I use a ton of this film, including sometimes extreme push (like 4 2/3 stops). As you push more, you need to compensate exposure more, which is why three stops push is ISO 800 rather than ISO 1600 settings.
Generally a medium to low contrast transparency film, with medium saturation. Very favourable for skintones or blue sky in images. As you push there is little change in contrast, though extreme pushes (beyond 3 2/3 stops) result in bluer images.
I thought I had posted some information about extreme push settings suggestions here on APUG. It might have been last year. You do need to confirm with your lab how well this work. I would suggest a good push test as ordering a 3 stop push on two rolls; though shoot one at ISO 800, and the other at ISO 1000. After processing, decide which result you prefer.
Ciao!
Gordon Moat
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