Image consistency; Light, Color, feel.

[TheBadger]

Hello,

I have been working on a very large project. I am making many still images, and soon animations, of the same world/place. One of the biggest issues I am running into is making renders of this project from different spots and perspectives, that look like they were made at the same time by the same artist.

What advice or methods can you share.

Thank you.

[TheBadger]

I have been looking through the art here in the forums. There really is not a lot of renders done in a series. Where as a final, a scene is rendered from multiple views. There are a few, but only a few... That I could find.

It does seam to be an added difficulty to rendering. That is getting the same look across renders.
I really thought it was just a matter of using the same settings (basically) over all the renders. But there must be more to it. Because I am using the same settings and objects, but getting different outcomes. Not terrible, but different enough to make me want better.

[cyphyr]

Hmm, I think you've touched on something here.
To get a consistency of output across multiple renders of the same scene is very hard, it's one of the main reasons it's taken (still taking) so long on my GreenDeep animation. Change the camera vp and the angle of the sun/lighting changes and not always (ie rarely) beneficially. I suspect even if one was filming a scene with real cameras one would get changing output as the vp changes. What are those silvered boards film crew use to redirect natural light?
I don't have a simple solution for you really. Saving your output as EXR will give you much more control over the final look. Also you could investigate using fill light setups in place of or addendum to TG's native GI, this may give you some extra leverage.
Good luck
Richard

[TheBadger]

Thanks Richard. Im not even concerned with realism (animated/cartoon look is just fine), so using more lights may be good. As long as every render part of the project is consistent, than I will be very happy.
I am looking forward to you finishing your project. When you do perhaps you can detail some of what you ran into as it relates to the question above.
Like I said there is not much talk on this. Probably because theres not much work that relates? The longest sequence I have seen is Ulco's "Garden of eternity", and the only renders I have seen with cuts edited together (that I can recall) is your "Arrival" video. If there are more please link.

What are those silvered boards film crew use to redirect natural light?

bounce lights.

But its not just light that I having difficulty with. Post processing the HDRs is quite a task too.

[TheBadger]

Hi,

Was reading another thread and found something that I thought may apply here

From T-U

The sample positions in screen space are random, so everytime you render the same image the sampling pattern isn't exactly the same
If they aren't random then rounding errors in calculations result in tad tad differences between previous sampled values.
So 2 factors affecting the differences why GI almost never gives the same solution between renders. The only way to avoid this is using higher GI settings.

Martin, if you read this post and think that this statement does not apply to the question of this thread please correct me.

Then assuming T-U's statement does apply, one thing that I really should do (if render times do not become prohibitive) is use the highest GI settings that I can get away with. This will add some more consistency to my renders from different shots of the same scene? Whether or not thats the case should I always try to find the highest settings up to the point where render times become intolerable? Is that the trick in general?

So for example. Say I have a space scene and the render time at HD is 3min per frame. And say the amount of time I am willing to allow for each frame is 45min. So in a situation like this I should amp everything up. Regardless if the positive returns diminish, because there will be at least some quality improvements?

[Oshyan]

Short answer: no.

Finding the right balance of quality and render time is a challenge for almost every app. Unbiased renderers somewhat get away from this in that what you're left with is a pretty straightforward "how long can I wait to achieve the quality I want" and it's really very few settings that control it. But in most other renderers, TG included, there are a number of settings that affect render time, some greatly, some not, and - most importantly - some of them are a larger or smaller factor (or literally have no identifiable impact) in different scenes.

Regarding lighting consistency, yes the higher your settings, the more consistent your results between renders from the same perspective and with same lighting settings will be, though there is still randomness involved. However for animation, if you are using GI, you basically always want to be using a GI cache now that this feature is available. This will actually result in essentially identical GI results between successive renders of the same frame(s), as well as consistency in lighting changes between multiple frames.

Going back to still frames, if "consistency" is a concern as you state at the beginning of this thread, then you really need to establish what the factors are that are causing *in*consistency. Simply assuming it's GI because there are random sampling factors involved is not useful - there are random sampling factors involved in almost every aspect of TG rendering, and most other renderers, too!

Actually, I'm still not entirely clear on what problems you were running into that prompted you to post the original message. You've posted 4 times here about it, but never provided example images, and the only other person to reply indicated that this would also likely be a problem in real-world photo/video shoots (which I agree it is), which suggests your issues may well not be TG-related at all. So until we establish what the actual issues are, it's really difficult to give concrete recommendations. All I can really say is that if you find a scene you're working on to be fast rendering *and* the end result is stable in motion (animation), don't fight that, count it as a blessing and enjoy! More often than not you will be working from the other end, trying to figure out what settings you can *reduce* to give reasonable render times while maintaining the quality and consistency you need. Tools like GI caching help a lot with that.

- Oshyan