The atmosphere rendering in TG2 is simply amazing, the clouds that you can make are the best around..but.. there is something up there in the sky that isn't quite up to the standard of the rest of the sky. Yes i'm talking about the sun. Sometimes it looks ok but at lower altitudes especially it can look a bit flat. Sure you can do a bit of post pro and make it glow and dazzle but I think this is one area where TG needs some work. I guess i'm talking about the sun having a corona, something to make it bright and glowing.
Just as a quick test I rendered a sun in TG and one in the free PLE version of vue to compare. Now the atmosphere in vue is not up to TG standards in general, especially the clouds, but I do think that the vue sun looks better, compare how flat the TG sun looks next to the vue sun. I think i've mentioned this before a while ago.
So planetside, any plans to look at the sun for the final version, or maybe for a 2.x update?
lol. yeah it's a good comparison between the two. I've always prefered Terragen over Vue and especially now with transparency. But Vue is aimed at a more generalised advertising and occasional artist demographic. Terragen's higher quality allows it to be used in movies and tv.
The sun newspaper
Vue has been used in quite a few movies, PG. http://www.e-onsoftware.com/showcase/spotlights/?page=0
But, the sun could use something to give us what we're seeing in Vue. Not sure why not, unless there's some computations in the math that we'd be messing with that Matt would rather spend elsewhere.
Yes but only ever for fantastical settings and in the case of a few of those on that page, adding an overlay to a real world image.
Well I only used vue to give a quick idea of what I meant, I could have used a photograph for instance. I think the vue sun could be improved as well but at the moment it's better than the TG disk sun.
Quote from: calico on August 06, 2008, 11:22:40 AM
Vue has been used in quite a few movies, PG. http://www.e-onsoftware.com/showcase/spotlights/?page=0
My own list of TG (O.x and v2) use in film and commercials almost equals that list (and will probably equal it at the end of the year). Vue's list isn't impressive at all, sorry. Especially when you consider the cost and resources, and the renderer being far crappier than TG2.
An hour ago, I was watching the National Geographic channel and 'Megavolcano' was on. I was saying to myself: 'That looks very Vue-ey'
I came online after it was finished and perfunctoraly scanned the threads in here, to unwittingly find the link to the very show I was watching...
http://www.e-onsoftware.com/showcase/spotlights/?page=6
It's the Vue palm trees that give it away, everytime.
Talking of vue I see that version 7 is going to be released in the next few months.
It includes the 3rd generation of their ecosystem and 2nd generation spectral 2 atmosphere engine. I can't wait to see what they have come up with. I wonder if the spectral2 engine can match TG2's?
Hi,
I thought I should mention that at some point, past TG2 final release at this point, when we have the renderer behaving nicely and all that, we will be looking into much better tools for placing vegetation etc. At the moment, as with quite a bit of stuff, the Populator is really just at a basic level of functionality. It allows you to place a lot of objects quickly and easily, with some control over their appearance and location, but it definitely is not the pinnacle of what we envisage for this. We've had ideas about this for a long time, but haven't been able to implement as of yet. This is essentially just to say we realise that the vegetation placement system needs to do more and better, and that the intention is to improve this in the future. Obviously Vue has better tools in this respect for now.
Regards,
Jo
Thats good to hear Jo. Any comments about the sun?
Jo's reply would tell me that the corona is not on top of the list for improvement anytime soon. :'(
there are easy ways to fix that problem with the sun
you can set the haze brigtness to 4,1.5 then dim the sun to arounf .5 that makes the sun look more realistic by the looks of the picture you have shown us you have changed very little of the default settings so thats why the sun looks like it does
Jo thats great to hear about better population systems would it be similar to vues ecosytems? it wouldbe great if you could add a paint tool as well where we could paint the vegetation models on where we want like you can in vue ;D
Lightning, I just used the default scenes in both vue and terragen, I didn't want other settings within the software to affect the suns look. Changing the haze values and/or dimming the sun has an impact for the whole scene, not just the appearance of the sun, therefore its not always an option. Having some kind of corona setting would get the desired effect without affecting the rest of the scene.
As many of you know the reddening of the sun at sunrise and sun set is due to Mie Scattering due to red been longer in wavelength than blue due to the light having a shorter distance to travel due to the low angle of the sum in the sky. For Terragen to be more realistic (If not implemented already) Mie Scattering (In Nature this is multiple scattering in the forward and backward direction [If Memory serves]).
