. A photographic analogy would be the sun being the key light and the sky being an all-round fill light. The sun is the gooey, creamy, sumptuous big slice of glorious cake that you stick your whole face in and go gaaaarrgggghhhmmmmpphhhh, and the sky is the marzipan you leave on the side of the plate.

    Of course it's possible to have local effects of haze, etc, in which the proportion of direct sun and sky dome illumination are more equal, but - so long as the sun is shining directly at any level - it will always be brighter than the sky. If you can see a shadow from the sun then the sun is - by definition - brighter than the rest of the illumination.


    In terms of lighting a 3D scene, it should be remembered that the human eye-brain combo has evolved to have a large latitude when it comes to accommodating different light levels (much better dynamic range handling than digital imaging sensors and photographic emulsions). So a realistic looking scene is unlikely to result from a sun brightness setting five times greater than the ambient light chosen.

    PJF,

    It may well be wrong, but there are some reasons to give it come consideration anyway. The proportion described by the 2/3 skylight 1/3 direct light is not an arbitrary assumption on my part. I got the formulation from this and other articles that detail and graph how this proportion works. I assume this statistic is based on the total potential of light, not necessarily applicable to every situation. I can find other articles as well but there is a quick wikipedia reference

    http://en.wikipedia.org/wiki/Diffuse_sky_radiation

    "Diffuse sky radiation

    Diffuse sky radiation is solar radiation reaching the Earth's surface after having been scattered from the direct solar beam by molecules or suspensoids in the atmosphere. It is also called skylight, diffuse skylight, or sky radiation and is the reason for changes in the colour of the sky. Of the total light removed from the direct solar beam by scattering in the atmosphere (approximately 25% of the incident radiation when the sun is high in the sky, depending on the amount of dust and haze in the atmosphere), about two-thirds ultimately reaches the earth as diffuse sky radiation."

    The important processes in the atmosphere (Rayleigh scattering and Mie scattering) are elastic processes, by which light can be deviated from its path without being absorbed and with no change in wavelength.


    The original article details it a bit more and explains the exceptions many of those you mentioned in your post. The 2/3 to 1/3 ratio has provided me some very stable outdoor lighting rigs lately so I am beginning to support it as a general starting point. The more objects that are around to obstruct the sky the more it can throw off this proportion. We also have to consider as you mentioned the other surfaces which can bounce direct sunlight.

  • Peter FulfordPeter Fulford Posts: 265
    edited December 1969

    (quoting wiki page)
    "Of the total light removed from the direct solar beam by scattering in the atmosphere (approximately 25% of the incident radiation when the sun is high in the sky, depending on the amount of dust and haze in the atmosphere), about two-thirds ultimately reaches the earth as diffuse sky radiation."


    Read that more carefully, Rashad.

    It says 25% of the direct sunlight (when the sun is high in the sky) is removed by scattering.
    Of that 25% scattered light, two-thirds reaches the earth.


    Two-thirds of a quarter isn't a million miles away from a fifth...

  • Rashad CarterRashad Carter Posts: 1,034
    edited December 1969

    _ PJF _ said:
    (quoting wiki page)
    "Of the total light removed from the direct solar beam by scattering in the atmosphere (approximately 25% of the incident radiation when the sun is high in the sky, depending on the amount of dust and haze in the atmosphere), about two-thirds ultimately reaches the earth as diffuse sky radiation."


    Read that more carefully, Rashad.

    It says 25% of the direct sunlight (when the sun is high in the sky) is removed by scattering.
    Of that 25% scattered light, two-thirds reaches the earth.


    Two-thirds of a quarter isn't a million miles away from a fifth...


    Ah, true indeed. In fact the actual total of such an arrangement is actually around 1/6, you are most certainly in the ballpark. I do not intend to disagree with that part of it.

    For the sake of simplicity I had not gone too far into the other issue of describing albedo and how that should be factored into the intensity total chosen for the IBL. I was explaining to the OP that IBL would be a good way to go about the indirect light. Typically, users when thinking of IBL are concerned only with the light radiating down from the sky but that is only half the picture and only half of what IBL can do. Considering the Earth's Albedo is around. 34% meaning that there is a lot of indirect light being bounced back upward toward space that the IBL needs to also account for.

