Since when have you seen an everyday consumer with their lousy 360p cameras doing chroma keying, color correction and stabilization on FCP X?
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You might have an external SSD, but how huge is it, 64? 128? SSDs are expensive. And usually even overpriced.
256GB...which is plenty. The current commercial I am working on off of it is using 16GB.
Pro users who uses pro apps such as Logic Pro and Final Cut Studio needs scratch disks. And depending on their project, it could go up to 50 terabytes. SSD just simply cannot fit in their budget. Besides, I used a HDD before, it wasn't that horrible when it comes to playing 1080p.
Not when working on a project that has 56 CG layers that all need to be read at once.