New to blender. Question about YafRay.

[iluvgfx]

Hi.

Is it this page?

http://wiki.yafray.org/bin/view.pl/UserDoc/WebHome?CGISESSID=383e3cb7efced0919e46158731bc3d32

Even i started fiddling with Yafray since yesterday. Lets see how it goes.

Greetings,
Satish.

[Brick-top]

Yes, that's the one. thanks! but what do you get when you have "tune photons" selected? Do you get the photon map?

I've also noticed some "inconsistencies" in the behavior of the raytraced shadows and I don't know the cause, sometimes no matter how I change the radius of the light I allways get the same result, which is an extremely soft shadow. normally If I close blender and reopen the scene the shadows start behaving "normally" again.

But I would really like to sort out the photon map question.

thanks!

[Brick-top]

I just discovered that as I select Photons in the Yafray tab I get the extremelly soft shadows I talked about in my previous post and as soon as I deselect Photons my previous settings for raytraced shadows work again.

[Brick-top]

apparently it was just a matter of settings, I increased the GI power to 50 and now I can see the photons with the Tune photons option enabled. But it's been tough to get the results I want

[OpenDut]

Haha.

No need to crank the GI power to 50.

With Yafray, you need lamps (spot/point) to see the GI stuff. I believe Area lamps don't generate photons.

If you're doing an indoor lighting where the walls of the room is covering up the sky and ground, then you'll need lamps for sure, otherwise you'll just see pitch black.

When yafray is on, the lamps generate the photons. You don't use a photon lamp to generate photon, you just use normal maps.

Thus you need actual lamps to generate the photon map when you press Tune Photon. You can't rely on your white background sky.

So try putting some lamps into your indoor scene, that should fix the problem.

I don't use tune photons but you can experiment with it, if you want.

Here are some example:

(No lamps)

http://img.photobucket.com/albums/v639/Ryu_Kaiser/gi_1.jpg

(1 Point light included)

http://img.photobucket.com/albums/v639/Ryu_Kaiser/gi_2.jpg

[Brick-top]

Where did I say I was relying on a white background sky? I was doing my experiences with the default lamp, I don't know if I'm doing something wrong or expecting things I shouldn't expect, but I only see the photons and thus their effect when I crank up the GI power to 50, and I raise the "Exposure Adjustment" to 4~.

[Brick-top]

Could you explain the meaning of "the lamps generate the photons. You don't use a photon lamp to generate photon, you just use normal maps."? I may be missing some knowledge to understand this.

[OpenDut]

There are Photon lamps in Yafray, I'm saying Photon lamps don't light up your scene. They're only there for caustic effects.

http://img.photobucket.com/albums/v639/Ryu_Kaiser/Photon_lamp.png

I didn't say "Brick-top is relying on white background sky". I'm just saying "don't rely on white background sky", an advice for those who is or are reading.



You should not need to increase your GI power to 50. My GI power is usually on 1 (99%) of the time. I manage to light my scene with Yafray.

Things to check to make your Yafray light:

- You have lamps in your scene (not photon lamps)
- Dist value is enough to reach your objects, otherwise you'll see nothing.
- Your lamp is not blocked or covered by an object (obviously if you block the light source, you get no light)


I don't tend to use the Tune Photons, that only shows you how smooth your photon map is, which in effect tells you in advance the quality of the lighting distribution in your room. The default settings for the Yafray panel should already give decent results.

Good luck.

[Brick-top]

I'm sorry, I thought your post was directed only to me, apparently it was more of a tutorial. I haven't had noticed the photon lamps, fortunately I wouldn't get caught in the mistake of using them to light my scenes because I always check the little notes that appear whenever you leave the mouse cursor over a button, but I understand it might be easy to use the photon lamps for that purpose if you don't read the notes.

Thanks a lot for your tips on rendering with yafray they have been very helpfull in my experiences, for example I have learned that light postion affects lighting a lot more than I for some reason was expecting. I guess I got caught in the mistake of expecting a similar behaviour with similar settings as I use when I have something to render in the software I mainly use, Maya/Mental ray.

Thanks a lot, sorry if my english sounds weird.

[CGTalk Moderation]

This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.