    To get the total value of indirect light for a scene, the light being bounced back upward by the local environment to my mind should be added to the influence of the diffuse sky radiation which we will estimate to be about 20% which reveals a rather different total ratio for indirect lighting, though still not 2/3, it moves closer to 50/50. My goal was to encourage the OP to using the IBL for more than just the skylight, but also for ground light as well which is what I was implying but not stating properly. Naturally the albedo varies based on the brightness or darkness of the ground level components, so the 2/3 ratio I am giving is assuming we er on the side of little too much light rather than too little. In most scenes there are terrain mountains building and other items that are going to block much of the distant traveling light from an IBL probe. Using the 2/3 ratio ensures that even with fully mature shadows and lots of obstructions there should be enough light to make everything look natural even in a dense landscape or cityscape.

  • Rashad CarterRashad Carter Posts: 1,034
    edited December 1969

    I should probably explain a little further what I intend. In that long post I started using the terms indirect light and skylight a little too synonymously. In my own scenes I have developed what I call the EarthGlow Dome Light Strategy. It breaks up the elements of the outdoor light into three stages, Direct sunlight, diffuse skylight and diffuse ground level EarthGlow. The current proportions for a surface illumination are 2/3 indirect light split between the skylight dome and the Earthglow Dome with the Earthglow Dome a little brighter overall than the Skylight dome. The reason is as you observed, the sky itself can only do but so much but once skylight bounces off surfaces it in a sense gets brighter, amplified. Or another way to think of it, not all skylight is absorbed the first time it strikes the Earth so how do we account for the skylight that continues to bounce around from surface to surface? Clearly sunlight is intense and bouncing from surface to surface as well.

    Complicated multiple dome strategies are probably out of his league for now. But in time. For now he will probably have to try to do everything in one shot with the IBL.

    When we consider a scene like the one he is constructing with lots of sky, but also lots of obstruction by buildings and trees, he will need more light than expected.

    Using one of my own works as an example, I have uploaded two versions of a scene I've been working on for a bit.

    The original version played it safe with all of the indirect light intensities right around the 1/6 range you described. Since the sky is dark blue, I assumed it would scatter only a small amount of light. The ground level light was also conservatively set. The light in this scene was intended to be that of a vivid mid-day tropical type of environment based on the basic rules. Over the next few weeks I noticed that sometimes when I re-viewed the image it no longer looked as my mind remembered it, it looked a bit like evening, like the sun was setting even though it was high in the sky, the shaded areas were just too dark. Why doesn't it look like vivid daytime every time I look at it? What missing? God knows the sunlight is plenty bright. What must I do next?

    I played around with the balance of total indirect light to total direct sunlight and discovered that to produce the vivid daylight I was after I'd need a lot more indirect light than I'd ever imagined, far beyond the 1/6 proportion because I needed to account for stray rays of light flying around all over the place.

    So here is a comparison. The original render used Bryce trees, the new one uses Carrara trees and I've even begun a new generation of trees because I dont like the way these turned out.

    Anyway, to my mind the second version does a much better job of creating that sense of vivid daylight than the original render.

    As always I am open to your feedback and respect your ideals so please provide any insights you can.

    I have also included a few example shots from the internet I'd like to use as references for the type of light distribution I was after.

    Clearly the type of camera used for these shots has a huge impact on the way they look, so in that you can also give me advice. Thanks Bud.

    philippines-island-08.jpg
    500 x 333 - 155K
    tahiti-moorea-polynesia.jpg
    728 x 547 - 104K
    Tropical_Retreat.jpg
    960 x 720 - 187K
    AA_10.jpg
    1260 x 840 - 2M
    Meet_Me_on_the_Beach.jpg
    1180 x 840 - 1M
  • LordHardDrivenLordHardDriven Posts: 917
    edited December 1969

    Well one thing I know for sure after reading the debate you two have going is...I want some cake! :)

  • Dave SavageDave Savage Posts: 1,942
    edited September 2012

    I live in the North of England, what is this direct and ambient sunlight of which you speak? :-S

    Post edited by Dave Savage on
  • HoroHoro Posts: 4,274
    edited December 1969

    I live in the North of England, what is this direct and ambient sunlight of which you speak? :-S

    The opposite of rain :)

  • ChoholeChohole Posts: 19,417
    edited December 1969

    I live in the North of England, what is this direct and ambient sunlight of which you speak? :-S


    It's that strange light which sometimes peeks out from underneath all them black and grey clouds,

  • GussNemoGussNemo Posts: 1,855
    edited December 1969

    I live in the North of England, what is this direct and ambient sunlight of which you speak? :-S

    Something produced by an extremely bright, powerful, orb, outside the earth's atmosphere. BTW...what is this "rain" you're mentioning? Something new?