Regards to you.
Cybet-Angel
I believe Mie Scattering has more to do with why the clouds look white and the sky looks blue. And I believe the reddening of the sun when low to the horizon is caused by Rayleigh scattering. Besides coloring isn't what reck is looking for, I guess we need a temperature dial to turn up the heat of the sun (not the light) to give the corona effect. LOL ;)
Actually the sun itself in real life would appear as a virtually perfect disc without the atmosphere, so it is in fact the atmosphere that you want to look to for these effects. Looking at the Vue image I'd actually say that it looks decidedly *unrealistic* compared to the real world, except in very specific circumstances. Normally, if you can see the sun that clearly (i.e. there's not significant glow around it virtually hiding its outline), then it is pretty sharp. The only time you might see something like the Vue image is in fog or a sand storm. But feel free to find photo reference to prove me wrong. ;D
In any case the "Glow in atmosphere" setting accomplishes at least part of what you're looking for, I think - try turning it off and your results get worse. Ok, that's not quite what you want, to make things worse. ;) However, see if turning off Visible Disc is more to your liking...
Even if that does improve things for you, I would agree that the sun rendering is not ideal. Again I would *not* say Vue's is particularly superior (although I grant many people may *think* the sun looks like that), but there are certainly things that could be handled better in TG2 in regards to the sun. A proper "glow" function for bright surfaces would help a lot. The simplicity of the "visible disc" function is probably to blame for a lot of the realism issues in this case.
- Oshyan
I don't know Oshyan, I think the sun at lower altitudes should have more of a glow and brightness about it, or at least the option to do this. Taking a quick look at some pics via google most of the sunset images don't have such a well defined disc shape about them.
On the other hand there were a few images that did look more like the terragen sun such as the last pic, but the vast majority are more like the first ones. Obviously it depends on the atmospheric conditions at the time, maybe more controls could be added to the sun to try and emulate the first set of pics?
I tried turning off the visible disc but in my opinion it doesn't look good. I shall take another look at the "glow in atmosphere" setting but I have a feeling it would affect the whole look of the sky rather than just the sun. Sometimes you get a great scene setup with lighting and colours just as you want, but you want to make the sun have more brightness and glow without affecting the rest of the scene.
To be fair, though, the photos aren't going to be like a realistic view. Film or digital medium skews the light rays of the sun.
Quote from: reck on August 12, 2008, 03:33:07 PM
Taking a quick look at some pics via google most of the sunset images don't have such a well defined disc shape about them.
That's true. But even in real life when you see a sunset with your own eyes it tends to look more like a glowing sphere than a luminous white disc, maybe not all the time but sometimes (most of the time?) it does.
I especially agree with that when it's sitting over the ocean...due to atmospherics. Too true.
The first reference image you provided looks like neither the TG2 image nor the Vue image - I think that's about how it looks if you turn off visible disc, or if you just have a high brightness/glow. The 2nd image looks closer to the TG2 than Vue. I do agree that more control is needed for the sun and the sun disc effect in particular is too simplistic, as I noted before, but I don't think Vue necessarily has the more realistic solution right now, regardless. ;)
- Oshyan
I did some space renders, and in those the sun looks extremely 'disky'. There the glow would not be caused by the atmosphere, but more by how our eyes react to the brightness, and how it shines through the hairs around our eyes.
Anyways, the brightness of the sun has a lot to do with the glow, and you can't always recognize that it's that bright in a render, until you start saving them as exr files and go play with tonemapping software. Then the brightness of the sun starts to affect the surrounding pixels more like you'd expect.
In nature (Not sure about TG2) the sky its self is a source of illumination due to "Diffuse Sky Radiation" more about which can be found on this Wikipedia article http://en.wikipedia.org/wiki/Diffuse_sky_radiation and time permitting in future the lighting model of TG2 should consider this if it dose not already.
Regards to you.
Cyber-Angel
The worst problem of the TG render is the the sun, even though it is just above the horizon, is still a perfect circle. Just have a look at http://www.tripadvisor.it/LocationPhotos-g608952-Peniche_Estremadura.html#17467154 (http://www.tripadvisor.it/LocationPhotos-g608952-Peniche_Estremadura.html#17467154) or http://www.chocolate-fish.net/img_-3777_lang_italian (http://www.chocolate-fish.net/img_-3777_lang_italian).
