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Hello community,

i am having trouble using the MatID-channel for compositing, because the AA is different in Alpha vs. MaterialID.
Usually i`m assigning pure colors (RED,GREEN,BLUE) to get a multicolored Mask-channel, but due to the difference in AA with these thin lines - it doesn`t work properly!
In my opinion AA should be identical in all channels...is it a bug?

best regards
munch

wild guess - - perhaps the matIDs need to be gamma'ed up (2.2) before use.

The gamma will change the mid-point of the luminance curve and might be the difference between the images.

thanks for the hint renbry - but this doesn`t work

You might want to try different settings for the Sharpness (under Tone Mapping) -- it may be that the one output is being filtered and the other not.

Best,
Jason.

thanks half life,

but no success!

...looks like sharpness has no effect on the MatID-channel...
but i can make the Alpha look more jaggy this is not what i want...i want the MatID to look like the smooth Alpha...

hello next limit team,
please tell me why they doesn`t match!

is it a known limitation?

best regards
munch

You have to be more like Ernesto to receive any answer

I have noted the same, but I thought that it was due to the file format.
The default file setting for Alpha channel is PNG16 but the default setting for material id or object id is PNG8.
I haven´t tried changing all the channels to PNG16 yet, but I would expect it to solve this issue.

Ernesto

zdeno wrote:You have to be more like Ernesto to receive any answer

Ernesto wrote:I have noted the same, but I thought that it was due to the file format.
The default file setting for Alpha channel is PNG16 but the default setting for material id or object id is PNG8.
I haven´t tried changing all the channels to PNG16 yet, but I would expect it to solve this issue.

Ernesto

I wondered the same but seeing as your screen is 8bit you should see no difference, Mat ID must be calculated differently.
I too would love to know why this occurs... In fact there is still so much I would love to know about how antialiasing works in Maxwell

no matter what depth i`m using 8 or 16bit...the AA differs...this makes the usage of MatId/ObjID for postproduction pretty useless
the only workaround to get a proper mask is to render all objects needed as a seperate alpha-pass...

hello next-limit team,

if it is no limitation, would you please tell me what i did wrong?
...and how to get useful mat/obj-id that doesn`t differ in AA?!
...or what is the intention of these channels?

thank you

4 weeks since the first post and approx 500 views, but no answer from NL!

I think no answer is an answer...

You have to insult few people to get something ... it is checked many times.

shy and modest are not supposed to get answers fast.