  • Dave SavageDave Savage Posts: 1,942
    edited December 1969

    chohole said:
    I live in the North of England, what is this direct and ambient sunlight of which you speak? :-S


    It's that strange light which sometimes peeks out from underneath all them black and grey clouds,

    Maybe in Wales it does... The only light that shines in the sky here is occasionally when the Police Helicopter is searching for a criminal of some kind. :lol:

  • GussNemoGussNemo Posts: 1,855
    edited December 1969

    chohole said:
    I live in the North of England, what is this direct and ambient sunlight of which you speak? :-S


    It's that strange light which sometimes peeks out from underneath all them black and grey clouds,

    Maybe in Wales it does... The only light that shines in the sky here is occasionally when the Police Helicopter is searching for a criminal of some kind. :lol:

    :lol: Think they could hold still enough to use the light in a render?

  • Peter FulfordPeter Fulford Posts: 265
    edited December 1969

    _ PJF _ said:

    Two-thirds of a quarter isn't a million miles away from a fifth...

    Ah, true indeed. In fact the actual total of such an arrangement is actually around 1/6, you are most certainly in the ballpark. I do not intend to disagree with that part of it.


    Well, the 1/6th is "in the ball park" and the 1/5th is the final score. The "two-thirds of a quarter" derived from that information you linked to doesn't take into account that scattering is only one of the processes that diminish direct sunlight (a fact I mentioned earlier). The other processes lessen the direct light further without adding it to the skylight, and the proportion of direct light thus decreases. The result is a clear summer noon figure of 20% skylight.

    By saying "two-thirds of a quarter isn't a million miles away from a fifth", I was merely pointing out charitably that the logic of the statement you had previously misread led to a similar result as objective measurement.


    It is difficult for me to compare your images with regards to realistic lighting. The first is such a more realistic looking image in overall aspects that any benefits of lighting in the second are obscured (to me). I think if you transferred the foliage materials from the second into the first, you would be much happier with it. God may know the sun is bright enough in the first, but I'm a doubting Thomas. I think if you increased the brightness of both the sun and the fill lighting, you would be closer to a Maldives look. Reduce the specularity of the water, and make the reflection blurry. Reduce the size of the girl's thighs. ;-)

    On the whole I don't like IBL and image domes. The result reminds me early of TV westerns (Lone Ranger, etc) where they mixed location and studio footage. The studio footage stood out unrealistically like a pretend sore thumb, and broke the spell. IBL does that to me. Everything looks lit with lots of studio lights in a hurry.


    BTW, Rashad. When you want to invite discussion of technical aspects it's probably best to use simple, example scenes. It's pretty difficult to dive in and academically critique creativity that has obviously had many, many, many hours of dedicated effort and police work - sorry - passion poured into it.

  • LordHardDrivenLordHardDriven Posts: 917
    edited December 1969

    You know, not to ruffle any feathers but as a person not involved watching this debate develope I find it kind of hard to consider the discussion technical or an academic critique of creativity when one says things like "two-thirds of a quarter isn’t a million miles away from a fifth" such a statement feels like something more suited to sarcasm then academia. I mean how is it academic to use vast distances of millions of miles to say that two fractions aren't that different from one another?

  • HoroHoro Posts: 4,274
    edited December 1969

    You know, not to ruffle any feathers but as a person not involved watching this debate develope I find it kind of hard to consider the discussion technical or an academic critique of creativity when one says things like "two-thirds of a quarter isn’t a million miles away from a fifth" such a statement feels like something more suited to sarcasm then academia. I mean how is it academic to use vast distances of millions of miles to say that two fractions aren't that different from one another?

    I find Peter's argumentation entertaining. It's an exercise for for the brain.

  • Peter FulfordPeter Fulford Posts: 265
    edited December 1969

    ...such a statement feels like something more suited to sarcasm then academia...