Another problem of the TG render (obviously related to the above one) is that the color of the sun disk is the same everywhere. The Peniche image shows well that in realistic conditions the lower part (having its light go thru a large air volume) is markedly redder than the upper part. This effect can be masked by postprocessing or appropriate exposure (as demonstrated by the Brighton Pier image, but this is a photographer decision, not the accurate atmospheric behaviour.
Just to give an example of the obscene complexity of the problem, have a look at http://www.pbase.com/warthog2100/image/52579824 (http://www.pbase.com/warthog2100/image/52579824). There you will find an animation made by several photographies, showing the sunset phenomenas, including the very elusive Green Flash (no, rest assured, Vue does not green flashes, nor does any GC program I know of ;D).
There are situations in which the photographies show almost exaclty the Vue render situation: e.g. see http://www.yepayepa.net/kl18th/wp-content/uploads/Sunset%20Boracay.jpg (http://www.yepayepa.net/kl18th/wp-content/uploads/Sunset%20Boracay.jpg) or http://www.travelblog.org/Wallpaper/sunset_wallpaper_brazil.html (http://www.travelblog.org/Wallpaper/sunset_wallpaper_brazil.html) (scroll to the bottom of the page for the actual wallpaper).
The problem in general is that there is an atrocious difference of illumination between the sun disk and the rest of the scene so exposition time and even slight differences of atmosphere transparency, haze, turbolency, water vapor etc. can make great difference in the final image.
At least, TG should handle the different light path air thickness w.r.t. height above the horizon. This should almost automatically provide sun disk squashing and lower limb reddening.
Bye!!!
Quote from: latego on August 14, 2008, 03:08:24 AM
Another problem of the TG render (obviously related to the above one) is that the color of the sun disk is the same everywhere. The Peniche image shows well that in realistic conditions the lower part (having its light go thru a large air volume) is markedly redder than the upper part. This effect can be masked by postprocessing or appropriate exposure (as demonstrated by the Brighton Pier image, but this is a photographer decision, not the accurate atmospheric behaviour.
Just to give an example of the obscene complexity of the problem, have a look at http://www.pbase.com/warthog2100/image/52579824 (http://www.pbase.com/warthog2100/image/52579824). There you will find an animation made by several photographies, showing the sunset phenomenas, including the very elusive Green Flash (no, rest assured, Vue does not green flashes, nor does any GC program I know of ;D).
The problem in general is that there is an atrocious difference of illumination between the sun disk and the rest of the scene so exposition time and even slight differences of atmosphere transparency, haze, turbolency, water vapor etc. can make great difference in the final image.
At least, TG should handle the different light path air thickness w.r.t. height above the horizon. This should almost automatically provide sun disk squashing and lower limb reddening.
Bye!!!
I must disagree on the point of colour! I've attached a few of my renders which do show clear discolouration with the right atmo settings.
Latego that's very interesting. It just goes to show how many different ways the sun can look depending on certain conditions.
After spending some time looking at this I now think that the TG sun is not as bad as I first thought. It is possible in some situations for the sun in real life to look like the TG sun, but only in some situations. I hope in the future to have more parameters to play with for the sun to simulates the other images of sunsets we've seen.
I have to agree with Mohawk, when I was playing around last night with sunsets the disk does change colour towards the bottom of the disk. Most of the sun was white and then the last 10% had a red/orange tinge to it.
I just now read this thread and wanted to add a few things, until I saw Mohawk's post. I agree with him and his renders show what can be achieved in TG2. You can get that gradiated color sun effect, just by playing with the atmosphere. Yes, it can change the scene somewhat, but thats likely what would happen in real life anyway.
One thing I think TG2 should eventually simulate, is the atmospheric refraction that distorts the shape of things near the horizon - ie, how the sun becomes more "oval" at the bottom when its close to the horizon.
Atmospheric Refraction? :P Yah.
Quote from: calico on August 14, 2008, 11:04:19 AM
Atmospheric Refraction? :P Yah.
It was my tone of voice, wasn't it. ::)
Uh huh.