Dome Reflections problem

[sunny]

Hi all,

Please excuse my ignorance, as I'm a newbie with VRay. Here's my question. How can you create a reflection object which does reflections only? My reflection object is affecting the lighting as well. I've saved some screen shots but I haven't a clue as to how to attach them to this forum. I'll try to explain.

I've created a semisphere. Reversed the normals. Mapped a reflection image and positioned it around my building. I do not want to use the Environment Reflection/Refraction because I can not accurately position my reflected image plus the perspective is incorrect. I set the semi-sphere not to cast shadows and set it to be invisible. When I render the scene, there is a distinctive "shadow" left where the sphere would be if it casts shadows. But I've set it not to. The actual reflection itself is what I wanted.

If someone would be so kind as to explain how to post an image up to a simpleton like myself, I'm sure this would all become clear.

Thanks for any advise you can offer.

SunnyC


[/img]

[Palee]

Hi,

First of all, you have to upload your image's somewhere to the web.
and when you compose your message, below the subject line, you can find a little tag called 'Img'.
Click on that, copy/paste your image's URL, then click on the 'Img' again.
That's all!

Best regards,

Palee

p.s.: btw, when you hold your mouse upon a tag, you got the hints, how you can use that...

[Fermi]

Hi Sunny,

So you are Vraying... ...good.

You have to exclude that object form the GI process, unless there is a better procedure this is one way to do it:

You calculate the Irradiance map with the geometry that has your environment hiden (and in general render settings you have "render Hiden" Unchecked).
In advanced irradiance map paramenters you make sure you check Autosave at render end. and choose a file name

When you are done you render youf final image, now with environment geometry unhided and you reuse the previously prerendered imap checking "From File" instead of single frame, and browsing to your imap location.

If you are rendering to high res stills, you can prerender the imap from a low res image (say 640x480) , using imap settings such as -3 , 0 and reusing it for the high ress image with good results. (do some testing)

Another alternative is to use the bitmap directly in the normal MAX/VIZ environment, then in Vray environment check override MAX thus the map won't effect GI at all without the need to prerender.

hope it helps.

Fermí

[Rick Eloy]

What's that again?

You calculate the Irradiance map with the geometry that has your environment hiden (and in general render settings you have "render Hiden" Unchecked).
When you are done you render youf final image, now with environment geometry unhided and you reuse the previously prerendered imap checking "From File" instead of single frame, and browsing to your imap location.

Ok, Fermí. This is nice, but now I have one question myself. Everytime I tried to use this procedure, the final result was that the previously hidden geometry showed up with lots of artifacts. Only them, not the rest of the scene (not excluded from the GI calcs). Why's that?
To avoid that, I'm often forced to render everything (no hidden geometry) in order to save the solution and only then have it rendered the size I want. Is there a reason for that?

[]
Rick

[GoncaloP]

why do you need a dome? Just wondering...

Gonçalo

[egz]

And why is this in image uploads?

[Fermi]

Hi Rick,

Don't know why you get this problem...

in the case of Domes for backgrounds it works, but the most likely will be excluded form lights and will be self illuminated... ( oi gonçalo? , they work, even if you don't need them :P )

And lot of people is using this exclude from imap calculation hiding, and render with reusing precalculated imap for transparent materials, Glass for instance with succes.

If you happen to use VIZ4 Camera correction modifyer, uncheck "Shade Context compatibility" in System settins. (Gonçalo's tip)

Fermí

[Fermi]

And why is this in image uploads?

Because original Sunnys question was double, about domes with GI and about how to upload images to the forum, most likely he pretended to illustrate his question...

And I wonder how bad is it being here?

Fermí

[egz]

Forum description: Show off your art work rendered with VRay

So it is for showing off finished or WIP art, not technical questions. The post should be in General or Bug reports. I don't mean to be a stick in the mud, but if this was to get out of hand, the entire forum will be a mess.

[sunny]

Ohhh, so harsh!!! No worries Fermi. I've got thick skin.
I wasn't expecting a big welcome from anybody.......
other than yourself at least!!!

Sorry to stir up such a debate for rest of you guys and girls.I didn't know we were all so tense in this forum. I Promise I won't do it again. I'm not a rebel at heart

Thanks for your reply Fermi. I'll definitely give that a go. You're spot on Fermi. I read the Forum descriptions for General and it said not to post any images there. The only place that said to post images was in Images upload. Stupid me, after typing out my message, I realised I didn't have a place to put my image. Hopefully attached to this post are the original WIP images I was going to post with my first image.

Sorry for causing you to pop a vain Egz. Nice to meet you too, by the way.

Since I started this mess, I might as well finish off by explaining why I started this thread.

[img]ftp://ivolveftp:ivolve@203.34.172.178/From-CroneNation/ivolve/vray/wsq-test.jpg[/img]

[img]ftp://ivolveftp:ivolve@203.34.172.178/From-CroneNation/ivolve/vray/reflect-example.jpg[/img]

The first image is the building I'm working on. Positioning the reflection at the right scale has become a pain. I'm used to using Domes. Hence, the tests with the second image. I hope this clears things up a little and doesn't become a waste of everyone's time.

Thanks with your perseverance.

Sunny.

[egz]

Sorry for causing you to pop a vain Egz. Nice to meet you too, by the way.

Hey, didn't mean to sound harsh (I'm not a bad guy) I just felt the post was in the wrong section, since this is usually for critiques of finished or WIP images. Images are posted in all the other sections too, if relevant to problems etc.

Nice to meet you too, and welcome to the forum

[sunny]

No problems Egz. I've seen a lot of your stuff and would
welcome any knowledge you can share. By the way, I like
your VRayinfo site. Very informative.

Thanks Fermi. Your suggestion worked a treat. The simplist answers
always do.

Sunny

[Psy]

all i see are lil red x's

if u'd like, i can host any of ur pics for u (incl. future ones).

mail me if u want.

psysuss@hotmail.com

[sunny]

Hi Psy,

That’s strange, I can see my images attached to the thread. Can anyone
else see the attached images?

Thank you for the offer. I wouldn’t want to impose on you though and end up being a pain in the butt. How embarrasing. I can create images of non existing buildings but I can't post some images.

Part of the problem might be that I'm posting the image on our FTP site which has a username and password. However I include that info into the string command. This is the command I use minus the [img] bits. Can anyone spot the error?

ftp://usernameassword@ip address/From-CroneNation/ivolve/vray/max-screen.jpg

Thanks

Sunny

[Psy]

i have a 5gb bandwidth limit. each month i use 50megs of it.

i doubt u'd be imposing.

p.s. the reason u see it is because it's cached in your browser temp dir.