    I only inserted "academically" after I noticed I'd written "many, many, many" (dropped another '80s bad comedy clue in there, too). I've made some effort to break up the formal discussion with silly asides to keep things friendly, but if you prefer to feel some sarcasm - go right ahead.

    I mean how is it academic to use vast distances of millions of miles to say that two fractions aren’t that different from one another?

    It isn't. The metaphorical statement "isn't a million miles from" specifically implies a lack of vast distances of millions of miles.


    It's important to stay calm and work to break down the barriers to communication.
    http://www.youtube.com/watch?v=PEK5P2G5h1k

  • Rashad CarterRashad Carter Posts: 1,034
    edited December 1969

    Mark,

    Peter just likes to throw a little silly in with his serious. We haven't always gotten along well but now we get on fine. I dont want to mislead the OP so I appreciate his feedback, even if he can be a little passive aggressive here and there, He's my Bud.

    Peter,
    As you know, I am a paranoid obsessed type of person, never ever ever happy with ANYTHING I've made. I am curious to know which aspects of the first version you find more realistic than the second. The first version won a lot of feedback about the water not looking right, that the foam was missing. The whitening of the water toward the shore was my attempt at foam, it didnt go over well with viewers. I decided for the new one to use a real terrain for the water and to scrap the slab. The foam I also took in a whole different direction. I even applied a caustic gel to the water in the second one for a little more realism, but alas I have no idea if any of it worked. I do appreciate any feedback. Thanks again Peter.

  • pumecopumeco Posts: 0
    edited September 2012

    As you know, I am a paranoid obsessed type of person, never ever ever happy with ANYTHING I've made.

    But to your credit, at least you still show it even if you're not happy with it, and that's something I personally never bring myself to do which is why you never see renders from me.

    Anyway, what I wanted to say was something about the water, why it looks wrong:

    Out of the five you posted, the first two are laughable when I consider your skills with Bryce. You're not an amateur but my dog can render better water than that. The last three, however, the water looks very good, but on the very last one, there is a perfectly clear indication of what's wrong with the water.

    Refraction looks wrong.

    Over recent months I've seen hundreds, no, thousands of beach and coastline photos of Ibiza (Spanish island), and one thing that strikes me odd about your last render is the refraction, it's picking-up far too much detail and that makes the water look odd. Number three and four don't appear to suffer from it as much, but the fifth makes it obvious that refraction is at least one of the issues.

    Comparing to render number five:

    Look at how detail is refracted in this angle:
    http://www.flickr.com/photos/victoriapeckham/6116273670/

    Compared to this angle:
    http://www.flickr.com/photos/globalestates/1589328828/

    You'll notice it hardly looks any different, so what you need to be asking yourself is, why?

    Lots of things to consider, but mainly, bear in mind the complexity of the ripples or waves because although that doesn't change the refractive index of the water in real life, when we render water we need to make-up for deficiencies we have elsewhere (and unless we're totally obsessed, we all render them). For example, we know if a face is fake because we pick-up on things, and it's the same with water, because although it is visually endless, we still know when something doesn't look right, and when a render of water doesn't look right, it is because we failed in other areas.

    The only way you will get accurate water is to know more about the water and model it, surface it, and render it as accurately as possible (remember, it's a ray-tracer, has no mind of it's own, and does exactly what you tell it to do. But we don't have to be super accurate, so we need to make up for that deficiency. So, while you might have a refractive index that works at a certain angle, it is just a fluke because other setting that are wrong are allowing it to pass as acceptable, but that might not be the case when you move the camera to a different angle.

    Shapes of the ripples themselves is going to be pretty much essential to make it believable, and this is why people find it easy to render calm water but fall flat on their faces when they attempt an ocean. Calm water can be anything from a glass like finish (easy) to a slight soft-edged ripple (still easy). Oceans are a totally different thing, and if you give your water the properties used for an ocean when you're rendering calm water, we know it's not right the moment we see it.

    Not very technical I know, but it's the same no matter what we render (I've pointed this out many times). Whenever can't do that, forget about following simple things like, ah, I set my refraction to water so that must be correct. Nope, so as well as the refraction you need to consider the shapes of the ripples and waves as well.

