Hi guys,

I'm having some problems using htoa in houdini.

For some reason I am not able to render arnold in the render view.
But when I press the render node my lefthand side of the screen (inside my viewport) arnold will render succesfully to mplay.. but when I am looking through the camera and press the same button Arnold will not render anymore.

This is the error I receive:

00:00:00 319MB ERROR | Unsupported camera projection: None
00:00:00 24MB | Received: log_verbosity: 7942
00:00:00 24MB | Received: log_console_enable: 1
00:00:00 35MB ERROR | there is no camera!

I found a solution:
Delete the cam.py node in the arnold scripts/obj folder..

C:\solidangle\htoa\htoa-1.6.1_r1459_houdini-14.0.395\scripts\obj

Then add the attributes manually by using the “add arnold property node” and everything should work fine now.. im now asking arnold developer why this is the case.

Glad you got out of that corner.

Can you tell me how's Arnold compared to Mantra when it comes to the speed of rendering the same scene with a visually similar amount of noise? Basically, which is faster in your experience is what I'm asking.

This is actually my first time using Arnold in Houdini!

At school we have many Arnold nodes at our renderfarm, and I just found out htoa use the same license as mtoa so I just installed htoa.

I really like arnold! It is extremely fast, GI is always turned on so you instantly have realistic results. Compared to Mantra the workflow feels the same actually, the shaders have the same settings so its easy to switch to Arnold.

You can try Arnold for free by the way!
On their page you can download the plugin, if you dont have a license you will get some watermarks but that should be ok for trying out..

I haven't tested them in volume rendering but in the hard surface indirect light setup tests I did Arnold was faster than mantra. That is of course without caching GI and pure PBR.