[Joseph Livesey]

Thanks so much for your reply!

Yes, that’s right, the “optimal” ISO is also 850 for the C100, although I have seen plenty of people posting that they like to use higher ISOs (although nothing as high as 6000) because of the textured effect it can produce in certain situations.

I’m interested in more about your objection to using a gray card to judge “correct” exposure. I’ve found that technique quite beguiling as before I learnt it I was finding my footage with the C100 coming out of the camera unpredictable–sometimes looking great, but sometimes underexposed.

Still asserting that, using the gray card to expose with the wave form monitor, the high ISO with the ND filter brought detail in the highlights out that exposing in the same way but without the ND filter and the lower ISO did not.

And thanks for your pointers about shutter speed!

All best,
Joseph