    Another aspect of making such a render believable is demonstrated here:
    http://www.flickr.com/photos/andybateman/2402808893/

    Post edited by pumeco on
  • Peter FulfordPeter Fulford Posts: 265
    edited September 2012

    pumeco said:
    The last three, however, the water looks very good, but on the very last one, there is a perfectly clear indication of what's wrong with the water.

    Refraction looks wrong.


    Well I was having a cup of tea at work - but now I'll have to wipe it off the screen and go and make another.

    Yeah, c'mon Rashad - you can do better than that! :mrgreen:

    Post edited by Peter Fulford on
  • pumecopumeco Posts: 0
    edited December 1969

    I don't know what's funnier:

    A - You being a posh git and still having to make your own tea, or ...
    B - You haven't noticed the refraction is indeed wrong :mrgreen:

    And anyway, I was being perfectly serious.

    Refraction (and Reflection (and Specular)) are vital, especially with stuff like water which depends on all three. People screw-up on water a lot, just like they screw-up on eyes a lot. I mean how many times do you see a render where the eyes look dead or glazed-over?

    I see it a lot, too often, and It's the same sort of problem that arises when dealing with water. To deal with it, things need isolating and to be tweaked in a more controlled scene environment if accuracy is needed, otherwise, it's just observational, knowing when it looks wrong and tweaking it in it's surroundings at a predetermined camera angle until it doesn't.

    PS: The only reason you have to wipe the Earl Grey off' your monitor is because you saw that arse. At first, there was merely the sound of the bottom of your cup rattling against the saucer as you trembled, but then suddenly you could contain yourself no more and, well, found yourself needing a cloth for the monitor :-D

  • LordHardDrivenLordHardDriven Posts: 917
    edited December 1969

    _ PJF _ said:
    ...such a statement feels like something more suited to sarcasm then academia...

    I only inserted "academically" after I noticed I'd written "many, many, many" (dropped another '80s bad comedy clue in there, too). I've made some effort to break up the formal discussion with silly asides to keep things friendly, but if you prefer to feel some sarcasm - go right ahead.

    I mean how is it academic to use vast distances of millions of miles to say that two fractions aren’t that different from one another?

    It isn't. The metaphorical statement "isn't a million miles from" specifically implies a lack of vast distances of millions of miles.


    It's important to stay calm and work to break down the barriers to communication.
    http://www.youtube.com/watch?v=PEK5P2G5h1k

    Umm perhaps you didn't realize this but typically when people feel the need to break up a formal discussion with silly asides to keep things friendly, those asides are quite often considered sarcasm. Being that you like to go academic with discussions then surely you know sarcasm can be a form of humor. The thing is typically when one feels the need to break up a formal discussion with humor they don't refer to that discussion as an academic critique.

    Yes I understand the function of the word isn't in your original statement but saying a thing isn't something it obviously isn't is awkward and clumsy, not academic or sarcastic even.

    I'll pass on the video, I'm perfectly calm and the barriers to communication appear to me to be a figment of your, perhaps, overactive imagination.

  • LordHardDrivenLordHardDriven Posts: 917
    edited December 1969

    Mark,

    Peter just likes to throw a little silly in with his serious. We haven't always gotten along well but now we get on fine. I dont want to mislead the OP so I appreciate his feedback, even if he can be a little passive aggressive here and there, He's my Bud.

    That's all fine and dandy but I wasn't coming to your defense, you're a grown man, I presume you can defend yourself. I was mainly seeing if your bud there could take as good as he can give, preliminary results suggests the answer is no. I was also trying to subtly suggest that such "academic critques" don't really belong in a forum whose primary function is to help Bryce users solve problems they're having. I really doubt the OP understands how to get reasonable light any better after having read you two debating your personal opinions of what sunlight is.

  • Peter FulfordPeter Fulford Posts: 265
    edited December 1969

    pumeco said:
    I don't know what's funnier:

    A - You being a posh git and still having to make your own tea, or ...
    B - You haven't noticed the refraction is indeed wrong :mrgreen:


    Try C - You haven't noticed...


    And anyway, I was being perfectly serious.

    :nodding:


    It's a bugger about the tea making. Austerity, and all that. We have an old saying here at PJF MegaCorp: it's a recession when your neighbour loses his job; it's a depression when I have to make my own tea.


    I mean how many times do you see a render where the eyes look dead or glazed-over?

    Oh, I know. There's an example used on this page but in this case the render is spot-on accurate.

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