Vray AVI output doesn't match render resolution

[projectveeti]

So I just finished up a 70 animation render on 3DS with Vray. I had my resolution set to 2k (2560x1440) and when I did single frame test exports the resolution was correct. However, after the 70 hour render finished and it exported the AVI file the resolution was cut down to (720x480). Does anyone have any idea what would cause this?

[CiroCardoso3v · Accepted solution]

Not sure why that happened. But if you are exporting an animation don't use an video file. Always use EXR files and in a situation like this you could save the animation by scaling the files from 720 to 2560.

[projectveeti]

Just out of curiosity, why is it a bad idea to save as a video format when rendering an animation? Also, what are the benefits to using the EXR format?

[CiroCardoso3v]

A couple:

First, if you are rendering an animation and the file crashes, exporting as an image sequence, means you can restart from frame 60 for example, instead of having to re render everything again. 

Rendering an image sequence also means you can use something like After Effects, Nuke or Fusion, to improve your shot. Exporting a video means that you are already compressing the file and even if you go to one of those applications to adjust something in your video, isn't the same flexibility or quality.

EXR is the best file format to render sequences of images, because is a 32bit file, meaning that you can easily adjust things like Exposure, Contrast, without clipping the blacks or whites. Is also a file that is optimize for Nuke and other applications.

Also, rendering a sequence of images, means you can also export render passes, like Material ID, Specular, etc, that can be used to again enhance and adjust your shot.

Of course, that if you are just doing a quick draft, or a playblast, then using a video format is perfectly fine.

[projectveeti]

Great explanation! I'll give it another try, this time using EXR image sequences instead. Thanks!