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digitalimagery
07-12-2011, 09:31 AM
I've just finished rendering a logo animation and I'm getting some really unacceptable anti aliasing around my text (it's sub text so it's small but it should still be anti aliased).

I've set Classic Camera Anti Aliasing to Classic, Enhanced Extreme, the Output Alpha Format to Unpremultiply Alpha which "should" mean the RGB does overshoot the Alpha. Finally the Camerais set to an anti aliasing level of 6 which should be fine for video. Am I missing an option somewhere?

I used to work with Electric Image and it would render the RGB channel to overshoot the alpha channel by several pixels leaving it poorly aliased but the mattes were flawless thereby cutting the rgb with razor sharp edges. Is there any option for that in LW?

I've attached a JPG which shows the issue. This will be displayed on a large screen before a presentation which will further enhance the problem.

Any help would be appreciated.
Thanks.
Randy

digitalimagery
07-12-2011, 09:34 AM
The missing attachment

archijam
07-12-2011, 09:38 AM
Have you tried doubling the res, halving the aa ? (Then resizing after render).

This is not a complete answer, but an emergency one .. (can't remember the last time i used the classic camera).

What format are you rendering to?

robyht
07-12-2011, 10:16 AM
Hi have you tried using perspective camera with reconstruction filters such as mitchell sharp, lanczos etc

digitalimagery
07-12-2011, 11:00 AM
Thanks as mentioned to robyht, I'm new to Lightwave and haven't experimented with doubling but that's an interesting workaround. I generally prefer to render to Quicktime but when I try I don't get alpha channels and the options button isn't bringing up the ability to render RGB+ Straight (Not Premultiplied) so I output to 32 bit Targa

digitalimagery
07-12-2011, 11:14 AM
...robyht. Problem solved wasn't sure what those options were for but a serious improvement. Thanks!
Randy

PS. I love this community

Sensei
07-12-2011, 11:34 AM
The first rule in LW, is not to render to animation file directly.

digitalimagery
07-12-2011, 11:44 AM
Sensai,
What do you mean don't render to animation file directly? Now I'm confused again. You mean render to numeric format in case of a crash or some unexpected problem during rendering?

Most of the work I do is short logo animations for corporate and broadcast clients. The animations are usually between 5 and 15 secs so re rendering usually isn't a big deal. hen time is tight I render to numeric formats in case I need to re-render a range for a fix or change.

RC

robyht
07-12-2011, 01:14 PM
Hi Digitalimagery
No problem with the fix, I had exactly the same issue with a tv ad a few years ago, reconstruction filters saved the day. In fact I now always use Mitchell first, then move to the others to see if they work, but I find Gaussian too soft and Lanczos too sharp for broadcast tv, all depends on what the use and content is.

Also, I agree 100% with Sensei. We always render out frames/fields from Lightwave, we never make QTs directly in it. we then use Fusion (or AE or any other compositor) to compile the frames, colour correct, generally mess with, and when we are happy with the look we render out from Fusion an uncompressed avi. Then we go to Super (it's free and fab) to make a nice and compressed QT.

Generally though, our clients either want an uncompressed avi, or uncompressed frames (tiff,png,etc.) for final delivery, so Super is not used for anything other than client approval, tests, web stuff, etc.

Cheers

Rob

digitalimagery
07-12-2011, 02:06 PM
Thanks every one for the feedback. This worked well. The render is almost done and I have two more in the wings so the fast responses saved the day.

Randy (a.k.a. digitalimagery)

Matt
07-12-2011, 02:18 PM
I've just finished rendering a logo animation and I'm getting some really unacceptable anti aliasing around my text (it's sub text so it's small but it should still be anti aliased).

I've set Classic Camera Anti Aliasing to Classic, Enhanced Extreme, the Output Alpha Format to Unpremultiply Alpha which "should" mean the RGB does overshoot the Alpha. Finally the Camerais set to an anti aliasing level of 6 which should be fine for video. Am I missing an option somewhere?

I used to work with Electric Image and it would render the RGB channel to overshoot the alpha channel by several pixels leaving it poorly aliased but the mattes were flawless thereby cutting the rgb with razor sharp edges. Is there any option for that in LW?

I've attached a JPG which shows the issue. This will be displayed on a large screen before a presentation which will further enhance the problem.

Any help would be appreciated.
Thanks.
Randy

Two things for future.

1) Adaptive Sampling gets the best results, but can be slower. 0.03 Is a good general purpose setting.

2) Sometimes you may need to turn on Limit Dynamic Range in the Render Globals tab.