Just like when working with any piece of software, you will be importing and exporting files of different formats. The VFX industry has its share of file formats that you must get used to using and learn the pros and cons of each.
First thing to note – in the VFX industry, video formats are not used. Although the industry deals with moving picture, video formats are not used because when rendering a 10 second clip at 24fps and each frame takes 10 minutes to render, there is a lot that can and will go wrong. If you’re exporting to a video format and encounter a problem such as a software crash or even if just one frame gets corrupted, you will lose everything. Instead, you should be exporting to an image sequence. If one frame is corrupted, you can easily delete it and re render that frame, or continue from where you left off in the event of a total crash.
Here are some file formats that you should be using.
OpenEXR (.exr) This file format is often used because it is capable of HDR, but is also capable of storing 1023 channels – The main benefit being that you do not need to create a separate image file for specularity, reflections, ambient occlusion etc and can instead keep them all as one file with surprising efficiency. It is also lossless – Even if you repeatedly export the file in this format, unlike a Jpeg, you will maintain the original quality.
Targa (.tga) Although it doesn’t work with HDR, it is a lossless file format capable of RGB colour channels, or RGBA depending on what bitdepth you are using.
Tagged Image File Format (.tiff) Sort of like a mixture of .exr and .tga, it has HDR capabilities like the exr, and can also be exported with lossless compression.
Portable Network Graphics (.png) Like previous formats, it is capable of lossless image compression as well as an alpha channel which makes it a decent basic format for use in VFX.
Here are a few you should avoid.
Joint Photographic Experts Group (.jpeg) This file format does not have the ability to be lossless, so every time one is saved, it loses some quality.
Graphics Interchange Format (.gif) Although it’s capable of alpha, is small, and even has lossless support to an extent, it does not support a very big colour range which simply won’t do for VFX.