I used the original Ashley Library 04 (1080p) 26 FPS as a source video.
So the way I see it, I have 2 options:
- Leave it as is and work with defaults, which in my opinion provide satisfactory results.
- Downgrade to a lower version, which uses older AI models, but seems to give users more configurability.
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We could have a separate thread for encoding/interpolation discussion as these can go long

Flowframes 1.36 is the latest Free version, 1.40 latest Patreon version.
Encode quality options are based on either bitrate input or CRF value.
The slow/fast preset does not control bitrates but defines which encoding algorithms to use:
Preset is a predefined set of encode settings where slower is better till a point post which is not practical.
If using slow preset, encoder will use better compression algorithm resulting in slighty lower file sizes.
If using slow preset, encoder will use better motion-detection algorithm resulting in better quality encode.
Standard preference for preset: Slow
For quality control, you can try decreasing the CRF value in encoding settings by 1 and find the value that suits your quality preference.
Standard preference for CRF: 16-22
Note: Above information is for clarification on ongoing discussion to help with individual choices; personally prefer original rendered video from artist for archiving.