AndreeMarkefors wrote:If you shoot UHD or higher resolution footage and want an HD product, you can do all the work in a HD timeline, but when done, set the timeline back to UHD (or the resolution of your native footage) and then export to HD from that.
I don't think I've personally compared:
HD clip --> HD timeline --> HD product vs HD clip --> UHD timeline --> HD product
I'm not implying it will be better, but it might also not take a great hit. Sometimes you might have mixed footage and might need to scale up to UHD to match the rest of the content before export.
I've just tested with a DCI 4K clip in a DCI 2K timeline exported at 2K versus a 4K timeline exported at 2K, as tiff sequences. The results were mathematically identical, so if your target is HD then unless you are doing something in the grade that benefits from a 4K source then there's no need to go back to a UHD timeline for processing. The difference comes if your target is a higher resolution than the timeline, so if it's a UHD target then an HD timeline will be detrimental to the final output.
I also tested having sizing set to crop with a 50% zoom in the timeline, versus scale to fit. Again, the results were mathematically identical, though I'd go with scale to fit as it's less messy and there won't be any risk of accidentally pasting or removing a zoom you don't want to, especially if you have clips of different resolutions. If one has been zoomed in 20% and you want to paste this to a clip that has already been zoomed out 50%, you can't as 120% from 50 will be far too much; and making it 70% won't be right either (in this case the correct zoom would be 60%, but I'm sure you could do without having to do maths while editing especially if it's a less convenient zoom increase).