Hi John
I shot mainly in 16:9, except for the slomo scenes (1728x584 @ 60fps).
As for the Intervalometer + Auto ETTR + FRSP technique, I reckon you're aware of the current limitations: the slowest shutter speed is 16" and the fastest 1/15. With this in mind, you will need an ND filter for sure if you want to capture day to night or night to day transitions.
I have used a variable ND filter, but didn't change the intensity during the exposure. Had bad experiences in the past doing so, with weird colour inconsistencies, which are hard to smooth out in post, plus if you dial the filter in the wrong direction, game over.
I set the interval to 20", my aperture to about f11, turned on Expo Override (this is essential), and then in the Auto ETTR menu, there's a very important setting you have to experiment with - Highlight Ignore. If you leave it at 0%, the camera will expose for the brightest parts of the image (say street lamps), which is not necessarily what you want.
During my field tests I found that 0.3% would work well, but when I got to Santorini, I had to adjust this because houses are whitewashed, and that tripped the exposure. I would advise against going over 1%, or else you may run into blown out skies, which you may not be able to pull back in post.
The above settings worked for me if I were to shoot from, say, 7pm to 10 am on a late spring day with a moderate amount of clouds. After 10am-ish, the sky would start getting overexposed. This is because, AFAIK, it’s not possible to change the aperture during the exposure. I’m currently looking into a lens with a manual aperture ring. They are relatively inexpensive and should, in theory, make it possible to shoot from sunrise to sunrise.
And, by the way, do not forget to revert the above settings if you’re shooting video after a timelapse
Then brace yourself for a mammoth post-production job, as you will have to compensate the exposure changes manually.
My best advice would be to experiment a lot before going on location. That really saved the day and prevented me from making rookie mistakes when it mattered the most.
I have read a lot of moaning about FRSP, because it doesn’t do this and that, but trust me, this is a truly game-changing technology for timelapsing, and I only have words of sympathy and deep appreciation for those who’ve surely burnt many eyelashes to make this work.
Take care and happy shooting!
Filipe
