You always lose quality when reencoding (to a none lossless format) and during deinterlacing.
Hybrid and tons of other tools allow to deinterlace 25fps interlaced video to 50fps progressive video by a process called 'bobbing' or 'bob'-deinterlacing.
Bobbing takes each of the interleaved fields (top/bottom) and interpolates each of those to a full frame.
Unlike same frame rate deinterlacing, bobbing (double frame rate deinterlacing) does preserve all the motion data from the input interlaced source, so the bobbed source has potentially smoother camera pans than the otherwise deinterlaced content, but it won't create smoother motion than the interlaced the interlaced source.
Usually the only real way trying to get smoother pans it to create additional interpolated frames and convert to a higher frame rate.
QTGMC is currently the 'best' deinterlaced I know of.
You can create bob deinterlaced output with it and you can create same frame rate output with it.
Cu Selur
Ps.: you probably also need to replace the libmvtools.dll (see:
https://forum.selur.net/Thread-HELP-erro...ing-module), since the current version which comes with Hybrid might be broken.
PPs.: to get some basic understanding of deinterlacing
http://www.100fps.com/ is a good place to start.