I use Blender almost every day, as a 3D artist, from concept art, storyboarding to final 3D renders.
It was a tool when I started learning Animation, now it is a part of my life.
Renders can take a lot of time, depends on poly count, lighting, and textures. A good example will be a city scene and a camera is zooming in, this is very basic, but the scene contains large building which translates to dense geometry and lighting such a scene takes multiple points and area lights.
Textures are not heavy unless their 2K or above.
All this data takes a lot of time to process and sometimes, all we need is a preview to know, how well things are animated.
You could get a preview render in just a few steps. There are also various types of preview render, a good example is a Playblast.
To render a Playblast, you can follow this article.
Playblasts are to view animation, but for stills and image sequence, we need to tweak some render setup settings.
In the Sampling section, we have Sampling Presets, which contains “final” and “preview”.
By selecting the preview, we are choosing, six samples in the viewport render and 12 while doing the offline render.
The default settings provided by Blender is good for most scenes. You could change these settings to further adjust the render setup to your requirements.
If you have any questions, feel free to leave a comment below.