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Hi,

When I try to animate light sliders in the MXI Mixer node something strange keep happening.
Here is a file (also sent to tech support): https://dl.dropbox.com/u/1059954/Maxwel ... ellBug.zip

I rendered with four lights, and the MXI mixer registers all of them when pressing "set channels". But then it randomly jumps between three lights and four lights in the MXI mixer node.
I also get image artifacts when adding a new nuke node under an animated mxi mixer node. See example in file.

I have the latest plugins.

Also looking for another and more stable route. Is it correct that shuffling out the lightpasses and merging them with "plus" gives the correct result? How would you change the light intensity? Could you use "multiply" under the grade node?

Hoping for some tips

Best regards,
Tor M

I can reproduce the problem. I hope I can give you news next week

Also looking for another and more stable route. Is it correct that shuffling out the lightpasses and merging them with "plus" gives the correct result? How would you change the light intensity? Could you use "multiply" under the grade node?

Yes, I think you can emulate the MxiMixer node using Grade(multiply)/Multiply for light intensities, and Plus for light mixing.

Furthermore, if you attach a ViewMetaData node to the MXI, you can see some useful info in case you want to automatize a Grade/Plus set of nodes using Python. The "Color Adjustments" tool uses that info so you can take a look at the "mxihue" function in the "maxwell_utilities.py" file.

Thank you for looking into it.

I even get the artifacts when I shuffle out the lightpasses, so the alternative route is also a bit hit & miss.
I guess your plate is full, but there is always a deadline and the MXI mixer is crucial for the project.

Dont want to stress you, but a solution sooner than later would be highly appreciated.

Best regards,
Tor M

Did you try using EXRs instead of MXIs?

You can use the MxiMixer node with EXRs generated by Maxwell (using the "Multilight: intensity + composite" option). If you don't have the EXRs, you can generate them using the tool "File->MXI batsh processing..." on maxwell render.

Ah, nice tips. Will try that!

Thank you

Hm, same problem occur when using MXI mixer on exr´s.
It seems there is something happening with how mxi mixer interprets the light intensity number.
When I import exr´s, add Mxi Mixer and presses set channel. I´ll get numbers like:
Fill_1: 5950
Fill_2: 83
Key: 163

These numbers give a "normal exposed" image, but suddenly the image is "super over-exposed".
If i then change the numbers to something like:
Fill_1: 1.22
Fill_2: 1.38
Key: 0.425

The image is "normal exposed" again.

Sometimes the transform node can make this happen, sometimes the card3d node and sometimes the grade node. Just seems like a random event.

So, I guess the problem lies in the MXI mixer node and how it interprets intensity numbers.

What do you think?

Best regards,
Tor M

MxiMixer saves the light intensities of the MXI to the .nk file. It seems there is a problem when the node is animated and it is reset when the animation cicle completes after a "play" click. It makes the slider's ranges being set to 0-1, and the number of light controls showed becomes 3 (regardless the "Total Lights" knob value is right (4)). That can cause the light intensities (10000, 250, 300, 250 in your mxi) are reset internally in the mximixer node to 1, so the lights will be 10000, 250, 300 and 250 times over-exposed in your case!

I'll try to send you a new version of the plug-in today.

PD: that not solves the artifacts issue, but I see in times the problem can be corrupt data in the Nuke cache, so a "Render->clear buffers" and a "Render->clear disk cache" can solve the problem. It worked for me sometimes.

Thank you for looking into it.

Regards,
Tor M

New beta version trying to fix your problem:

http://download1.nextlimit.com/temp_upl ... .4_win.exe
http://download1.nextlimit.com/temp_upl ... osx.tar.gz
http://download1.nextlimit.com/temp_upl ... nux.tar.gz

Thank you, I´ll use it and let you hear how it works.

Regards,
Tor M

I have tested the update over several days now, and it seems to work well.
If I hook up mxi mask in my node flow, nuke crashes. But that is not really a big problem for me, just use primatte to isolate out the different object id's.
Thank you for fast and good help!

Best regards,
Tor M

I am sorry to tell you that the problem still occur. Strange.
It worked several days, and then the "over-exposed" image is back.

Any new medicine?

Regards,
Tor Martin

Try that new beta.

http://download1.nextlimit.com/temp_upl ... .5_win.exe
http://download1.nextlimit.com/temp_upl ... osx.tar.gz
http://download1.nextlimit.com/temp_upl ... nux.tar.gz

Now I take into account some unexpected things that nuke do when a slider changes. I hope that finally solves the problem!

Thanks. Changed to the new plugins in the middle of a project. All sliders went crazy
But I got back to where I was but tweaking the sliders with a small amount.

I will test this out, thanks again!

Regards,
Tor Martin