AWS Thinkbox Discussion Forums

no alpha channel in tiffs

Hi!



I have a problem when rendering in tiff format in Max8+Vray. There is no alpha channel in tiffs although I’ve set alpha checkbox in render output->setup window. So I have to render separate alpha channel through render elements. It’s ok when I have to render 1-5 frames, but when it comes to 20+ frames it becomes hard to add all these separate channels to tiff images with photoshop.



Thanks.

Hi Sergo,



I just tested this out and the alpha channel was saved with the tif

image (I tested with a 16-bit Color tif with the Store Alpha Channel

option checked in the output setup). I’m running the latest version of

Deadline (2.7.29178), along with 3dsmax 8 and Vray 1.5 RC4. If you want,

you can send us a very simple test scene that reproduces the results

(some geometry, a light, and a camera), and we can try to reproduce the

problem here.



Cheers,

Thank you for reply, Ryan!



I’ve tested simple scenes and it was ok, tiffs have alpha channel but when I’ve tried more complex scene alpha channel disappeared. I’ll send you a scene on monday.

I’m using latest version of Deadline too.

Hi, Ryan!



Here’s my test scene. I’m using latest Deadline, and I’m submitting jobs to Deadline through deadline’s maxscript “Submit to Deadline 2.7”.

I’ve tested this scene many times but couldn’t fix the reason why this scene looses alpha channel. Simple scene, for exemple plane and box on it works very well.

One thing that I’ve discovered is “Use Map” checkbox in environment dialog box. Then it is on, and map slot contains tiff bitmap resulting tiff file doesn’t contain alpha channel. But if map is jpg texture, or if there’s no map at all resulting tiff image contains alpha channel and everything is ok.

I’m not 100% sure of that behavior in other scenes, but it’s really rare situation in which I’m getting correct tiff files.

And one more thing: apart from alpha channels tiff file loose depth information - if I’ve set depth to 16 bit, I’m getting 8-bit tiffs without alpha channel. But, again, not every time but almost every time.



Thank you!

Hi Sergo,



Thanks for the scene. I first rendered the scene locally in 3dsmax, and

as expected, the alpha channel was saved with the image. I then rendered

through Deadline as I was able to reproduce this problem. So after

trying out a couple of things without success, I tried rendering the

same scene using 3dsmaxcmd.exe (3dsmax’s command line renderer). I

didn’t specify any parameters other than the “-continueOnError” flag,

which was needed to prevent a missing dll error (ColorCorrect.dlm).

Surprisingly, I got the exact same result as when I rendered through

Deadline (no alpha channel and lost depth information).



Because 3dsmax’s own command line renderer has the same problem, my

initial guess was that this is either a 3dsmax or a VRay issue. I then

switched over to scanline and tried the same test, and this time the

alpha channel was saved by both Deadline and 3dsmaxcmd. So it looks like

this might be a VRay specific problem.



Cheers,

Hi Ryan!



Thank you very much! It is really vray+deadline+tiff problem. I’ve tested my scenes with TGA, EXR formats, they all rendered without any problem, so I’ve decided to switch from the TIFF to EXR. It much more robust format, it’s float point, and finally it doesn’t loose alpha channel :slight_smile:

Privacy | Site terms | Cookie preferences