I have just bought a year's subscription. I hope this isn't a mistake. The rendering of my 4k 60fps iphone video has been downgraded to a blurry rubbish clip. If this is what rush can do then I would prefer to cancel.
Sorry to hear that. Have you tried another preset for exporting? Could you share a screenshot of the video?
Rush actually does a great job with rendering 4K (I do it regularly for my church media)! The key is making the right selections in the Share settings:
You can use the automatic presets in the first dropdown, or fine tune your settings for Resolution (2160p 4K Ultra HD), Frame Rate, Audio Channels, and Quality.
* Just keep in mind that the higher the quality (res, fr, audio, and quality), as well as the more content you have and longer your video is, the longer it will take to render and more disk space it will need to render, so keep that in mind when planning your project (i.e., don't wait til the last minute to export your video - the earlier you can start, the better! I usually export 2 days before a due date to allow time for low bandwidth, corrections, etc.)
Hope this helps!