[itsallgoode9]

I'm starting to run into a pretty annoying isue lately with the rendering of high res alpha maps. Basically, I'm rendering some alphas at 4k and they are just solid white and black, no transparencies. The problem is that it takes FOREVER to get crisp edges on the alpha renders. I am rendering bottle labels and need to mask out some lettering so I can change the colors in Photoshop in post. Usually the super precise accuracy isn't important, but in this case, if it is not 100% accurate I get some white "halos" around the letters in photoshop when adjusting the colors and values.

Is there any way to make alpha rendering quicker?

I'm using an Intel i7 920 with 12 gigs of ram, so computer speed is not the issue.

here's an image of my render after about a 1/2 hr. At this rate it's going to take 3-4 hrs at least to get a precise alpha

[Mihai]

It's rendering the main render also at the same time? It will be slower of course in that case, if you just need the alpha, uncheck the main render channel.

[itsallgoode9]

thanks for the reply... I am doing only an alpha render and have the diffuse box unchecked. I ended had to let this render for 2.5 hrs and it still wasn't perfect, it was just "good enough" that i'll be able to fix it up in photoshop.

It's kindof annoying that maxwell likes to treat these alpha renders exactlly like a real render....it seems like there's no reason that an alpha should take more than like 5 minutes to render argh.

[jc4d]

I feel your pain, that´s why I render my alphas in my main modeling software (biased way )

Cheers
JC

[itsallgoode9]

yeah, unfortunatly, I like to use standalone for all of my rendering, so I don't have that option, argh!

One thing I have been doing though is sometimes rendering inverted alpha maps. If the majority of an alpha is white, i'll invert the map in the material so that it makes the majority of the renered alpha black which then makes less white area for maxwell to fill in. Once it's done, i just invert it again in photoshop. This helps speed some things up alot, depending on the render.

[itsallgoode9]

Ok, I just had a stroke of inspiration that I will test out tonight and post results and a tutorial. I have a method should make rendering large opaque alpha masks, such as my example, take about 10 minutes instead of 2hrs!! hopefully it works