Apple ProRes is currently a go-to standard. If you buy a brand new computer, it doesn't come installed. Here are some recommendations:
OSX: Apple's ProApps for QuickTime Codecs
- Visit this apple.com page to download their disk image
- If you don't have Final Cut, Motion, or Compressor, try using UNPKG, as noted by Ken E. on creativecow.net; for a step-by-step guide, see this YouTube walk-thru
- Move the contents to /Library/Quicktime/
We recommend the free app MPEG Streamclip to transcode your file. You can also use Apple Compressor, Adobe Media Encoder, Handbrake, and many other tools to achieve this.