HDRI map - Lowering horizon?

[benjaminbogaert]

Hi, I was wondering, is it possible to lower the hdri map horizon? I can rotate it and all but not move up or down.

[notamondayfan]

Essentially no you can't rotate a HDR map vertically, as it is an image.

 

You could perhaps edit the map, perhaps cropping, or stretching the map in an editor to alter the sun height.

 

Or you could use an overcast sky HDR map, and use a light source (such as vray sun) for the sun.

 

Dean

[benjaminbogaert]

Seems tedious... So basically find another or crop the image.. shame I can't use the offset. Okay seeing the previous thread(beauty pass), I can remove the bottom reflection in photoshop and replace them with a different image?

 

Thanks anyhow Dean, I thought it was a longshot.

[notamondayfan]

Yea that's the beauty of using passes in post, you can just adjust single layers, in this case, the reflection layer.

 

Not being able to fully control the light has always been one of my gripes with HDR lighting.

 

Dean

[RyderSK]

Is it because you use hemisphetical HDRi (lower black half) ?

 

If so, modify your HDRi in PS, and add landscape ;- ) But never move the horizon ! The horizon..is where it should be, because it's spherical mapping.

 

 

Edited link: Now it's clear what are these ;- ) Left: Original by peter guthrie (2003, dusk), Right: "

Mix" of PG2003 and daylight (:- )..) CG-Source for ultimate nighttime.

 

Actually HDRi are something people should experiment, not just drop in and swap. I use maybe 5-6 HDRi, but I have created almost 10 version from each !

Edited November 19, 2013 by RyderSK

[benjaminbogaert]

Yeah, its the one with black lol. Nah in a way its a good thing, now I can try out some new stuff in post-poy lol. these are really nice btw, where can i buy em?

[RyderSK]

Yeah, its the one with black lol. Nah in a way its a good thing, now I can try out some new stuff in post-poy lol. these are really nice btw, where can i buy em?

 

I've edited my post, check it :- ).

 

Anyway, using hemi-spherical HDRi is pretty bad because it produces artificial lighting, unless you have fully modelled environment. Even bounced light from surface (now below horizon) contributes to scene lighting.

[CliveG]

Anyway, using hemi-spherical HDRi is pretty bad because it produces artificial lighting, unless you have fully modelled environment. Even bounced light from surface (now below horizon) contributes to scene lighting.

 

Does just dropping in a VrayPlane resolve this as it supposedly goes horizon to horizon? Even if you make it invisible to camera, would that still resolve the lighting?

 

Also if so is it correct to just assume that they (VrayPlane & HDRI) align, or can the black of the HDRI actually occur off the zero Z too?

[RyderSK]

Does just dropping in a VrayPlane resolve this as it supposedly goes horizon to horizon? Even if you make it invisible to camera, would that still resolve the lighting?

 

Also if so is it correct to just assume that they (VrayPlane & HDRI) align, or can the black of the HDRI actually occur off the zero Z too?

 

Correctly created hemispherical HDRi will have the black exactly below horizon, after all it is artificialy created, it could be stitched to have anything. I am not sure where the preference for only hemispherical imagery came.

 

Yes, VrayPlane does the same, the difference will be that VrayPlane will bounce of light, so there will be GI happening before entering our scene, with hemispherical HDRi the below horizon will be sampled directly for lighting information (i.e, it will be much faster, and neither affect scene bounding box).

 

With VraySky the plane is a must.

[benjaminbogaert]

As Always Juraj, Thank you for the information! I'l keep this in mind when i'm buying new HDRI's but damn they be expensive!

[RyderSK]

As Always Juraj, Thank you for the information! I'l keep this in mind when i'm buying new HDRI's but damn they be expensive!

 

C'mon, no they aren't :- ) relatively, "true" high-end spherical HDRi like MOOFE cost 150 euros just to "play" with for 3D guys, otherwise it's 800+ for single set ! Compare that with 20 euros and you'll see it's good deal :- ).

 

At one time, last year, I really started crusade to find the best ones out there, and bought half of PeterGuthrie's, all CgSource, some CG-Skies (from creators of cg-textures) and even 4 dvds of DutchSkies (excellent, used in hollywood production, but not so good for pure IBL like the rest) only to end up using VraySun/Sky anyway :- ).

 

I've revisited the whole IBL with HDRi with Corona, chose 5-6 and started modifying them heavily. I will post about this soon. So you only really need few, and than it's a good investment and not expensive :- ).

[benjaminbogaert]

What can I say, at this point even small amounts are big ones hehe. Thanks for the info as always. Looking forward in seeing your thread Juraj.