rscheffler Offline Upload & Sell: Off
|
rscheffler wrote:
@docusync@@ What about going past 5 stops and staying neutral? For example I'm thinking of video if shooting in a log mode where the 'ideal' ISO is 800. In full sun ~1/60 shutter and wanting to shoot wider apertures, you're going to need more than 5 stops. I think some stack a fixed ND with VND...
docusync wrote:
There are some options like 2-9 or 3-9, but I never tried those, sorry. Except for the Canon EF-RF VND adapter but I cannot recommend that one because it's extremely blue and uncorrectable at 9 stops.
I think there is nothing wrong using an ND + VND, if they are really neutral. You can stack a couple of VNDs as well, but consider that their external diameter is always one size bigger. I.e. you need 77 and 82, or 72 and 77. I did it once with a couple of B+Ws. The result was barely correctable though
Regarding Log and ISO - here's a great article about exposure: https://www.xdcam-user.com/2018/08/noise-iso-gain-s-log2-v-s-log3-and-exposure/?amp=1
TL;DR for normal looking graded footage you need to overexpose by 1.3-1.6 stops (SLog3 or CLog3). Yes, you will protect your highlights if you don't overexpose but your midtones are going to be noisy when you lift them to the appropriate level.
...Show more →
Thanks for the link and info. My understanding is VNDs are polarizers and stacking a couple just leads to more problems. The appeal of shooting log is that the tone curve applied to the footage lifts the shadows so they don't crush like they do with the standard non-log in-camera color styles/profiles. Apparently my camera also switches to internal 10-bit log recording vs. 8-bit with the standard profiles, which provides a little more flexibility in post. From the reading I've done, because of the gain applied at 'base' log ISO (800) it's better to ETTR, as you suggested. One source suggested just putting the histogram peak to the right without clipping. I have to play around with it more to determine if there is really any gain to shooting log at 800 vs. lower ISOs. IIRC (I don't have the camera with me right now), when ISOs are below 800 when in log, the histograms usable range is compressed on the right (highlight) side to imply it's capturing a narrower tonal range...
|