Have Casio fc150 but....

I am having trouble with video transfer quality. I know that high speed at 1000fps, 420fps etc sacrifices somewhat the video but when i transfer/download to my Macpro -newest 2015- the video is blurry and looks worse than 3rd gen copies of old tape days....
Do Ii have to set up my Macpro's display settings or preferences? The video playback on the camera's dipay is sharp and nice. Any suggestions? Planning to upgrade to Sony rx10 or canon soon but want to address this problem. 
Thanks even if there is no immediate answers/replies!
 
Thank you for the reply! Yes, I was using 420fps but found that my "normal" stuff was not great or HD quality as it is on my camera's display. But I am not really near being an expert. I am looking into a Sony RX10 II that shoots 900fps and is suppose to be far greater than the Casio range of offerings in high speed performance. Hopefully, the manual with it will help me on the way of having video on par with the rest of you guys and gals on the net....
Thanks again for the response!
Sincerely/Mahalo,
OldFalc